Britain once forgot how long an inch is
In 1834, Parliament burned down, and the Standards of Measurement were melted or destroyed. So when there’s no agreed-upon standard for length: how do you fix it? Also: how you can still publicly check the length of your sandwich.
Filmed safely: https://www.tomscott.com/safe/
There’s a correction to this video: the fraction on screen at 00:49 should be 1/299792458. Looks like I copied and pasted an extra 1 and didn’t realise it. Apologies. You can see all the corrections for this channel at https://www.tomscott.com/corrections/
Story research by Jess Jewell
SOURCES:
Report of the Commissioners Appointed to Consider the Steps to Be Taken for Restoration of the Standards of Weight and Measure, 1841, https://books.google.co.uk/books?id=4xVSAAAAcAAJ
A Collection of the General Public Statutes, 1855, https://books.google.co.uk/books?id=UDCaqwCgBKcC
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@TomScottGo
September 5, 2025 at 10:57 am
There's a correction to this video: the fraction on screen at 00:49 should be 1/299792458. Looks like I copied and pasted an extra 1 and didn't realise it. Apologies. You can see all the corrections for this channel at https://www.tomscott.com/corrections/
@justacommenter9389
September 5, 2025 at 10:57 am
0:38 ive visited NIST to check out their massive radios, very cool!
@svihl666
September 5, 2025 at 10:57 am
What the helly
@-xLucas
September 5, 2025 at 10:57 am
oops
@silvergolddjingga
September 5, 2025 at 10:57 am
jadi jaraknya include "knob" yang di sample itu atau bagian dalam nya aja ? 😛
@defiik
September 5, 2025 at 10:57 am
you can always just reference the centimeter
@johncarr8557
September 5, 2025 at 10:57 am
Fascinating historical curiosities, whilst being completely clear that: What's the good of Mercator's North Poles and Equators, Tropics, Zones, and Meridian Lines?" So the Bellman would cry: and the crew would reply "They are merely conventional signs!
@greegerm1073
September 5, 2025 at 10:57 am
I semantically disagree. Their definition of a "foot" was defined as that specific length for each district. Definition change, and many definitions/meanings of words are interpreted differently in many cases, or specific and different in many cases. Like football, american and normal.
@ddunfuh9239
September 5, 2025 at 10:57 am
I could measure 1 inch easily with nothing but my body
@fransnagel
September 5, 2025 at 10:57 am
the basis of the metric system is that 10cmx10cmx10 cm is one liter and one liter of water weighs 1 Kg=1000 grams.
@RandomerFellow
September 5, 2025 at 10:57 am
The best thing would be for the whole world to forget how long an inch is. For good.
@WorldLie
September 5, 2025 at 10:57 am
I could have helped, it's exactly my size.
@CorbiniteVids
September 5, 2025 at 10:57 am
Was it all in frame? Impressively so, right up to the edges but no further
@SimulatedGoat
September 5, 2025 at 10:57 am
They could've just visited asia
@Poorexampeofhuman
September 5, 2025 at 10:57 am
What is the natural decay of the element alter the length weight and dimensions of said measurement device. I mean if you take something that weighs 1 kilo and you know let it sit for 200 years is it going to weigh the exact same amount that it did 200 years before?
No it won't because of the natural decay of elements. So how do we come up with a definitive exact measurement for a given distance or way a given length of time. We've got to come up with a constant that doesn't rely on physical matter
@deafeningoctopus
September 5, 2025 at 10:57 am
That footlong sandwich was actually surprisingly accurate in length
@urnewboy1
September 5, 2025 at 10:57 am
I mean does it matter when you measure things with randomly made up measurements that make 0 sense? 😂 countries that use imperial system don’t seem to care about being precise. Stones, feet. Why not logs, bags of sand or cats for length?
@Kokin0
September 5, 2025 at 10:57 am
6 inches is a spectrum
@SoapySupreme
September 5, 2025 at 10:57 am
“You don’t need to calibrate anymore this is the truth” now that just makes no sense. The final machine would be calibrated and then could calibrate the next machine. It shows the last machine what the calibration is.
@amehak1922
September 5, 2025 at 10:57 am
The length of an inch would change during the medieval era with every king. It was based on the length of the kings half thumb, and a foot by their feet. They became one set length centuries later.
@stephenwilliams163
September 5, 2025 at 10:57 am
Accurate units of measurement are important to Todd so that he can plan how much fuel he'll need to travel anywhere with his jetpack
@davidkachel
September 5, 2025 at 10:57 am
This would explain some of the outlandish claims made by British men in bars, when talking to British women!!
@bud-yo
September 5, 2025 at 10:57 am
Imagine forgetting something so essential
@Andrew-du6jh
September 5, 2025 at 10:57 am
2025 anyone?
@planktonfun
September 5, 2025 at 10:57 am
nowadays Britain forgot what democracy is
@shaundenehy4681
September 5, 2025 at 10:57 am
Well the only flaw is we only measure the speed of light two ways, there and back, So we're assuming it travels out of constant rate and physics is always changing in the universities expanding faster than the speed of light.
@PaulSteMarie
September 5, 2025 at 10:57 am
The definition of the foot in meters happened all the way back in 1863, long before the meter was defined in terms of the speed of light (more precisely in terms of the wavelength of a particular spectral line of cesium).
The international foot was introduced in 1959, but it just changed the ratio to make conversion from inches to meters easier. (100/3739 vs 254/10000).
@hiimemily
September 5, 2025 at 10:57 am
Most of the men I know still don't know what an inch is.
@anoncomposmentis
September 5, 2025 at 10:57 am
I really enjoyed that. Concise and engaging
@kevincozens6837
September 5, 2025 at 10:57 am
Standards are built upon standards. That publically accessible standard shown at the 4 minute mark provides a standard measure but only at a particular temperature. That requires another standard to be set so you know when you are at the correct temperature before checking the length of the standard used to measure distance.
@Nick-xf5hr
September 5, 2025 at 10:57 am
Americans would never have landed on the moon using feet and inches. Metric makes life and mathematics easier
@johnmorkunas6707
September 5, 2025 at 10:57 am
When did they change the meter? It was originally a certain fraction of a meridian. 🤓
@baltulielkungsgunarsmiezis9714
September 5, 2025 at 10:57 am
Imagine if this had prompted the UK to adopt SI units, so much confusion for the next 200 years would have been spared.
@wrsmith711
September 5, 2025 at 10:57 am
a meter was originally defined as 1/10,000,000th of the distance from the Equator to the North Pole.
Comments are closed.