September 6, 2022 • 51 mins
You might not think your car’s odometer is that exciting, but it’s actually the modern incarnation of an ancient invention with roots in China and the Greco-Roman world. Join Robert and Joe as they discuss the invention of the hodómetron and the li-recording drum carriage in this invention-themed episode of Stuff to Blow Your Mind.
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Speaker 1 (00:03):
Welcome to Stuff to Blow Your Mind production of My
Heart Radio. Hey you welcome to Stuff to Blow Your Mind.
My name is Robert Lamb and I'm Joe McCormick. Today
Unstuffed to Blow your Mind, we have another invention themed
episode for you. We're gonna be talking about something that
(00:24):
might initially seem frightfully dull or at least very commonplace,
and that is the odometer. I mentioned this to Rachel
earlier and she was like, oh, yes, the device that
measures odors. Yes or odo's. If you were to read
the word wrong, you might think it says autometer, um,
but it's yes, the odometer. So everyone other you probably
(00:45):
know this device best is the little counter in your vehicle,
the records how far you've driven. And I think we
tend to think of this invention mostly as a self
centered device. It tells us how far we've driven on
our trip, how many miles or kilometers we've racked up
on our vehicle. But you know, there's another way of
looking at the odometer, and this, certainly this is something
(01:07):
that plays into and into the history of the invention
and also our attempts to understand its place in the
ancient world. Is that an odometer can also be a
method of determining distances on given routes. It's something that
turns a vehicle into a tool from measurement, right, So
it's it gives you information that would be useful to
(01:30):
other people, because I mean, in the ancient world, you
don't have Google Maps or anything. You might know that
there are two cities, and you might know that you
get from one of them to the other by following
the road to the west, but you might not know
how long it's going to take you to get from
one to the other. So it would be very useful
if you actually had some standard distance measurements that would
(01:50):
allow you to estimate the length of the journey and
to know how much you need to pack for the
journey and so forth. Yeah, we've talked before about the
some of the the important things that make up an
empire and make an empire or a kingdom function, and
there are things like standardized measurements, of course, and standardized currency.
But another thing that would be useful is indeed, like
(02:13):
you say, to know how long it takes to get
from one place to another, what is the distance from
one place to another, from border to border from port
to capital, from frontier to ford and sofa forth. And
this is the kind of thing that would of course
be important for warfare, but also for trade and just
general management of a given territory. So on one hand,
(02:35):
you can imagine this situation, and you can and you
can think about what an odometer is, and knowing that
an odometer has uh some of its history in the
ancient world, you might think, well, this is the this
is the route we take to get to the invention.
This is the necessity, uh that is the mother of
this invention. But this doesn't necessarily seem to be the case,
as we'll discuss, as we look at at its history
(02:57):
both in the east and in the west. Now, I
think it's worth thinking at least just a little bit
about maps and cartography here, because it's easy for for
the mind to go there, like I need to know
the exact distance between X and Y because I want
an accurate map, right, Uh. To kind of go hand
in hand when we think about maps today, Like even
if I'm looking through a Dungeons and Dragons book, I
(03:19):
have a map of some sort of fantastic region, and
then I have a little indicator to tell me exactly
how how many miles and inches or something to that effect. Oh,
once you get into D and D, though, I feel
like it's often very loosey goosey about travel distances. Oh yeah,
and um and as a when I am dungeon mastering,
I I am also I hate it when there's like
(03:40):
a really specific question about distances, like, well, is it
is it one mile or two mile? It's like, I
don't know, it's just it's however long it takes to
get there. But any well, my experiences, you want to
you want to take a queue from the d M
basically like, is this a journey where things will happen
on the journey or a journey where we will just
magically arrive at the destination? Yes, sometimes the magic is
(04:03):
in the journey, but sometimes it most definitely is not.
So thinking about this the situation about figuring out knowing
what the distances are between one place in the other,
and thinking about the role of maps in the ancient world.
I turned to one of my my favorite go to
text for a lot of this sort of thing, Brian
Fagan's The seventy Grade Inventions of the Ancient World, And
there's a there's several different chapters in there, the deal
(04:25):
with measures and maps. Uh and of Fagin and his
co authors point out, I think a few important things
about ancient maps that we might want to have in
our head as we proceed. So, first of all, they
point out, the Chinese maps of old were more about
landscape features. So the journey from X to Y is
more about the details of the landscape and the markers
(04:49):
that are passed on the way. Yeah, that makes sense,
navigating by landmarks. Yeah, and so the maps would reflect that.
Another thing they point out is that while local maps
in the ancient world we're one thing, as we're specialized maps,
broader maps of the world or region, we're not really
part of the overall ancient approach to maps. There were
(05:09):
no regular standards of map making, and there were no
general purpose maps. And uh, this is one quote from
the book I thought was rather telling quote between them rulers, generals, sailors,
and traders evidently all but ignored the practical assistance that
maps could afford them. That's surprising. Yeah, I mean hindsight
(05:31):
twenty but uh, yeah, it's interesting to look back and
think about what benefits this broader approach to maps general
purpose maps, etcetera. Could have afforded them, So I think
all that's worth keeping in mind as we proceed here.
None of this is to say peoples during these eras
were not concerned with precise distances, but the relationship with
(05:51):
exact maps wasn't quite the same as what we have
now now. Another way of thinking about what came before
is that there certainly were ways of measuring long distances
before the invention of the mechanical odometer. Though there is
some question about the relative accuracy of early mechanical methods
versus pre mechanical methods, and one case study here that
(06:14):
I think we should look at. It's very interesting puzzle
that emerges if you look at a geography chapter of
The Natural History by by our old friend Plenty of
the Elder. Here I'll be referring to the Bostock and
Riley translation for those not familiar. Plenty of the Elder
was a first century Roman military commander and author, and
(06:36):
the Natural History is an early attempt at creating a
sort of world encyclopedia. So Plenty covers everything from mining
and metallurgy to botany and zoology, cooking, politics. It's just
it's just a book of everything, and in book six
of the Natural History, Plenty sets out to describe, quote,
(06:57):
an account of countries, nations, sees to ounds, havens, mountains, rivers, distances,
and peoples who now exist or formerly existed. Very good
chapter heading there. One of the chapters within this volume,
chapter twenty one, is on the nations of India, as
known to Plenty at the time. Again, this is the
(07:17):
first century CE. So Plenty says that India is a
vast country with over a hundred kingdoms, dozens of rivers,
uncountable mountains, but he will undertake to describe some of
it by following the path of Alexander the Great, who
led a conquering army to India about four hundred years earlier.
(07:38):
So Plenty rights quote, however, that we may come to
a better understanding relative to the description of these regions.
We will follow the track of Alexander the Great. Diagonitis
and Biton, whose duty it was to ascertain the distances
and length of his expeditions, have written that from the
Caspian Gates to hecatom Pylon, the city of the Ptarthians,
(08:01):
the distance is the number of miles, which we have
already stated and he mentioned a number earlier, and then
he goes on and that from thence to Alexandria of
the ri I, which city was founded by the same king,
the distance is five hundred and seventy five miles, and
from thence to Prophesia, the city of the drag Ni,
one hundred and ninety nine miles. And from here he
(08:24):
just goes on and on, listing distances. It's this many
miles to the next city, and this many miles to
the next city. Uh. So he attributes all of these numbers,
all of these distances and miles that he comes up
with for this path leading into India to these two figures,
Diagnetis and Biton. Who were these guys well, they were
(08:46):
known as Bimatists, coming from the Greek word meaning step
or pace. I looked up Bimatists in the Oxford Handbook
of Classics, and the entry does identify them as the
the surveyors essentially of Alexander the Great Uh and names
a few other ones. In addition to the two already
(09:06):
mentioned Byton and Diagnetus. It also names uh Philonides of Crete,
who it says in a side note, was a celebrated
distance runner, and the entry also notes that the two
figures who worked for Alexander, Byton and Diagnetus, as well
as some others quote had literary aspirations. Their measurements of
(09:27):
key distances in the empire comprised an archive later controlled
by Seleucus. The first individual Bemetists published their observations in
monographs termed stath moy or Stages, which combined precise calculations
of distance with more exotic reports of the flora, fauna,
and customs of the empire. The latter tended to the outrageous,
(09:50):
but the measurements were of lasting value and provided Eratas
the Knees with the framework for his geography of Asia.
Aretas the Nees, you might recall, was an really figure,
a Greek philosopher who with pretty startling accuracy, calculated the
actual size of the sphere of the Earth. And he
(10:11):
did that just using knowledge of the distances between locations
of different latitudes and then the use of the angles
of sundials. Basically, yeah, So, how did the Bematists actually
measure distances in the time of Alexander the Great? Well,
I've seen some disagreement on this, some sources imply that
(10:33):
they simply counted paces, so you'd walk and count how
many steps you took, while others suggest that they used
some kind of mechanical device. One of the weird things
is that, as far as we can tell, most of
the distances recorded by bematists such as Biton and Diagnetis,
as well as others from the ancient world, are surprisingly accurate.
(10:56):
On this point, I want to quote a book I
was looking at by a American historian named Donald W. Ingalls.
The book is called Alexander the Great and the Logistics
of the Macedonian Army from the University of California Press
in nineteen seventy eight. And explaining a table in his
book of the bimatists different estimates of the distances between
(11:17):
cities on this route, ingles rights quote the overall accuracy
of the bimatists measurements should be apparent. The minor discrepancies
of distance parentheses only one point three percent from herat
to begrum, can be adequately explained by slight changes in
the tracks of roads during the last twenty three hundred years.
(11:38):
The accuracy of the measurements implies that the bimatists used
a sophisticated mechanical device for measuring distances, undoubtedly an odometer,
such as described by Heron of Alexandria. So there's a clue.
Uh Ingles here says, Look, the distance is given by
these these people who worked for Alexander the Great and
(11:59):
other immotists of the era. They're just too accurate. They're
too good to be the result of trying to count
your steps and estimate from that. They have to be
using some kind of machine that we don't know about,
and one good candidate is a machine like the one
described later by Heron of Alexandria. Now, this idea that
they may have simply been walking, on one hand, I
(12:22):
can't help but think of the Monty Python ministry of
silly walks and imagine like a specific, ridiculous but regular
date that they're using, and and if they were super
focused on their steps and counting their steps, maybe that
would explain why they're reports of flora and fauna are
so outrageous. They're like, well, I was it was. It
(12:43):
was three thousand, eight hundred and seventies six steps. And
to the left there may have been a dragon. I'm
not sure. I was just really focused on these steps
and getting the step count right. I mean, descriptions of
local flora, fauna, and people's of the world are notably
hilarious throughout all kinds of ancient texts, including Plenty himself.
(13:04):
He loves to talk about people who had like eyes
in their stomachs and stuff. Yeah. I keep hoping one
day I'll come across a passage in Plenty where he
mentions people who have crab clause. I haven't found that yet. Oh,
I have to have to look into that, I mean,
because you mentioned it's it's of course not just Plenty
in his writings and travelers that he's sourcing, and we
we've discussed similar things in Chinese traditions as well, So
(13:26):
there have to be some crab claude individuals out there somewhere.
But okay, sorry to Hero or Heron of Alexandria. Multiple
sources I found point to a device described by this
first century mathematician and inventor, sometimes known as Hero, sometimes
known as Iron, but he was from Alexandria, Alexandria, Egypt.
As you can tell by the name. A lot of
(13:48):
inventions are attributed to Hero, though some of the most
famous ones probably predated him, and he just described them
in lectures and writings, and then later that gets sort
of mistaken for him having actually invented the thing in
the first place. In the latter category. One example, in fact,
one of the most famous devices associated with Hero is
(14:10):
the Yala pile, which is a type of early steam
engine converting the power of steam into rotational energy. Basically
it works, but you've got a big cauldron this full
of water, and then you put a fire underneath it,
and then that cauldron is connected by pipes to a
sphere that can rotate around the pipes, and then the
(14:31):
sphere has two little exhaust nozzles that allow steam to
escape as the water boils and turns into steam and expands.
But the way the nozzles are oriented, they're oriented in
the same rotational direction, so as the as it gets
hotter and hotter and the cauldron and the steam pressure
builds up, it spins the sphere faster and faster. Yeah,
(14:54):
there are a lot of images of this, as I recall,
I remember seeing a cool woodcut of this, I think
at one point um but it has a look of
of a novelty of a device that's that's illustrating the
principle here, but but of course not putting it to
the sort of work that later UH steam engines would.
For sure. Yes, and though the e Allo pile is
(15:16):
often associated with UH, with Hero, I think this is
something that he very likely did not actually invent. It
was just something he described that already existed. UM. But
we have talked about other machines possibly invented by Hero
in previous episodes. One that I remember is the Hero
of alexandrias In is credited with inventing the first vending machine,
(15:39):
which strangely was also a piece of religious technology. It
was a machine designed to dole out limited portions of
sacred water within Egyptian temples when a devotee would insert
the right amount of coinage. So I think you'd put
a five drachma or five drama piece in through a
coin slot, and then that would operate a weighted lever
(16:01):
that would dispense a certain amount of holy water, and
then once a certain amount of water had gone out,
the machine would tip over and then it would close
the valve and stop dispensing. Though even in this case,
I read that it's actually possible Hero was simply describing
a device that had already been invented by two Cbs
of Alexandria in the third century BC. So, as with
(16:22):
a lot of ancient inventions, it's often hard to tell
if somebody actually invented something or if they're just talking
about something that already existed. Anyway, I found multiple references
to Hero either inventing or describing an odometer, as evidenced
by a passage he wrote in a minor work called
the Dioptera, which I wanted to find the full text for,
(16:44):
but if it has been translated into English, I was
unable to find it, so I don't know if that
even exists in English. But regarding this, this machine he
describes in the diopter again, the Hero is first century CE.
A couple of caveats. One is that he Hero was
definitely not the first known author to describe an odometer
in Greek. In the Greek and Latin Corpus, the Roman
(17:07):
engineer Vitruvius, who lived in the first century BC, so
century before Hero, also describes an odometer, uh, though in
a slightly different way. I'll get into the differences in
a minute. But even Vitruvius does not claim to have
invented the device out of whole cloth. And then there's
a second caveat which is that remember again Ingles making
(17:29):
the comment that Alexander the Great's bimatists must have had
a device like Heroes. The problem here is that hero
of Alexandria and Vitruvius both lived along after the conquest
of Alexander the Great. So if it's true as Ingles
suggests that these bimatists used a mechanical odometer similar to
the one described by these engineers and authors, they would
(17:52):
have been using some kind of earlier device similar to
Heroes or Vitruvious. Is not something that hero or Vitruvious
and vented. Now. An interesting source I found on on
these two device descriptions is a book called Technical Exprassis
in Greek and Roman Science and Literature, The Written Machine
(18:13):
between Alexandria and Rome. This is by an author named
Courtney Roby from Cambridge University Press. Courtney Roby is a
professor of classics at Cornell and in this book, this
is in the context of explaining patterns of composition in
Greek and Roman technical books, how in different times and
(18:33):
cultures there were different standards and uses for technical explanation
of machinery. Hero and Vitruvius both wrote books describing odometers.
I mentioned Heroes, but the the earlier mentioned by Vitruvius
comes in a book called on Architecture, and according to Roby,
Vitruvius himself acknowledges that the odometer is quote part of
(18:56):
a technological tradition handed down from predecessors. Some authors have
suggested that might mean from Archimedes, but I'm not aware
of what what evidence there would be for this, so
I'm not sure how strong that suggestion is. Maybe it's
just kind of like, oh, Archimedes, he invented stuff, and
maybe it's him. Yeah, I think some sometimes we see
in different traditions we have these these noted inventors, noted minds,
(19:21):
and they kind of become mythic magnets for various ideas
and inventions. But there might be some good reasons for
think of our comedies. I just don't know if there is.
I did not turn it up than the basic principle,
how does this odometer work? So you've got a chariot wheel.
(19:42):
Odometer typically has a wheel of some kind that is
rolling on the ground and that's your your basic point
of contact with the Earth to get the the baseline
measurement of distance. So you've got a chariot wheel of
a fixed size two Roman feet in radius, which Vitruvius
says h gives the wheel a circumference of approximately twelve
(20:03):
point five Roman feet. So if the radius is two,
that's four times pie, which is about twelve point five six.
So when Vitrivius has twelve point five Roman feet, he's
sort of approximating in his explanation. But anyway, each time
the chariot wheel makes a full revolution, it will advance
a cog wheel by one cog position, you know, one
(20:25):
tooth advances and the cog has the cog wheel has
a fixed number of teeth, meaning that it will make
a full revolution once the wheel has traveled one Roman mile.
Every time this cog wheel makes a full revolution, it
will advance a gear that pushes a single small object
like a pebble or a bead into a receptacle. And
(20:47):
then at the end of the journey, you simply have
a human count up the beans, you know, count up
whatever the little pebbles or beads or beans are to
know how many miles you've gone. And I want to
make a note that this seemed interesting to me, that
this is the principle of using a system of gears
as a type of analog computer, similar to the use
(21:08):
of gears in the ancient astronomical computer known as the
Antikithera mechanism. We discussed this in an episode we did
sometime in the past couple of years. It might have
been in the Creature of the Gear episode about biological gears.
But the idea that we often think of a gear
is something that creates mechanical advantage, and it certainly does
(21:29):
do that, but a gear can also manage ratios between numbers,
like a gear can do math for you, and that's
what it's doing in the case of this odometer. Yeah,
I love these these examples of them from the ancient
birth of the odometer or possible birth of the odometer,
and some of these these instances, because it seems it's's
(21:50):
kind of like we have the wheel turning on the road,
and then it's a question of could we put that
wheel to use, Like the wheel is already in a
sense marking the distance in its revolution, and and in
that it's kind of like the heavens. It's like the sun.
It's like the moon, it's like the the cyclical movements
all around us that mark the passage of time. Yeah,
(22:11):
you just need to correlate something with like a fixed
number of teeth that you can count to those pre
existing revolutions, and then you take those teeth to do
some kind of work that will help you keep the count,
like dropping a bean in a bucket, or advancing a
dial to on a fixed face that has a number
printed on it. Yeah, and it and it. You can
imagine that into the in the ancent minds like you
(22:34):
would have realized if we could harness this, like this
is better than than than counting your steps. There's a
regularity to this that would be harder to achieve through
other means. Totally so so. Vitruvius describes a machine roughly
like that. Hero later describes a similar machine, but there
are some interesting differences in how the two authors present
(22:56):
their explication. For example, Vitruvius describes his dodometer with fixed dimensions.
The wheel is four Roman feet in diameter, the circumference
is approximately twelve point five feet, and so forth. And
here I want to read a passage from Roby quote.
Rather than providing a mathematical formula whereby the odometer could
be adapted to any desirable or available wheel size, as
(23:20):
Hero does for his own description of an odometer, Vitruvious
avoids formulas and geometrical language by specifying the wheel diameter
and circumference as fixed numbers. That is to say, the
version of the odometer he gives his reader is presented
as the exact device transmitted from his quote predecessors, not
(23:40):
a jumping off point for experimentation with the type of device.
And she goes on to explain this as typical of
the difference between Latin language technical literature from this period
and Hellenistic technical literature. Works in Latin tended to be
exact descriptions of existing devices rather than demonstrations of principles
(24:02):
and scalable instructions for building new machines. Uh the ladder
the you know, the scalable instructions and explication of principles
is more like what Hero of Alexandria presents. Instead of
having fixed dimensions, his explanation is about how to apply
the idea of an odometer to different scales and uses.
(24:22):
With the numerical figures being ratios rather than measurements. So
Hero's goal was to represent these relationships between the different
sizes of the wheels and the connected gears, and then
to read one final passage from Robi quote. Heroes description
allows mechanical flexibility as well. He suggests how to extend
(24:43):
the number of cogs in the odometer, which can radically
enhance its measuring capacity. On the other hand, he notes
that it is pointless to make an odometer that measures
a greater distance than its vehicle could cover in a
single day, as it is easiest to just start the
count over each warning, which I lay. That's very practical,
(25:03):
but it also it flags an interesting difference here. They're
just different assumptions about the reader uh the text. In
a more Hellenistic tradition, or as as Hero does, it
might be geared more toward a select audience of highly
educated polymaths who would be expected to take the engineering
principle and then vary it to their needs, whereas the
(25:23):
Latin Roman tradition is describing an exact device in a
more accessible way that's easy to replicate but offers less
deep understanding and flexibility. But I wanted to come back
to a kind of a lingering question about Alexander's bematists,
whether they used a mechanical odometer or not. And the
(25:44):
question is which is actually more accurate. You might assume
a mechanical odometer is more accurate, but I've read some
arguments that actually human pacers would be less prone to
error over a long distance than a primitive mechanical device
would be. Now, obviously the best possible scenario would be
(26:05):
like to have the odometer on a modern car. You know,
something that is highly accurate, very well calibrated, a highly
accurate modern device, uh, that that's going to give you
the best reading. But obviously something built in the fourth
century b c. Would have significant enough inaccuracy and its
measurements that this would cause problems over great distances. And
(26:27):
so the idea is that any inaccurate measurement in a
mechanical device would just build up and up over many,
many miles on a great journey, Like if the circumference
of your wheel is slightly too long over thousands of miles,
it will start to significantly underestimate the distance traveled. Meanwhile,
I think the idea at least is that human biobmtists
(26:48):
literally counting their steps will also have inaccuracy, maybe inaccuracy
relative to some reference length of a single pace, but
that inaccuracy will go both ways. Steps that are too
long and then steps that are too short, and those
will average out over time. That's the argument at least,
and I see the logic here, and I admit that
(27:09):
I'm I'm not a genius at statistics, so I could
be wrong. But my reaction is that I think this
could also be mistaken because it would tend to assume
that the human pacers inaccuracy will not be consistently biased
either above or below whatever the reference past length being
used is. Uh So, I think this logic might work
(27:30):
if you had like a group of a thousand people walking,
and then you had all of them count their steps,
and then you averaged all of those together. But if
it was just a single person, I would tend to
think that their personal count might be biased more in
one direction or another. They would just tend to have
longer than average or shorter than average steps, and that
(27:51):
even a pretty primitive machine would be better. But I
don't know. That's fascinating, Yeah, I don't. I don't know
what to make it because yeah, I can. I can
see what they're getting at with the idea that some
sort of a basic mechanical flaw in an ancient odometer
device that you would just consistently get the wrong number,
(28:11):
and then that would build up over time, and then yeah,
when when it comes to the actual steps and the
counting of those steps by an individual or individuals, you'd have,
you know, a little, a little in one direction, a
little another direction, but it would sort of even out. Yeah,
that's that's fascinating to think about. I mean, I think
it would be more likely to even out if you
were talking about a group of people, like a large
(28:34):
group of people all average together. Yeah, I don't know
if that'd be the case for a single person anyway,
whether or not they were using mechanical odometers, ancient dematists
did a not at all bad job of measuring different
distances between milestones between cities, and it's possible they were
helped in this task by devices like the ones described
(28:56):
by Vitruvious and Hero. But ultimately, I think we don't
know for sure if they use these devices or not,
and if they did, we don't know for sure who
invented these ancient odometers. It's it's one of those questions.
You know, there are many inventions where we just don't
know where they came from. I wonder too if it
might have been a situation where they use both where
(29:18):
where their specialist in their field. So perhaps, like specialists
in other fields, they're using more than one method and
then comparing the numbers and figuring out some sort of
more accurate measurement based on the two. Yeah, that could be.
I don't know. But anyway, it's really impressive that in
the what it's like the third or fourth century b c.
(29:39):
We've got people getting like really accurate estimates of of
travel distances that are on the order of hundreds of miles. Yeah,
that's fascinating. Now, all of this is going on in
the Greco Roman world, but as we've partially alluded to already,
there's there's also a history of the odometer in Chinese
civilization as well. In particular, the device in question is
(30:04):
the Lee recording drum carriage. Now, this is sometimes attributed
as an invention of Zongheng, who lived at seventy eight
through one c E. This is a Chinese polymath and
court astronomer in the Eastern Han dynasty. Uh. This is
an individual we've talked about before because there are a
(30:25):
number of different inventions that are attributed to him, one
of which was an early form of earthquake detection device. Uh.
He had an important role tending calendars and celestial events,
aiding the Emperor Um, who of course ruled at the
mandate of Heaven, so, you know, maintaining the balance between
cosmos and civil life. And this is a period of
(30:49):
time that sometimes referred to as the Golden Age of
Chinese history, for centuries of economic prosperity, that's all the
traffic of goods and ideas across the Silk Road. He
was an inventor, a poe it in an Early Scientist.
We have an older invention episode about the earthquake detection device.
And I was looking back at some of our notes
and I'm reminded that that you shared some of his
poetry in that episode. Oh I don't remember that now.
(31:13):
Was it good poetry? Oh? Yeah, yeah, that's good stuff. Um.
So he's credited with a number of inventions, innovations, and achievements.
He wrote a treatise on the Mystical Laws of the Cosmos,
which included the theory that the moon did not emit light,
but reflected the light of the sun. And he's also
sometimes attributed as the inventor of the Lee recording drum carriage,
(31:33):
which again is this um uh, this this odometer of
sorts in Chinese history. Now it is worth noting that
that kind of like the situation with Hero and Archimedes,
we have a very famous historical inventor here, and he's
attributed with a number of inventions. And so I guess
the question always lingers, is this an invention that this
(31:55):
individual invented? Is it something that they described it something?
Is it's something that just ends up being attributed to
them because the technology was known during that time, or
it's based on surviving records, etcetera. Yeah, exactly. So I
ended up looking at some of the writings of Joseph
need Him on this. So Needham lived. He was a
(32:19):
British biochemist, historian of science and sinologists who wrote rather
extensively on the history of science and technology in China.
His second wife, lu gives him was a Chinese historian
and biochemist, and she was an important co researcher and
co author in his work. So we're talking multiple volumes
that he wrote during his lifetime, very very much his
(32:42):
life work. So before we get to the carriage itself,
I thought we might stop to just consider Rhodes in
ancient China. So Needham writes about Rhodes in general in
the short Science and Civilization in China, and he points
out that they were quite comparable to the famous roads
(33:02):
of the Romans. Both empires had extensive road systems that
served as a means of logistically connecting their vast land
holdings for travel and trade as well as you know,
playing an important part is just in just communication through
the empire. That's always something to keep in mind, uh,
that the road is also a lane for communication. Now,
(33:24):
both systems, the Roman and the Chinese, fell into long
periods of decay after the third century see he points out,
though he writes that while the collapse of Roman roads
had more of a fracturing effect in China, natural and
artificial waterways and some surviving mountain road systems enabled these
far reaching routes of communication to remain open. He also
(33:46):
points out something very interesting about these two independent systems,
that it's this rather on inspiring and I thought really
nicely written. And it also kind of ties into some
of the stuff we talked about in our previous episode
about the Roman military that the Dethrone Emperor series quote.
Should the Romans have ever succeeded in conquering the Parthians
(34:06):
and the Persians, the two road systems might have met,
perhaps somewhere west of shin Jiang, but this was not
to be. The octopus like arms expanded independently, each in
a world of its own, their builders, troubled only occasionally
by the vaguest rumors of another system too far away
(34:26):
to matter. It's in John, by the way, is in
northwest China. That's where he's talking about here. So, yeah,
this is such a I love this quote because it's
just a imagining these two independent road systems, like like
like octopuses, Uh, each doing their own thing. And if
you know, world history had gone a different way, there
could have been a situation where they met. Uh. It's
(34:49):
it's crazy to think about, like like roads, I've often
thought about. You know, you encounter a road and where
does that road end? You know that basically goes It's
not infinite, but uh, you can it stretches on for
such a great distance. And to imagine these two vast
systems um almost but not quite coming together. Yeah, it's
(35:09):
kind of like I don't know if if you've ever
played around with this to to see like how far
one can drive on a given continent or on connected continents,
Like at what point do things seem to break down
and you would have to find some other route to
connect with another road? And I know when you get
into Eurasia and Africa, like there are some pretty long
(35:29):
travels by road that are that are possible today. The
road is not going to be necessarily to be great
the whole way, but you can do quite a lot
thank so. Anyway, Needham points out that with the odometer
or the way measure, it's it's a pretty simple proposition
(35:51):
from a mechanical standpoint. If you have the wheel already,
and you have row, and you have if you have roads,
you have wheels, then all it is is quote a
system of toothed wheels constituting a reduction gear train so
that one or more pins revolved slowly, releasing catches at
predetermined intervals, and in the case of this invention, striking
(36:12):
drums or gongs, so the lee recording drum carriage. What
is Alie Alie is the traditional Chinese measure of distance today,
standardized at five meters or one thousand sixty feet, but
as with a mile and Western traditions, historically there's some
drift over exactly how far it is supposed to be.
(36:34):
But it's standardized today and would have been standardized under
different rules and different dynasties. Yes, standardization of measures does
seem like such an important part of this too, because
I when I kept thinking about the idea of of
a bimitist potentially trying to measure distance with paces, I'm like,
what is So You've got to have something that's like
(36:55):
a reference pace, right, If you say something is x
number of paces long, you've got to either know how
much your pace typically relates to a standard measure like
a mile, or you've got to be using your paces
as some kind of literal standard measure, like people would
know what that number meant. Yeah, yeah, it's yeah. The
(37:17):
the history of of measurements alone would be something interesting
to come back to, because, of course you get into
use of various parts of the human body uh to
to form your base measurements, UH, the creation of tools
and UH and certainly when you're getting into weights for
goods and trade, like some of our oldest data and
oldest examples are all related to that. But then when
you start thinking about these larger measurements, like the measurement
(37:40):
between you know, the fourth in the frontier, that sort
of thing, like you like, you can't just count, You
can't just have someone go out there with essentially a
ruler and say all right, start measuring it off, like
you've gotta have some other system. Yeah, yeah, alright, So
Needa gets more into into the subject of the lea
the Lee measuring art here in Science and Civilization in China,
(38:02):
Volume for Physics and Physical Technology, Part two, Mechanical Engineering, Um,
and yeah, it gets into the nature and origins of
the Lee recording drum carriage. He cites several sources and
post in some of these resources that go into more detail.
Others just kind of mentioned it in passing and points
out that that many of the mentions of the carriage, yeah,
(38:23):
they don't actually describe the mechanism employed. In at least
one case, it shows up as a math problem. It's
it's something along the lines of if the Lee recording
drum carriage were to travel between this city and this city,
how many times would the gong u sound that sort
of thing. The concept seems to date back to the
Hun dynasty, and this is where the attribution to zong
(38:44):
Hang seems to come into play. But when the carriage
is described, it's generally described as a carriage drawn by
four horses, and it works based on multiple cogged wheels,
some vertical and some horizontal, you know, all of course,
much like the earlier example in the Greco Roman traditions
we were discussing, you know, it's tied to the movement
(39:04):
of the wheels. In the simpler version of this um
of this carriage, it's said that there is a wooden
man in the carriage who is mechanically made to strike
a drum with the passage of each lee. So the
wheels are turning, the cogs are turning, there's a mechanical
wooden man inside who like like a music box, he
(39:27):
is going to mechanically strike a drum in this case,
every time one lee has passed. Beat that vitruvious. You
did not have a wooden man, did you. Later, a
more complex version is described as being two stories in heights,
So so it's a carriage that has two stories and
each story has its own wooden figure. The lower figure
(39:50):
strikes a drum every lee, while the higher figure rings
a bell every ten le Okay, So one difference that
occurs to me here is this would still if it's
keeping track of the distance in an accurate way, but
doing so by making a sound instead of by say,
accumulating uh, pebbles or beads in a container. It's something
(40:14):
that you would to some extent need to continuously keep
track of as you're traveling, Like it would still require
effortful engagement of the memory by somebody doing the traveling, right,
That's right. That's based on my reading here of need him.
I don't think there's any indication that it was spitting
out like you know, balls or or or or pebbles
(40:36):
that could then be counted later, or there was anyway
recording how many leaves it passed. It was just a
you know, a ringing of a bell or the striking
of a drum based on the intervals traveled, which would
still be useful, but would require more work than or
at least work spread out over a longer period of time,
rather than say like a single counting activity in between
(40:59):
travel segments. And in this we get into one of
the big questions about the Lee recording drum carriage, and
that is was this a device that was at all
originally intended to measure distances? Or was it you? Or
was it more about music? Was it more about novelty?
(41:19):
Was it was it? Why was the technology employed? So
again this was this? These writings are typically revolving around
the Han period or perhaps a little earlier, but the
Lee measuring drum carriage was not known as such until later,
and need Him discusses that this might mean that the
invention was in fact more expressly for musical performance rather
(41:39):
than the measurement of distances. Again, at least during this
time period. It may have may have changed later when
someone realized, oh yeah, we can just count how many
strikes of the drum, we can count how many rings
of the bell, and then that's data that could prove useful.
But he stresses that you know, these are still interconnected,
interconnected possibilities, um. And if you're if you're asking, well,
(42:01):
why would they do that, like why build a carriage
like this? And why does it remain something other than
just like a one time novelty, Like why is it
written about so much? And he points out that music,
of course, is often part of a procession, and he
stresses that quote carriages for musicians, whether mechanized or not,
survived in imperial processions through many subsequent dynasties. So the
(42:24):
idea here is that the mechanical version uh here develops
from non mechanical carriages with human musicians inside them. Imperial
fleets of vehicles, as he refers to them, would have
likely included palace officials and so forth, but also entertainers musicians.
So as everyone's traveling down the road, there's music, and
(42:47):
at some point someone says, hey, what we could We
could build some gears. We could make a mechanical musical
man inside one of the carriages, putting those flesh musicians
out of the job. Well, I don't know if they've
become cletely out of the job, because you know that
these these mechanical musicians can only do so much here.
But but yeah, for for a modern comparison, we might
(43:07):
think of of a parade float as a as a
counterpart is something like this. It does sound a lot
like a parade float. It would have been, according to
one account, painted red and decorated with flowers, and birds it.
It's described as being escorted by eighteen men. Uh, and
there would have been a phoenix headed carriage pole on it.
So this was not clearly not something that was like
(43:29):
a Google Maps vehicle that was out there just to
perform a task. It Also it said that it looked marvelous.
It's a joyous vehicle. And once more, Needham stresses that
we don't know for sure if it was ever used
by cartographers. Uh. It's possible that that later on photographers
may make use of the data that could be provided
(43:50):
by this, but we're not sure. Interesting, so Needham points
out that heroes description of the podometer did not claim
it as a new invention. He mentions the truvious and
then mentions that after hero Vitruvius, the odometer appears in
Western Europe during the fifteenth century, so it's it's kind
of not really on the Western European radar for a
(44:10):
long period of time, or doesn't seem to be based
on surviving histories, and then it re emerges. Quote. The
pattern is therefore the same as that which we have
repeatedly met with i e. Greek antecedents paralleled or followed
by followed at short distance by Chinese developments which continue
throughout the medieval period, and then a reawakening of the
(44:32):
subject in Europe. So in this he's touching on something
that was kind of a career spanning question for him.
Is often referred to as the need Him question, and
that the question is basically why didn't China beat Europe
to the scientific revolution. He's been a fair amount of
his work thinking over this and looking to answers and
Chinese social institutions and more. Uh though, as as of reading,
(44:55):
the psychologist Nathan Siven, who would have been I think
at times of liberator with Needham, pointed out that, you know,
the whole thing is basically a why did an X happen?
In history question, which by some estimates is less than
a fruitful enterprise. You know, you get into all sorts
of complex butterfly wing flapping concerns when you start asking
(45:16):
questions like that. They can be kind of nifty head scratchers,
but perhaps they are not the best exercise for an historian.
But at any rate, the Needham question, you see it
mentioned a lot in discussions of of the history of
Chinese science. Now, I do want to note in reading
about all this I also read as some material for
(45:37):
needum about another interesting wheeled vehicle in Chinese history, and
that is the south pointing chariot. But that's one we're
gonna have to come back to. But yeah, the idea
of a chariot with another mechanical man on it, but
this mechanical man always points south omous. Okay. So we're
not gonna We're not gonna go through the exhaustive history
(45:59):
of the of the odometer in in recent centuries, but
I thought it might be useful to point out a
few different later innovations that kind of bring us up
to the modern odometer. Um, there's Pascal's calculator. This would
have been an invention or an innovation by Blaze Pascal. Uh.
This was five not an adometer per se, But it
(46:22):
was a computation mechanism that entailed rotating toothed gears, and
much like a modern odometer, one complete cycle of one
gear caused the movement of the next gear. Okay, So
this would have been taking the same principle by which
the ancient odometer worked, but applying it to general calculation
rather than just the movement of a vehicle wheel. Right now,
(46:44):
in the late sixteen early seventeen hundreds, we also see
Thomas Savory's nautical odometer. Uh. Savories most famous invention was
the steam engine, but he also devised a nautical adometer.
I actually couldn't find out much about this, so I
don't know. I'm gonna have to come back to this
one in a few sure, but because I was curious
on how exactly it would have functioned. Interesting. Yeah, supposedly
(47:05):
there was a patent, so it seems like I should
be able to find that patent somewhere. So I don't know,
I have to come back to that one. But this
is a fun part because our old friend Ben Franklin
also enters the fray here when it comes to the odometer.
He's come up in more than one invention conversation, I believe.
So what what was his take? So? In seventy five
(47:27):
he was serving as Postmaster General for the British. Previously
he had been postmaster of Philadelphia, and he wanted more
data on the shortest routes for mail delivery. So he
basically devised a simple odometer to attach to his own carriage.
And UH, and this will for this reason you'll sometimes
see especially some online sources saying Ben Franklin invented the odometer. No,
(47:52):
it's not accurate in the least to say Ben Franklin
invented the odometer. You could say he invented on odometer.
He certainly would one up on the fly here. It
seems so every four revolutions it would register a mile
and the results were apparently pretty accurate based on what
I was reading here. So at any rate, he was
able to to to use the data, uh, to figure
(48:14):
out which route was best for male delivery. Now, one
thing I know I saw reference to on the internet
and I didn't know what to make of this was
the idea of a Mormon odometer. Yeah, this was one that, Yeah,
that came up for me as well. The rhodometer from
Clayton and Pratt. Uh. This would have been eighteen forty seven.
(48:34):
They were pioneers of the Church of Jesus Christ of
Latter day Saints and they apparently crafted a simple odometer
to measure how far a wagon train had traveled. Um.
So that's it's interesting again. It's we're getting into this
area where it sounds like people would find themselves in
situations where they could really use an odometer, and since
the knowledge was was known, you could create one. You
(48:57):
couldn't go to the store and buy one, but the
principles route there. The principles were part of of of
of the technological canon, so you could draw on that
and make yourself a functional odometer. In e Curtis age
Vter came up with a bicycle mounted odometer, the cyclometer,
and then in three we have the Warner autometer, which
(49:20):
I think, like the advertised versions of this, this was
like an actual product. It was a combined odometer, spedometer,
and clock, but it made use of magnetism as opposed
to just pure gear work. Uh So, like those are
some of the big more big innovations in the odometer
in recent centuries. And uh yeah, today the odometer again
(49:41):
is something we tend to just take for granted or
we don't even read it. It just sort of clicks
by there and maybe we check in on it every
you know. However, many thousands of miles, I guess at
vary some people were probably more more into keeping a
close eye in their odometer, or you have to for
work obviously. I think about seeing those surveyors who have
the wheel they use the surveyors the surveyor's wheel. Of course,
(50:03):
I didn't think about that. That that's an obvious um
innovation to compare to some of these discussions of the odometer,
like harnessing the power of the wheel from measurement. All right, well,
we're gonna go and close it out here, but we'd
love to hear from everyone out there. Perhaps you have
particular thoughts about the odometer. It's ancient history, it's recent history,
or or you know, our modern use of the technology
(50:26):
right in we would love to hear from you. As
a reminder, our core episodes of Stuff to Blow Your
Mind publish on Tuesdays and Thursdays, and the Stuff to
Blow Your Mind podcast feed on Monday's we do listener mail,
on Wednesday's we do a short form artifact or monster fact,
and on Friday's we do Weird How Cinema. That's our
time to set aside most serious concerns and just talk
about the strange film huge thanks to our excellent audio
(50:47):
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Blow Your Mind is production of I heart Radio. For
(51:10):
more podcasts for my heart Radio, this is the i
heart Radio app, Apple Podcasts, or wherever you listening to
your favorite shows,
Welcome to Stuff to Blow Your Mind production of My
Heart Radio. Hey you welcome to Stuff to Blow Your Mind.
My name is Robert Lamb and I'm Joe McCormick. Today
Unstuffed to Blow your Mind, we have another invention themed
episode for you. We're gonna be talking about something that
(00:24):
might initially seem frightfully dull or at least very commonplace,
and that is the odometer. I mentioned this to Rachel
earlier and she was like, oh, yes, the device that
measures odors. Yes or odo's. If you were to read
the word wrong, you might think it says autometer, um,
but it's yes, the odometer. So everyone other you probably
(00:45):
know this device best is the little counter in your vehicle,
the records how far you've driven. And I think we
tend to think of this invention mostly as a self
centered device. It tells us how far we've driven on
our trip, how many miles or kilometers we've racked up
on our vehicle. But you know, there's another way of
looking at the odometer, and this, certainly this is something
(01:07):
that plays into and into the history of the invention
and also our attempts to understand its place in the
ancient world. Is that an odometer can also be a
method of determining distances on given routes. It's something that
turns a vehicle into a tool from measurement, right, So
it's it gives you information that would be useful to
(01:30):
other people, because I mean, in the ancient world, you
don't have Google Maps or anything. You might know that
there are two cities, and you might know that you
get from one of them to the other by following
the road to the west, but you might not know
how long it's going to take you to get from
one to the other. So it would be very useful
if you actually had some standard distance measurements that would
(01:50):
allow you to estimate the length of the journey and
to know how much you need to pack for the
journey and so forth. Yeah, we've talked before about the
some of the the important things that make up an
empire and make an empire or a kingdom function, and
there are things like standardized measurements, of course, and standardized currency.
But another thing that would be useful is indeed, like
(02:13):
you say, to know how long it takes to get
from one place to another, what is the distance from
one place to another, from border to border from port
to capital, from frontier to ford and sofa forth. And
this is the kind of thing that would of course
be important for warfare, but also for trade and just
general management of a given territory. So on one hand,
(02:35):
you can imagine this situation, and you can and you
can think about what an odometer is, and knowing that
an odometer has uh some of its history in the
ancient world, you might think, well, this is the this
is the route we take to get to the invention.
This is the necessity, uh that is the mother of
this invention. But this doesn't necessarily seem to be the case,
as we'll discuss, as we look at at its history
(02:57):
both in the east and in the west. Now, I
think it's worth thinking at least just a little bit
about maps and cartography here, because it's easy for for
the mind to go there, like I need to know
the exact distance between X and Y because I want
an accurate map, right, Uh. To kind of go hand
in hand when we think about maps today, Like even
if I'm looking through a Dungeons and Dragons book, I
(03:19):
have a map of some sort of fantastic region, and
then I have a little indicator to tell me exactly
how how many miles and inches or something to that effect. Oh,
once you get into D and D, though, I feel
like it's often very loosey goosey about travel distances. Oh yeah,
and um and as a when I am dungeon mastering,
I I am also I hate it when there's like
(03:40):
a really specific question about distances, like, well, is it
is it one mile or two mile? It's like, I
don't know, it's just it's however long it takes to
get there. But any well, my experiences, you want to
you want to take a queue from the d M
basically like, is this a journey where things will happen
on the journey or a journey where we will just
magically arrive at the destination? Yes, sometimes the magic is
(04:03):
in the journey, but sometimes it most definitely is not.
So thinking about this the situation about figuring out knowing
what the distances are between one place in the other,
and thinking about the role of maps in the ancient world.
I turned to one of my my favorite go to
text for a lot of this sort of thing, Brian
Fagan's The seventy Grade Inventions of the Ancient World, And
there's a there's several different chapters in there, the deal
(04:25):
with measures and maps. Uh and of Fagin and his
co authors point out, I think a few important things
about ancient maps that we might want to have in
our head as we proceed. So, first of all, they
point out, the Chinese maps of old were more about
landscape features. So the journey from X to Y is
more about the details of the landscape and the markers
(04:49):
that are passed on the way. Yeah, that makes sense,
navigating by landmarks. Yeah, and so the maps would reflect that.
Another thing they point out is that while local maps
in the ancient world we're one thing, as we're specialized maps,
broader maps of the world or region, we're not really
part of the overall ancient approach to maps. There were
(05:09):
no regular standards of map making, and there were no
general purpose maps. And uh, this is one quote from
the book I thought was rather telling quote between them rulers, generals, sailors,
and traders evidently all but ignored the practical assistance that
maps could afford them. That's surprising. Yeah, I mean hindsight
(05:31):
twenty but uh, yeah, it's interesting to look back and
think about what benefits this broader approach to maps general
purpose maps, etcetera. Could have afforded them, So I think
all that's worth keeping in mind as we proceed here.
None of this is to say peoples during these eras
were not concerned with precise distances, but the relationship with
(05:51):
exact maps wasn't quite the same as what we have
now now. Another way of thinking about what came before
is that there certainly were ways of measuring long distances
before the invention of the mechanical odometer. Though there is
some question about the relative accuracy of early mechanical methods
versus pre mechanical methods, and one case study here that
(06:14):
I think we should look at. It's very interesting puzzle
that emerges if you look at a geography chapter of
The Natural History by by our old friend Plenty of
the Elder. Here I'll be referring to the Bostock and
Riley translation for those not familiar. Plenty of the Elder
was a first century Roman military commander and author, and
(06:36):
the Natural History is an early attempt at creating a
sort of world encyclopedia. So Plenty covers everything from mining
and metallurgy to botany and zoology, cooking, politics. It's just
it's just a book of everything, and in book six
of the Natural History, Plenty sets out to describe, quote,
(06:57):
an account of countries, nations, sees to ounds, havens, mountains, rivers, distances,
and peoples who now exist or formerly existed. Very good
chapter heading there. One of the chapters within this volume,
chapter twenty one, is on the nations of India, as
known to Plenty at the time. Again, this is the
(07:17):
first century CE. So Plenty says that India is a
vast country with over a hundred kingdoms, dozens of rivers,
uncountable mountains, but he will undertake to describe some of
it by following the path of Alexander the Great, who
led a conquering army to India about four hundred years earlier.
(07:38):
So Plenty rights quote, however, that we may come to
a better understanding relative to the description of these regions.
We will follow the track of Alexander the Great. Diagonitis
and Biton, whose duty it was to ascertain the distances
and length of his expeditions, have written that from the
Caspian Gates to hecatom Pylon, the city of the Ptarthians,
(08:01):
the distance is the number of miles, which we have
already stated and he mentioned a number earlier, and then
he goes on and that from thence to Alexandria of
the ri I, which city was founded by the same king,
the distance is five hundred and seventy five miles, and
from thence to Prophesia, the city of the drag Ni,
one hundred and ninety nine miles. And from here he
(08:24):
just goes on and on, listing distances. It's this many
miles to the next city, and this many miles to
the next city. Uh. So he attributes all of these numbers,
all of these distances and miles that he comes up
with for this path leading into India to these two figures,
Diagnetis and Biton. Who were these guys well, they were
(08:46):
known as Bimatists, coming from the Greek word meaning step
or pace. I looked up Bimatists in the Oxford Handbook
of Classics, and the entry does identify them as the
the surveyors essentially of Alexander the Great Uh and names
a few other ones. In addition to the two already
(09:06):
mentioned Byton and Diagnetus. It also names uh Philonides of Crete,
who it says in a side note, was a celebrated
distance runner, and the entry also notes that the two
figures who worked for Alexander, Byton and Diagnetus, as well
as some others quote had literary aspirations. Their measurements of
(09:27):
key distances in the empire comprised an archive later controlled
by Seleucus. The first individual Bemetists published their observations in
monographs termed stath moy or Stages, which combined precise calculations
of distance with more exotic reports of the flora, fauna,
and customs of the empire. The latter tended to the outrageous,
(09:50):
but the measurements were of lasting value and provided Eratas
the Knees with the framework for his geography of Asia.
Aretas the Nees, you might recall, was an really figure,
a Greek philosopher who with pretty startling accuracy, calculated the
actual size of the sphere of the Earth. And he
(10:11):
did that just using knowledge of the distances between locations
of different latitudes and then the use of the angles
of sundials. Basically, yeah, So, how did the Bematists actually
measure distances in the time of Alexander the Great? Well,
I've seen some disagreement on this, some sources imply that
(10:33):
they simply counted paces, so you'd walk and count how
many steps you took, while others suggest that they used
some kind of mechanical device. One of the weird things
is that, as far as we can tell, most of
the distances recorded by bematists such as Biton and Diagnetis,
as well as others from the ancient world, are surprisingly accurate.
(10:56):
On this point, I want to quote a book I
was looking at by a American historian named Donald W. Ingalls.
The book is called Alexander the Great and the Logistics
of the Macedonian Army from the University of California Press
in nineteen seventy eight. And explaining a table in his
book of the bimatists different estimates of the distances between
(11:17):
cities on this route, ingles rights quote the overall accuracy
of the bimatists measurements should be apparent. The minor discrepancies
of distance parentheses only one point three percent from herat
to begrum, can be adequately explained by slight changes in
the tracks of roads during the last twenty three hundred years.
(11:38):
The accuracy of the measurements implies that the bimatists used
a sophisticated mechanical device for measuring distances, undoubtedly an odometer,
such as described by Heron of Alexandria. So there's a clue.
Uh Ingles here says, Look, the distance is given by
these these people who worked for Alexander the Great and
(11:59):
other immotists of the era. They're just too accurate. They're
too good to be the result of trying to count
your steps and estimate from that. They have to be
using some kind of machine that we don't know about,
and one good candidate is a machine like the one
described later by Heron of Alexandria. Now, this idea that
they may have simply been walking, on one hand, I
(12:22):
can't help but think of the Monty Python ministry of
silly walks and imagine like a specific, ridiculous but regular
date that they're using, and and if they were super
focused on their steps and counting their steps, maybe that
would explain why they're reports of flora and fauna are
so outrageous. They're like, well, I was it was. It
(12:43):
was three thousand, eight hundred and seventies six steps. And
to the left there may have been a dragon. I'm
not sure. I was just really focused on these steps
and getting the step count right. I mean, descriptions of
local flora, fauna, and people's of the world are notably
hilarious throughout all kinds of ancient texts, including Plenty himself.
(13:04):
He loves to talk about people who had like eyes
in their stomachs and stuff. Yeah. I keep hoping one
day I'll come across a passage in Plenty where he
mentions people who have crab clause. I haven't found that yet. Oh,
I have to have to look into that, I mean,
because you mentioned it's it's of course not just Plenty
in his writings and travelers that he's sourcing, and we
we've discussed similar things in Chinese traditions as well, So
(13:26):
there have to be some crab claude individuals out there somewhere.
But okay, sorry to Hero or Heron of Alexandria. Multiple
sources I found point to a device described by this
first century mathematician and inventor, sometimes known as Hero, sometimes
known as Iron, but he was from Alexandria, Alexandria, Egypt.
As you can tell by the name. A lot of
(13:48):
inventions are attributed to Hero, though some of the most
famous ones probably predated him, and he just described them
in lectures and writings, and then later that gets sort
of mistaken for him having actually invented the thing in
the first place. In the latter category. One example, in fact,
one of the most famous devices associated with Hero is
(14:10):
the Yala pile, which is a type of early steam
engine converting the power of steam into rotational energy. Basically
it works, but you've got a big cauldron this full
of water, and then you put a fire underneath it,
and then that cauldron is connected by pipes to a
sphere that can rotate around the pipes, and then the
(14:31):
sphere has two little exhaust nozzles that allow steam to
escape as the water boils and turns into steam and expands.
But the way the nozzles are oriented, they're oriented in
the same rotational direction, so as the as it gets
hotter and hotter and the cauldron and the steam pressure
builds up, it spins the sphere faster and faster. Yeah,
(14:54):
there are a lot of images of this, as I recall,
I remember seeing a cool woodcut of this, I think
at one point um but it has a look of
of a novelty of a device that's that's illustrating the
principle here, but but of course not putting it to
the sort of work that later UH steam engines would.
For sure. Yes, and though the e Allo pile is
(15:16):
often associated with UH, with Hero, I think this is
something that he very likely did not actually invent. It
was just something he described that already existed. UM. But
we have talked about other machines possibly invented by Hero
in previous episodes. One that I remember is the Hero
of alexandrias In is credited with inventing the first vending machine,
(15:39):
which strangely was also a piece of religious technology. It
was a machine designed to dole out limited portions of
sacred water within Egyptian temples when a devotee would insert
the right amount of coinage. So I think you'd put
a five drachma or five drama piece in through a
coin slot, and then that would operate a weighted lever
(16:01):
that would dispense a certain amount of holy water, and
then once a certain amount of water had gone out,
the machine would tip over and then it would close
the valve and stop dispensing. Though even in this case,
I read that it's actually possible Hero was simply describing
a device that had already been invented by two Cbs
of Alexandria in the third century BC. So, as with
(16:22):
a lot of ancient inventions, it's often hard to tell
if somebody actually invented something or if they're just talking
about something that already existed. Anyway, I found multiple references
to Hero either inventing or describing an odometer, as evidenced
by a passage he wrote in a minor work called
the Dioptera, which I wanted to find the full text for,
(16:44):
but if it has been translated into English, I was
unable to find it, so I don't know if that
even exists in English. But regarding this, this machine he
describes in the diopter again, the Hero is first century CE.
A couple of caveats. One is that he Hero was
definitely not the first known author to describe an odometer
in Greek. In the Greek and Latin Corpus, the Roman
(17:07):
engineer Vitruvius, who lived in the first century BC, so
century before Hero, also describes an odometer, uh, though in
a slightly different way. I'll get into the differences in
a minute. But even Vitruvius does not claim to have
invented the device out of whole cloth. And then there's
a second caveat which is that remember again Ingles making
(17:29):
the comment that Alexander the Great's bimatists must have had
a device like Heroes. The problem here is that hero
of Alexandria and Vitruvius both lived along after the conquest
of Alexander the Great. So if it's true as Ingles
suggests that these bimatists used a mechanical odometer similar to
the one described by these engineers and authors, they would
(17:52):
have been using some kind of earlier device similar to
Heroes or Vitruvious. Is not something that hero or Vitruvious
and vented. Now. An interesting source I found on on
these two device descriptions is a book called Technical Exprassis
in Greek and Roman Science and Literature, The Written Machine
(18:13):
between Alexandria and Rome. This is by an author named
Courtney Roby from Cambridge University Press. Courtney Roby is a
professor of classics at Cornell and in this book, this
is in the context of explaining patterns of composition in
Greek and Roman technical books, how in different times and
(18:33):
cultures there were different standards and uses for technical explanation
of machinery. Hero and Vitruvius both wrote books describing odometers.
I mentioned Heroes, but the the earlier mentioned by Vitruvius
comes in a book called on Architecture, and according to Roby,
Vitruvius himself acknowledges that the odometer is quote part of
(18:56):
a technological tradition handed down from predecessors. Some authors have
suggested that might mean from Archimedes, but I'm not aware
of what what evidence there would be for this, so
I'm not sure how strong that suggestion is. Maybe it's
just kind of like, oh, Archimedes, he invented stuff, and
maybe it's him. Yeah, I think some sometimes we see
in different traditions we have these these noted inventors, noted minds,
(19:21):
and they kind of become mythic magnets for various ideas
and inventions. But there might be some good reasons for
think of our comedies. I just don't know if there is.
I did not turn it up than the basic principle,
how does this odometer work? So you've got a chariot wheel.
(19:42):
Odometer typically has a wheel of some kind that is
rolling on the ground and that's your your basic point
of contact with the Earth to get the the baseline
measurement of distance. So you've got a chariot wheel of
a fixed size two Roman feet in radius, which Vitruvius
says h gives the wheel a circumference of approximately twelve
(20:03):
point five Roman feet. So if the radius is two,
that's four times pie, which is about twelve point five six.
So when Vitrivius has twelve point five Roman feet, he's
sort of approximating in his explanation. But anyway, each time
the chariot wheel makes a full revolution, it will advance
a cog wheel by one cog position, you know, one
(20:25):
tooth advances and the cog has the cog wheel has
a fixed number of teeth, meaning that it will make
a full revolution once the wheel has traveled one Roman mile.
Every time this cog wheel makes a full revolution, it
will advance a gear that pushes a single small object
like a pebble or a bead into a receptacle. And
(20:47):
then at the end of the journey, you simply have
a human count up the beans, you know, count up
whatever the little pebbles or beads or beans are to
know how many miles you've gone. And I want to
make a note that this seemed interesting to me, that
this is the principle of using a system of gears
as a type of analog computer, similar to the use
(21:08):
of gears in the ancient astronomical computer known as the
Antikithera mechanism. We discussed this in an episode we did
sometime in the past couple of years. It might have
been in the Creature of the Gear episode about biological gears.
But the idea that we often think of a gear
is something that creates mechanical advantage, and it certainly does
(21:29):
do that, but a gear can also manage ratios between numbers,
like a gear can do math for you, and that's
what it's doing in the case of this odometer. Yeah,
I love these these examples of them from the ancient
birth of the odometer or possible birth of the odometer,
and some of these these instances, because it seems it's's
(21:50):
kind of like we have the wheel turning on the road,
and then it's a question of could we put that
wheel to use, Like the wheel is already in a
sense marking the distance in its revolution, and and in
that it's kind of like the heavens. It's like the sun.
It's like the moon, it's like the the cyclical movements
all around us that mark the passage of time. Yeah,
(22:11):
you just need to correlate something with like a fixed
number of teeth that you can count to those pre
existing revolutions, and then you take those teeth to do
some kind of work that will help you keep the count,
like dropping a bean in a bucket, or advancing a
dial to on a fixed face that has a number
printed on it. Yeah, and it and it. You can
imagine that into the in the ancent minds like you
(22:34):
would have realized if we could harness this, like this
is better than than than counting your steps. There's a
regularity to this that would be harder to achieve through
other means. Totally so so. Vitruvius describes a machine roughly
like that. Hero later describes a similar machine, but there
are some interesting differences in how the two authors present
(22:56):
their explication. For example, Vitruvius describes his dodometer with fixed dimensions.
The wheel is four Roman feet in diameter, the circumference
is approximately twelve point five feet, and so forth. And
here I want to read a passage from Roby quote.
Rather than providing a mathematical formula whereby the odometer could
be adapted to any desirable or available wheel size, as
(23:20):
Hero does for his own description of an odometer, Vitruvious
avoids formulas and geometrical language by specifying the wheel diameter
and circumference as fixed numbers. That is to say, the
version of the odometer he gives his reader is presented
as the exact device transmitted from his quote predecessors, not
(23:40):
a jumping off point for experimentation with the type of device.
And she goes on to explain this as typical of
the difference between Latin language technical literature from this period
and Hellenistic technical literature. Works in Latin tended to be
exact descriptions of existing devices rather than demonstrations of principles
(24:02):
and scalable instructions for building new machines. Uh the ladder
the you know, the scalable instructions and explication of principles
is more like what Hero of Alexandria presents. Instead of
having fixed dimensions, his explanation is about how to apply
the idea of an odometer to different scales and uses.
(24:22):
With the numerical figures being ratios rather than measurements. So
Hero's goal was to represent these relationships between the different
sizes of the wheels and the connected gears, and then
to read one final passage from Robi quote. Heroes description
allows mechanical flexibility as well. He suggests how to extend
(24:43):
the number of cogs in the odometer, which can radically
enhance its measuring capacity. On the other hand, he notes
that it is pointless to make an odometer that measures
a greater distance than its vehicle could cover in a
single day, as it is easiest to just start the
count over each warning, which I lay. That's very practical,
(25:03):
but it also it flags an interesting difference here. They're
just different assumptions about the reader uh the text. In
a more Hellenistic tradition, or as as Hero does, it
might be geared more toward a select audience of highly
educated polymaths who would be expected to take the engineering
principle and then vary it to their needs, whereas the
(25:23):
Latin Roman tradition is describing an exact device in a
more accessible way that's easy to replicate but offers less
deep understanding and flexibility. But I wanted to come back
to a kind of a lingering question about Alexander's bematists,
whether they used a mechanical odometer or not. And the
(25:44):
question is which is actually more accurate. You might assume
a mechanical odometer is more accurate, but I've read some
arguments that actually human pacers would be less prone to
error over a long distance than a primitive mechanical device
would be. Now, obviously the best possible scenario would be
(26:05):
like to have the odometer on a modern car. You know,
something that is highly accurate, very well calibrated, a highly
accurate modern device, uh, that that's going to give you
the best reading. But obviously something built in the fourth
century b c. Would have significant enough inaccuracy and its
measurements that this would cause problems over great distances. And
(26:27):
so the idea is that any inaccurate measurement in a
mechanical device would just build up and up over many,
many miles on a great journey, Like if the circumference
of your wheel is slightly too long over thousands of miles,
it will start to significantly underestimate the distance traveled. Meanwhile,
I think the idea at least is that human biobmtists
(26:48):
literally counting their steps will also have inaccuracy, maybe inaccuracy
relative to some reference length of a single pace, but
that inaccuracy will go both ways. Steps that are too
long and then steps that are too short, and those
will average out over time. That's the argument at least,
and I see the logic here, and I admit that
(27:09):
I'm I'm not a genius at statistics, so I could
be wrong. But my reaction is that I think this
could also be mistaken because it would tend to assume
that the human pacers inaccuracy will not be consistently biased
either above or below whatever the reference past length being
used is. Uh So, I think this logic might work
(27:30):
if you had like a group of a thousand people walking,
and then you had all of them count their steps,
and then you averaged all of those together. But if
it was just a single person, I would tend to
think that their personal count might be biased more in
one direction or another. They would just tend to have
longer than average or shorter than average steps, and that
(27:51):
even a pretty primitive machine would be better. But I
don't know. That's fascinating, Yeah, I don't. I don't know
what to make it because yeah, I can. I can
see what they're getting at with the idea that some
sort of a basic mechanical flaw in an ancient odometer
device that you would just consistently get the wrong number,
(28:11):
and then that would build up over time, and then yeah,
when when it comes to the actual steps and the
counting of those steps by an individual or individuals, you'd have,
you know, a little, a little in one direction, a
little another direction, but it would sort of even out. Yeah,
that's that's fascinating to think about. I mean, I think
it would be more likely to even out if you
were talking about a group of people, like a large
(28:34):
group of people all average together. Yeah, I don't know
if that'd be the case for a single person anyway,
whether or not they were using mechanical odometers, ancient dematists
did a not at all bad job of measuring different
distances between milestones between cities, and it's possible they were
helped in this task by devices like the ones described
(28:56):
by Vitruvious and Hero. But ultimately, I think we don't
know for sure if they use these devices or not,
and if they did, we don't know for sure who
invented these ancient odometers. It's it's one of those questions.
You know, there are many inventions where we just don't
know where they came from. I wonder too if it
might have been a situation where they use both where
(29:18):
where their specialist in their field. So perhaps, like specialists
in other fields, they're using more than one method and
then comparing the numbers and figuring out some sort of
more accurate measurement based on the two. Yeah, that could be.
I don't know. But anyway, it's really impressive that in
the what it's like the third or fourth century b c.
(29:39):
We've got people getting like really accurate estimates of of
travel distances that are on the order of hundreds of miles. Yeah,
that's fascinating. Now, all of this is going on in
the Greco Roman world, but as we've partially alluded to already,
there's there's also a history of the odometer in Chinese
civilization as well. In particular, the device in question is
(30:04):
the Lee recording drum carriage. Now, this is sometimes attributed
as an invention of Zongheng, who lived at seventy eight
through one c E. This is a Chinese polymath and
court astronomer in the Eastern Han dynasty. Uh. This is
an individual we've talked about before because there are a
(30:25):
number of different inventions that are attributed to him, one
of which was an early form of earthquake detection device. Uh.
He had an important role tending calendars and celestial events,
aiding the Emperor Um, who of course ruled at the
mandate of Heaven, so, you know, maintaining the balance between
cosmos and civil life. And this is a period of
(30:49):
time that sometimes referred to as the Golden Age of
Chinese history, for centuries of economic prosperity, that's all the
traffic of goods and ideas across the Silk Road. He
was an inventor, a poe it in an Early Scientist.
We have an older invention episode about the earthquake detection device.
And I was looking back at some of our notes
and I'm reminded that that you shared some of his
poetry in that episode. Oh I don't remember that now.
(31:13):
Was it good poetry? Oh? Yeah, yeah, that's good stuff. Um.
So he's credited with a number of inventions, innovations, and achievements.
He wrote a treatise on the Mystical Laws of the Cosmos,
which included the theory that the moon did not emit light,
but reflected the light of the sun. And he's also
sometimes attributed as the inventor of the Lee recording drum carriage,
(31:33):
which again is this um uh, this this odometer of
sorts in Chinese history. Now it is worth noting that
that kind of like the situation with Hero and Archimedes,
we have a very famous historical inventor here, and he's
attributed with a number of inventions. And so I guess
the question always lingers, is this an invention that this
(31:55):
individual invented? Is it something that they described it something?
Is it's something that just ends up being attributed to
them because the technology was known during that time, or
it's based on surviving records, etcetera. Yeah, exactly. So I
ended up looking at some of the writings of Joseph
need Him on this. So Needham lived. He was a
(32:19):
British biochemist, historian of science and sinologists who wrote rather
extensively on the history of science and technology in China.
His second wife, lu gives him was a Chinese historian
and biochemist, and she was an important co researcher and
co author in his work. So we're talking multiple volumes
that he wrote during his lifetime, very very much his
(32:42):
life work. So before we get to the carriage itself,
I thought we might stop to just consider Rhodes in
ancient China. So Needham writes about Rhodes in general in
the short Science and Civilization in China, and he points
out that they were quite comparable to the famous roads
(33:02):
of the Romans. Both empires had extensive road systems that
served as a means of logistically connecting their vast land
holdings for travel and trade as well as you know,
playing an important part is just in just communication through
the empire. That's always something to keep in mind, uh,
that the road is also a lane for communication. Now,
(33:24):
both systems, the Roman and the Chinese, fell into long
periods of decay after the third century see he points out,
though he writes that while the collapse of Roman roads
had more of a fracturing effect in China, natural and
artificial waterways and some surviving mountain road systems enabled these
far reaching routes of communication to remain open. He also
(33:46):
points out something very interesting about these two independent systems,
that it's this rather on inspiring and I thought really
nicely written. And it also kind of ties into some
of the stuff we talked about in our previous episode
about the Roman military that the Dethrone Emperor series quote.
Should the Romans have ever succeeded in conquering the Parthians
(34:06):
and the Persians, the two road systems might have met,
perhaps somewhere west of shin Jiang, but this was not
to be. The octopus like arms expanded independently, each in
a world of its own, their builders, troubled only occasionally
by the vaguest rumors of another system too far away
(34:26):
to matter. It's in John, by the way, is in
northwest China. That's where he's talking about here. So, yeah,
this is such a I love this quote because it's
just a imagining these two independent road systems, like like
like octopuses, Uh, each doing their own thing. And if
you know, world history had gone a different way, there
could have been a situation where they met. Uh. It's
(34:49):
it's crazy to think about, like like roads, I've often
thought about. You know, you encounter a road and where
does that road end? You know that basically goes It's
not infinite, but uh, you can it stretches on for
such a great distance. And to imagine these two vast
systems um almost but not quite coming together. Yeah, it's
(35:09):
kind of like I don't know if if you've ever
played around with this to to see like how far
one can drive on a given continent or on connected continents,
Like at what point do things seem to break down
and you would have to find some other route to
connect with another road? And I know when you get
into Eurasia and Africa, like there are some pretty long
(35:29):
travels by road that are that are possible today. The
road is not going to be necessarily to be great
the whole way, but you can do quite a lot
thank so. Anyway, Needham points out that with the odometer
or the way measure, it's it's a pretty simple proposition
(35:51):
from a mechanical standpoint. If you have the wheel already,
and you have row, and you have if you have roads,
you have wheels, then all it is is quote a
system of toothed wheels constituting a reduction gear train so
that one or more pins revolved slowly, releasing catches at
predetermined intervals, and in the case of this invention, striking
(36:12):
drums or gongs, so the lee recording drum carriage. What
is Alie Alie is the traditional Chinese measure of distance today,
standardized at five meters or one thousand sixty feet, but
as with a mile and Western traditions, historically there's some
drift over exactly how far it is supposed to be.
(36:34):
But it's standardized today and would have been standardized under
different rules and different dynasties. Yes, standardization of measures does
seem like such an important part of this too, because
I when I kept thinking about the idea of of
a bimitist potentially trying to measure distance with paces, I'm like,
what is So You've got to have something that's like
(36:55):
a reference pace, right, If you say something is x
number of paces long, you've got to either know how
much your pace typically relates to a standard measure like
a mile, or you've got to be using your paces
as some kind of literal standard measure, like people would
know what that number meant. Yeah, yeah, it's yeah. The
(37:17):
the history of of measurements alone would be something interesting
to come back to, because, of course you get into
use of various parts of the human body uh to
to form your base measurements, UH, the creation of tools
and UH and certainly when you're getting into weights for
goods and trade, like some of our oldest data and
oldest examples are all related to that. But then when
you start thinking about these larger measurements, like the measurement
(37:40):
between you know, the fourth in the frontier, that sort
of thing, like you like, you can't just count, You
can't just have someone go out there with essentially a
ruler and say all right, start measuring it off, like
you've gotta have some other system. Yeah, yeah, alright, So
Needa gets more into into the subject of the lea
the Lee measuring art here in Science and Civilization in China,
(38:02):
Volume for Physics and Physical Technology, Part two, Mechanical Engineering, Um,
and yeah, it gets into the nature and origins of
the Lee recording drum carriage. He cites several sources and
post in some of these resources that go into more detail.
Others just kind of mentioned it in passing and points
out that that many of the mentions of the carriage, yeah,
(38:23):
they don't actually describe the mechanism employed. In at least
one case, it shows up as a math problem. It's
it's something along the lines of if the Lee recording
drum carriage were to travel between this city and this city,
how many times would the gong u sound that sort
of thing. The concept seems to date back to the
Hun dynasty, and this is where the attribution to zong
(38:44):
Hang seems to come into play. But when the carriage
is described, it's generally described as a carriage drawn by
four horses, and it works based on multiple cogged wheels,
some vertical and some horizontal, you know, all of course,
much like the earlier example in the Greco Roman traditions
we were discussing, you know, it's tied to the movement
(39:04):
of the wheels. In the simpler version of this um
of this carriage, it's said that there is a wooden
man in the carriage who is mechanically made to strike
a drum with the passage of each lee. So the
wheels are turning, the cogs are turning, there's a mechanical
wooden man inside who like like a music box, he
(39:27):
is going to mechanically strike a drum in this case,
every time one lee has passed. Beat that vitruvious. You
did not have a wooden man, did you. Later, a
more complex version is described as being two stories in heights,
So so it's a carriage that has two stories and
each story has its own wooden figure. The lower figure
(39:50):
strikes a drum every lee, while the higher figure rings
a bell every ten le Okay, So one difference that
occurs to me here is this would still if it's
keeping track of the distance in an accurate way, but
doing so by making a sound instead of by say,
accumulating uh, pebbles or beads in a container. It's something
(40:14):
that you would to some extent need to continuously keep
track of as you're traveling, Like it would still require
effortful engagement of the memory by somebody doing the traveling, right,
That's right. That's based on my reading here of need him.
I don't think there's any indication that it was spitting
out like you know, balls or or or or pebbles
(40:36):
that could then be counted later, or there was anyway
recording how many leaves it passed. It was just a
you know, a ringing of a bell or the striking
of a drum based on the intervals traveled, which would
still be useful, but would require more work than or
at least work spread out over a longer period of time,
rather than say like a single counting activity in between
(40:59):
travel segments. And in this we get into one of
the big questions about the Lee recording drum carriage, and
that is was this a device that was at all
originally intended to measure distances? Or was it you? Or
was it more about music? Was it more about novelty?
(41:19):
Was it was it? Why was the technology employed? So
again this was this? These writings are typically revolving around
the Han period or perhaps a little earlier, but the
Lee measuring drum carriage was not known as such until later,
and need Him discusses that this might mean that the
invention was in fact more expressly for musical performance rather
(41:39):
than the measurement of distances. Again, at least during this
time period. It may have may have changed later when
someone realized, oh yeah, we can just count how many
strikes of the drum, we can count how many rings
of the bell, and then that's data that could prove useful.
But he stresses that you know, these are still interconnected,
interconnected possibilities, um. And if you're if you're asking, well,
(42:01):
why would they do that, like why build a carriage
like this? And why does it remain something other than
just like a one time novelty, Like why is it
written about so much? And he points out that music,
of course, is often part of a procession, and he
stresses that quote carriages for musicians, whether mechanized or not,
survived in imperial processions through many subsequent dynasties. So the
(42:24):
idea here is that the mechanical version uh here develops
from non mechanical carriages with human musicians inside them. Imperial
fleets of vehicles, as he refers to them, would have
likely included palace officials and so forth, but also entertainers musicians.
So as everyone's traveling down the road, there's music, and
(42:47):
at some point someone says, hey, what we could We
could build some gears. We could make a mechanical musical
man inside one of the carriages, putting those flesh musicians
out of the job. Well, I don't know if they've
become cletely out of the job, because you know that
these these mechanical musicians can only do so much here.
But but yeah, for for a modern comparison, we might
(43:07):
think of of a parade float as a as a
counterpart is something like this. It does sound a lot
like a parade float. It would have been, according to
one account, painted red and decorated with flowers, and birds it.
It's described as being escorted by eighteen men. Uh, and
there would have been a phoenix headed carriage pole on it.
So this was not clearly not something that was like
(43:29):
a Google Maps vehicle that was out there just to
perform a task. It Also it said that it looked marvelous.
It's a joyous vehicle. And once more, Needham stresses that
we don't know for sure if it was ever used
by cartographers. Uh. It's possible that that later on photographers
may make use of the data that could be provided
(43:50):
by this, but we're not sure. Interesting, so Needham points
out that heroes description of the podometer did not claim
it as a new invention. He mentions the truvious and
then mentions that after hero Vitruvius, the odometer appears in
Western Europe during the fifteenth century, so it's it's kind
of not really on the Western European radar for a
(44:10):
long period of time, or doesn't seem to be based
on surviving histories, and then it re emerges. Quote. The
pattern is therefore the same as that which we have
repeatedly met with i e. Greek antecedents paralleled or followed
by followed at short distance by Chinese developments which continue
throughout the medieval period, and then a reawakening of the
(44:32):
subject in Europe. So in this he's touching on something
that was kind of a career spanning question for him.
Is often referred to as the need Him question, and
that the question is basically why didn't China beat Europe
to the scientific revolution. He's been a fair amount of
his work thinking over this and looking to answers and
Chinese social institutions and more. Uh though, as as of reading,
(44:55):
the psychologist Nathan Siven, who would have been I think
at times of liberator with Needham, pointed out that, you know,
the whole thing is basically a why did an X happen?
In history question, which by some estimates is less than
a fruitful enterprise. You know, you get into all sorts
of complex butterfly wing flapping concerns when you start asking
(45:16):
questions like that. They can be kind of nifty head scratchers,
but perhaps they are not the best exercise for an historian.
But at any rate, the Needham question, you see it
mentioned a lot in discussions of of the history of
Chinese science. Now, I do want to note in reading
about all this I also read as some material for
(45:37):
needum about another interesting wheeled vehicle in Chinese history, and
that is the south pointing chariot. But that's one we're
gonna have to come back to. But yeah, the idea
of a chariot with another mechanical man on it, but
this mechanical man always points south omous. Okay. So we're
not gonna We're not gonna go through the exhaustive history
(45:59):
of the of the odometer in in recent centuries, but
I thought it might be useful to point out a
few different later innovations that kind of bring us up
to the modern odometer. Um, there's Pascal's calculator. This would
have been an invention or an innovation by Blaze Pascal. Uh.
This was five not an adometer per se, But it
(46:22):
was a computation mechanism that entailed rotating toothed gears, and
much like a modern odometer, one complete cycle of one
gear caused the movement of the next gear. Okay, So
this would have been taking the same principle by which
the ancient odometer worked, but applying it to general calculation
rather than just the movement of a vehicle wheel. Right now,
(46:44):
in the late sixteen early seventeen hundreds, we also see
Thomas Savory's nautical odometer. Uh. Savories most famous invention was
the steam engine, but he also devised a nautical adometer.
I actually couldn't find out much about this, so I
don't know. I'm gonna have to come back to this
one in a few sure, but because I was curious
on how exactly it would have functioned. Interesting. Yeah, supposedly
(47:05):
there was a patent, so it seems like I should
be able to find that patent somewhere. So I don't know,
I have to come back to that one. But this
is a fun part because our old friend Ben Franklin
also enters the fray here when it comes to the odometer.
He's come up in more than one invention conversation, I believe.
So what what was his take? So? In seventy five
(47:27):
he was serving as Postmaster General for the British. Previously
he had been postmaster of Philadelphia, and he wanted more
data on the shortest routes for mail delivery. So he
basically devised a simple odometer to attach to his own carriage.
And UH, and this will for this reason you'll sometimes
see especially some online sources saying Ben Franklin invented the odometer. No,
(47:52):
it's not accurate in the least to say Ben Franklin
invented the odometer. You could say he invented on odometer.
He certainly would one up on the fly here. It
seems so every four revolutions it would register a mile
and the results were apparently pretty accurate based on what
I was reading here. So at any rate, he was
able to to to use the data, uh, to figure
(48:14):
out which route was best for male delivery. Now, one
thing I know I saw reference to on the internet
and I didn't know what to make of this was
the idea of a Mormon odometer. Yeah, this was one that, Yeah,
that came up for me as well. The rhodometer from
Clayton and Pratt. Uh. This would have been eighteen forty seven.
(48:34):
They were pioneers of the Church of Jesus Christ of
Latter day Saints and they apparently crafted a simple odometer
to measure how far a wagon train had traveled. Um.
So that's it's interesting again. It's we're getting into this
area where it sounds like people would find themselves in
situations where they could really use an odometer, and since
the knowledge was was known, you could create one. You
(48:57):
couldn't go to the store and buy one, but the
principles route there. The principles were part of of of
of the technological canon, so you could draw on that
and make yourself a functional odometer. In e Curtis age
Vter came up with a bicycle mounted odometer, the cyclometer,
and then in three we have the Warner autometer, which
(49:20):
I think, like the advertised versions of this, this was
like an actual product. It was a combined odometer, spedometer,
and clock, but it made use of magnetism as opposed
to just pure gear work. Uh So, like those are
some of the big more big innovations in the odometer
in recent centuries. And uh yeah, today the odometer again
(49:41):
is something we tend to just take for granted or
we don't even read it. It just sort of clicks
by there and maybe we check in on it every
you know. However, many thousands of miles, I guess at
vary some people were probably more more into keeping a
close eye in their odometer, or you have to for
work obviously. I think about seeing those surveyors who have
the wheel they use the surveyors the surveyor's wheel. Of course,
(50:03):
I didn't think about that. That that's an obvious um
innovation to compare to some of these discussions of the odometer,
like harnessing the power of the wheel from measurement. All right, well,
we're gonna go and close it out here, but we'd
love to hear from everyone out there. Perhaps you have
particular thoughts about the odometer. It's ancient history, it's recent history,
or or you know, our modern use of the technology
(50:26):
right in we would love to hear from you. As
a reminder, our core episodes of Stuff to Blow Your
Mind publish on Tuesdays and Thursdays, and the Stuff to
Blow Your Mind podcast feed on Monday's we do listener mail,
on Wednesday's we do a short form artifact or monster fact,
and on Friday's we do Weird How Cinema. That's our
time to set aside most serious concerns and just talk
about the strange film huge thanks to our excellent audio
(50:47):
producer Seth Nicholas Johnson. If you would like to get
in touch with us with feedback on this episode or
any other, to suggest a topic for the future, or
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at Stuff to Blow Your Mind dot com. Stuff to
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