Units of Measure index

Foreign units

index --- alpha --- intro --- length --- area --- volume --- weight --- money --- angles --- weather --- other --- foreign --- trades --- documents --- metric --- tables

Imperial units were used in Great Britain. Some are still legally used, and the rest are used informally. Similar units have been used in other countries.

United States of America
Units of volume "A pint's a pound the world round"
Measuring cups Barrels
Drinks measures Builder's tape measures
Difference between yards Military Pace and Tierce
Board foot Acre-foot
Penny nails Strange measurements
Gun gauges Old cake recipe
US Survey Foot Other units
Paper sizes on the trades page
Australia and New ZealandHow to order beer in Australia
Super foot
Chile and Argentineanthumbs
France and elsewherethumbs, pounds, feet
France and Irelandagricultural unit of volume
Spain and Portugalweight
Channel Islandsmeasure of land
South Africamoney, weight

United States of America

The U.S. Customary systems are mostly the same as Imperial units, so see length, area and weight pages for details. However, the volume units are different. They share the same names, but have different values. Click here for the Imperial units of volume.

This is a quick convertor which gives an answer rounded to 2 decimal places.

Enter value:   =   ?  

The main difference, which seems very strange to the British, is that Americans have different units for liquid and dry. Now, certain Imperial units, such as bushel, were used for dry goods, such as corn, while a firkin is a cask of beer. Still, if you buy an Imperial pint, it will be the same size, whether it is beer or shrimps! In America, there is a dry pint and a liquid pint.

The value of the Imperial volume units are different from the U.S. ones but the proportions are the same except for the fluid ounce. The American system has 16 fluid ounces to the pint (similar to weight) but the Imperial system has 20 fluid ounces to the pint. Also, the U.S. spelling of the metric unit of volume is 'liter' and the British is 'litre' (similar to the U.S. spelling 'meter' and the British 'metre'). For the history of all these units, click on the Imperial links.

NameU.S. dry unitU.S. liquid unitImperial unitTableSee
- - 29.57 ml1.8 cu inch28.41 ml1.73 cu inch4 fluid ounces = 1 gill
16 fluid ounces = 1 pint
5 fluid ounces = 1 gill
20 fluid ounces = 1 pint
gill - - 118.29 ml7.22 cu inch142.07 ml8.67 cu inch4 fluid ounces = 1 gill
4 gills = 1 pint
5 fluid ounces = 1 gill
4 gills = 1 pint
cup - - 236.59 ml14.44 cu inch284.13 ml17.34 cu inch8 fluid ounces = 1 cup
2 gills = 1 cup
2 cups = 1 pint
10 fluid ounces = 1 cup
2 gills = 1 cup
2 cups = 1 pint
pint550.61 ml33.6 cu inch473.18 ml28.88 cu inch568.26 ml34.68 cu inch16 fluid ounces = 1 pint
2 pints = 1 quart
8 pints = 1 gallon
20 fluid ounces = 1 pint
2 pints = 1 quart
8 pints = 1 gallon
quart1.1 liters67.2 cu inch0.95 liters57.75 cu inch1.14 litres69.35 cu inch2 pints = 1 quart
4 quarts = 1 gallon
gallon4.4 liters268.8 cu inch3.79 liters231 cu inch4.55 litres277.42 cu inch8 pints = 1 gallon
4 quarts = 1 gallon
2 gallons = 1 peck
peck8.81 liters0.31 cu feet - - 9.09 litres0.32 cu feet2 gallons = 1 peck
4 pecks = 1 bushel
bushel35.24 liters1.24 cu feet - - 36.37 litres1.28 cu feet8 gallons = 1 bushel
4 pecks = 1 bushel

I am not sure whether the U.S. units that I have missed out, above, exist or not (such as the dry fluid ounce). The liquid U.S. units are 86% of the dry U.S. units with the same name. They are both smaller than the British units, apart from the fluid ounce which is bigger. The U.S. wet pint/gallon is 83% of the British pint/gallon, and the U.S. dry unit is 97% of the British pint/gallon. So if someone from the UK buys a gallon of gas (which we call petrol) in the United States, he will only get 83% of what he thinks he will get. While an American will probably flood the forecourt of the British filling station! One interesting facts is that an American dry pint is close to a British pint, whereas an American wet ounce is close to a British fluid ounce.

American cup measures
American cup measures - 1, 1/2, 1/3, 1/4 cups

Early in the 1800s Congress standardized on a wet gallon of exactly 231 cubic inches and a bushel of exactly 2150.42 cubic inches. The Imperial units of volume are based on the fluid ounce, which weighs exactly 1 ounce under certain temperature and pressure conditions. This is interesting, as it mirrors the different styles of measuring cooking ingredients. The Americans use volume measures, in particular, cups. The British sometimes use volume measures for liquids, such as fluid ounces and pint for large amounts and spoons for small ones, but mostly we use weights, pounds and ounces. Any serious British home cook has a set of scales. Now, I realise that a measuring cup is cheaper than scales, but I would have thought that it is less reliable. You need to get the top level, and it matters how much you shake it down. I am also worried about butter. You can't measure butter in a cup unless you melt it. I have been informed by a lot of correspondents that the cups are marked on the packet. Well, ounces are sometimes marked on a British packet, but we don't use them! We weigh the butter ourselves. What if you've already opened the pack to spread on your toast? And if you visit somewhere which doesn't mark butter, you won't be able to cook, while we can go to America with our scales and manage quite OK!

Another correspondent explains how you can measure hard fat such as butter or lard using a volume measure. You half-fill a (large) measuring cup with (cold) water to a given amount, which you note. Then you add the fat to the water. The water level will naturally rise to a new level. The difference between the levels gives the volume of the fat. I have a few comments about this. The measure must be big enough for fat plus enough water to cover the fat. You must use cold water or the fat will melt, which will still give you the right amount but leave you with the problem of separating it out! I was also worried that the fat would float, which means the idea wouldn't work. In fact, it does float but only just, so this may not matter. Finally, the fat will end up wet, and this might matter for certain recipes. I can imagine trying to pat the water off the fat - certainly possible but a little awkward.

I had another query, which was this. If there are dry units of volume and wet units of volume in America, and since Americans measure their cooking ingredients in cups, and some ingredients are liquid and some are dry, are there different measuring cups? And if there are, what measures what? How liquid does it have to be? There is cream which is almost solid, for example. This provoked quite a correspondence which I enjoyed immensely (some Americans are apparently unaware that there are different liquid and dry measures in their own country!) but eventually the conclusion was that all cooking measures use liquid units. It doesn't matter whether you are measuring milk or flour, the amount is the same. There are different liquid measures and dry measures, but these are for convenience of use. They both are marked in liquid units of volume. One correspondent said "Dry measure is actually little used in the U.S. A cup of flour or a cup of milk in a recipe are measured in the same measuring cup. Unless specified otherwise, all measurements are struck even with the top of the container. The only survival of the identically named and slight differently sized dry units is that they are the officially sanctioned units for the purchase of fresh fruit, like buying a pint of strawberries. Most people are completely unaware that a pint of blueberries isn't the same pint as a pint of milk." (In Britain, we sometimes buy shrimps and prawns by the pint, and we use the 'wet' measure. In fact, the seller might even used a beer glass to measure them!)

The cup measures above (which I bought in a charity shop in Britain) has a cup measuring about 8 British fluid ounces. That would make it an American wet cup.

Another correspondent has made a point about shaking ingredients down: "Some ingredients will differ in weight if loose or packed, so a recipe will further specify if the ingredient is to be packed or loose. When not specified the usage is to pour the ingredient into the measure until the desired level is reached. Sometimes a note tells the cook not to shake or pack, but this is considered unnecessary. Nuts can be whole, broken, ground etc. Each form will have a different weight for a given measure, but for the purposes of a recipe that is irrelevant. " (I disagree with him there. I think the weight of nuts matter more than their volume.)

A British TV programme called QI suggested that the American method of weighing was superior, since you didn't actually need a specific weighing cup. Since all recipes were marked by volume, you used any cup you had, and the proportions would still be true. This means that any cook, however ill-equiped, could use the recipe. I'm afraid that I don't agree with this. Many recipes use items such as eggs which will throw the proportions out. Also, cooking times vary for different volumes - a larger cake takes longer to bake. And if you use whole cups (since an arbitrary cup won't have markings for half a cup, etc.) you will end up with large amounts.

I am still bemused at this resistance to buying scales. They are not that expensive, considering the cost of a cooker, or a decent saucepan, or even a good knife. They don't take up that much room. They are easy to use. They are accurate. They can be used to measure anything. The only arguement against them is if your recipes don't use weights.

Still, I would like to thank all my correspondents for illuminating me on this important subject, even if you confused me horribly en route!

American measures
A diagram showing relationships between different US customary units of volume. Not known whether these are wet or dry units.

An email from Texas, said:
"We still sell berries by the pint in this country, but potatoes are sold by the pound. Potatoes used to be sold by the peck."
In Britain, we still sometimes buy prawns and shrimps by the pint, but I've not heard of fruit being sold that way. Strawberries are sold by the punnet (a small cardboard basket), but the punnet is usually weighed to give the price. Potatoes were sold by the pound, or stone if you bought enough. Now it's all kilos, of course.

A correspondent says "Measuring in this manner (by volume) has an ancient history. In Ali Baba & the Forty Thieves a volume (wet) measure was used to count gold coins :)" I'd prefer to weigh gold coins rather than measuring them by volume! The correspondent who uses water to measure the volume of fat (see above) points out that the method can also be used to (accurately) measure gold coins. Quite true. Archimedes used this method to work out the volume of a gold crown, to check if it was made of pure gold or not (since weighing it was easy, and what he needed was the specific gravity, which is heavier for gold). It was discovering this, rather than his famous Principle, which caused Archimedes to jump out of his bath shouting "Eureka!" which means "I have discovered it!"

While we're talking about cooking, oven temperatures are on this website here.

A pint's a pound, the world around

Another correspondent quoted a saying that he learned as a kid, "A pint a pound, the world around." This is not true. It is true to say that 1 ml of water is 1 gram, because it's defined as so. A pound is 454 grams. An American liquid pint of water is 471 grams, which is approximately the same. A British pint of water is 567 grams, which is definitely more. But this is only talking about water. Since the same amount of different materials will weigh different amounts, this can only be regarded as an extremely approximate conversion. Here is a table in a British cookery book of mine for converting American cups to British ounces, which is converting a volume unit to a weight one:

Different weights of contents of American cup
in oz
Butter, lard8
Cheese, grated4
Breadcrumbs2 1/2
Sugar, brown (packed down)6
Sugar, granulated7
Sugar, caster6
Sugar, icing41/2

This is a big spread of amounts! You can see that getting weight and volume muddled up is not a good idea. But the saying seems to be encouraging this. By the way, there are several different grades of sugar in Britain, with icing sugar being the finest and granulated the most coarse.

Another correspondent says "The saying 'A pint's a pound, the world around' is a mnemonic to help remember the number of ounces in a pint. That is, there are the same number of liquid ounces in a pint as there are (weight) ounces in a pound -- i.e. 16. It is not about the weight of a pint of anything. I suppose people found it easier to remember ounces in a pound." However, it doesn't explain why it's "the world round" since the British pint has 20 fluid ounces. Also it's not a very good mnemonic, since it seems that people misunderstand it. It turns out that an American dry pint is close to a British pint, while an American fluid ounce is close to the British fluid ounce fluid oz. I don't know if this has any historical significance in the origins of the units.

Another correspondent from Australia says "When my mother taught me to cook, she used, as a rough rule of thumb, one pound of sugar to one pint of vinegar when making chutneys, relishes, pickles and ketchups; and when making jam, one pound of sugar to one pint of cooked fruit." That seems very sensible! Perhaps that's the origin of the saying, but it still worries me that there are three different explanations!

American measuring cups

A correspondent describes an old measuring cup, "The Silver Measuring Glass" manufactured in Brooklyn (NY). Unfortunately, no-one seems to know how old this cup is.

Marked on the cup, at the following equivalent levels are:

4oz ("liquid weight") = 1 "T" Cup
= 2oz (dry weight, i.e. "sifted flour")
= 1 GILL
2 "T" Cups = 1 Coffee Cup
= 8oz
= 1/2 pint (2 Gills)
= 1/4 lb (dry weight).

Written on the side are also helpful equivalents:


The weight/volume equivalence is interesting. There is a cake still sold in America called a Pound cake. This was (and perhaps still is) made of a pound each of sugar, butter, flour and eggs. It suggests that American cooks haven't always used cups! Does this measuring device describe a time when recipes went over to volume measurement rather than weight? The British are in the process of converting from Imperial to metric and so our cooking books often have imperial/metric conversion tables, and our measuring jugs and scales also have both. But at least we are not shifting from weight to volume. In this cup, you can see that a pound of butter and sugar are said to be a pint. However, there is a peculiarity about the flour measure. It says 4oz ("liquid weight") = 2oz (dry weight, i.e. "sifted flour"). Now, this is nonsense. 4oz (weight) cannot be the same as 2oz (weight), whatever you're measuring! But if you look at a modern British table converting between American cups and weight, you will see that a cup (half pint or 8 liquid oz) of flour weighs 4 oz. So the "liquid weight" is not a weight, but a volume (half a cup).

One American reference work said "Measures are classified as either dry measures or fluid measures. Fluid measures are measures of volume, while dry measures are measures of weight. Whether the ingredient you are measuring is dry or fluid really doesn't matter, and will only confuse you. Simply use the measure that is specified in your recipe." However, it then went on to give a recipe which just mentioned 'ounce' without saying whether it was weight or volume! What's more, this means that an American dry ounce is a weight, a liquid ounce is a volume, and both the liquid and dry pints are volumes (but different amounts). Help! A correspondent has told me that the only place that she's ever seen (weight) ounces being used is to weigh babies, which may explain why this confusion doesn't cause trouble. However, to Americans coming to Britain or using British measures, in Britain there is a single pint and gallon, used for both wet and dry measures. We always say 'fluid ounce' if we measure volume, and ounce always means weight. But we are now mostly using metric measures for volume and weight (which are even better defined). However, our recipe books often have a glorious mixture of both metric and Imperial, even within the same recipe, sometimes!

I wondered if a "T" cup was a teacup. Another correspondent has the same measuring cup. He says "In reference to a 't' cup being 4 ounces, it is known in antique cookbook circles that a modern teacup is not the same measure, the change happening sometime around 1900."

Another correspondent's measuring pitcher:

It is glass. It has a handle for pouring and the spout is rounded.
On the side written from the bottom to the top dividing the measurements into 4 sections--it says:

On the top of one section it says 1 QUART EVEN FULL. Underneath it and up the side there are 5 lines shown
1/2 PINT
On the other side it says at the top it says LIQUID WEIGHTS (the lines do not correspond with any of the lines on the liquid side).
4 OZ
8 OZ
12 OZ
20 OZ
24 OZ
On the other side at the top it says 8 "T" CUPS OR 4 COFFEE CUPS EVEN FULL. Underneath it and up the side it measures
3 "T" CUPS
5 "T" CUPS
On the other side at the top it says POUND FLOUR SIFTED EVEN FULL. Underneath it and up the side it measures
2 OZ
6 OZ
10 OZ
measuring pitcher

Note the "T" cup again. Again, you can see the distinction between liquid weights and flour. Here it's good milk which contains 10% cream rather than cool milk. The statement that a pound of sugar (or butter) being a pound may have led to the (incorrect) saying that a pint is a pound (no, it isn't!)

U.S. barrels

I found this in an encyclopedia:
Most fruits, vegetables, and other dry commodities - 7,056 cubic inches
Except for cranberry barrels which are - 5,826 cubic inches
Wine barrel - 31.5 gallons
Ale and beer barrel - 36 gallons
Proof spirits barrel - 40 gallons
Calculation of federal taxes on fermented liquors - 31 gallons
Petroleum barrel - 42 gallons
Fish, beef, and pork barrel - 200 pounds
Cement barrel - 376 pounds
among others ...

A correspondent has added that beer and whisky barrels in the U.S. are 31 gallons. I find that table to be a wonderful confusion of units, and wonder why the cranberry growers had their own barrel. It does mean that I know exactly what 'pork barrel politics' is based on.

The beer barrel in Britain is 36 Imperial gallons and a herring barrel was 26 2/3 Imperial gallons.

Drinks measures

A correspondent told me about "shots, ponies and jiggers, which appear to be American measures used most often in bartending. A shot of whiskey will get you one fluid ounce (US). A pony is also 1 US fluid ounce. A jigger is 1.5 fluid ounces (US)."
Brewer's Phrase and Fable (a well-known British reference book) says that in America, a pony is a small beer-glass holding slightly under a gill (a quarter of a pint) - so the amount is different. The Australian pony is exactly an Imperial gill. I associate drinking shots with American films, but I think that jigger is used for recipes for cocktails. In Britain, a jigger is more likely to be a standard spirit measure, although when making cocktails, you can have a relative measure rather than an absolute one, since it is the proportions that matter rather than the quantities.

Another correspondent told me about alcoholic beverages, specifically spirits, sold by the 'fifth'. This was a fifth of a U.S. liquid gallon or 757.08 ml. It's now been replaced by 750 ml but still called a 'fifth'.

Another correspondent says "I figured it could help you if people wrote in about measures in their region. Here (Utah) we have some strange rules for drinks. For example, a mixed drink cannot contain more than two ounces of liquor... Some clubs (to serve liquor, the establishment was until recently required to be a private club for which you could buy membership 'by the night' or annually) have been known to overlook this, but that's the law. It's not uncommon to drink 'shots' and a 'shot' glass will contain up to a jigger of fluid. When one says jigger here, it is most often in reference to the measurement tool having a one-ounce 'cup' stuck by its bottom to the bottom of a half ounce 'cup' so that only one of them may contain liquid at a time. While it's true that a jigger is used to measure for mixed drinks, it is rarely actually used by experience bartenders. Many bartenders count at a comfortable rate while pouring liquid at a roughly predictable or familiar rate. And some just eyeball or 'feel' it. At any rate, shots are common. And often 'taking shots' means informally to swill a small amount of liquor, but may mean an ounce, a jigger, a double (two ounces), or some other volume that will go down in one swallow... But it's recognized that when you ask for a vodka or what-have-you that you'll get roughly an ounce and a quarter if you don't specify anything else. Samples of beer (yay free!) are given in rocks glasses (lowball or old-fashioned glass, maybe 7 oz). Beer is served by the bottle (different amounts depend on which beer, but domestic standard is 12 oz), the pint (16, a 20 oz mug in some taverns), the 'big dog' (a local measure, 32 oz), the pitcher (2 - 3 liters, meant for pouring but some people drink from them as if they were a mug), and in brewpubs you can buy beer by the growler (1/2 gallon container you purchase separate from the beer, filled from the tap). Of course, at the grocery store you can buy 40s and 12s and cans. But all beer sold outside of a state agency for off-premise consumption is required to have a lower alcohol content, 3.2% or lower. In some clubs, the bartenders still recognize the 'finger' as a unit of measure. Sort of... 'two fingers' used to mean that liquid was poured into a glass until it reached the top of two fingers held horizontally against the glass, now it's often recognized as a double."

Builder's tape measures

A correspondent wrote: "when u look on any tape measure every 16inches has a mark and nowhere says wot this mark means, please say if u no cos so many mates of mine are trying to work it out."
Another correspondent wrote: "The tape measures with marks at 16" intervals.... I have seen them used for drywalling (plasterboards, partitions etc) in America etc...that is where an 8'x4' sheet is divided for fixing..i.e. every 16" for battons, hope this helps. More of a chippies tape you might say."
Another suggestion: "The marks are put there to make it easy to set out rafters joists etc. Most board material came in increments of 4 feet ie. 8ft by 4ft plywood sheet. a joist every 16" would mean 4 supports for each board, allowing for joins.
Another suggestion: "Joists in America come at two foot intervals, and 16 inches is the typical spacing for wall studs used in wood-frame construction."
Another suggestion: "I agree with the suggestion that 16 inches is for drywall work. In England the standard distance between uprights in a stud wall was 16 inches. Also floor joists were usually at 16 inches if the had to carry ex 1 inch boards."
So an American or British builders' tape. I've not seen measuring tapes like this in Britain, so I've put this discussion under America.

Another correspondent: "I have a tape measure, that I bought at a car boot sale, it's new looking, plastic and metal. It has marks on the imperial side for 12", which is a foot, 16", which I use for stud walls for 16"centres, but the one that is puzzling me is the one at 19" 7/32nds, that is nineteen inches and seven thirty seconds, I believe it is one fifth of eight foot, but I have never come across anybody who uses this measurement."
Someone sent me the answer, which was on an American DIY website (but the relevant page has disappeared): "The black diamond on the top scale starting at 19.2 inches is for truss layouts for 8-foot sheet goods - also referred to as the 'black truss' markings. If you divide five into 96 inches (8 feet), it will give 19.2 inches - in other words, 5 trusses per sheet."

Difference between yards

During the first part of the twentieth century, the American yard (and hence other length measures) were different from the British measures. The British based their units on a standard length of metal. The Americans used to use the same standard, but in 1893 changed their standard to a fraction of the French standard metre (or meter, since we are talking about Americans!) The British seem to have done the same thing in 1878, but chose a very slightly different fraction of the metre. The units from the two countries were extremely close together, but not identical. This mattered for fine machining, especially in WWII, when machine parts made in the different countries were found to be of subtly different sizes and therefore not interchangable. In 1959, an international yard, based on the metre (or meter!) was agreed by Australia, Canada, New Zealand, South Africa, the United Kingdom, and the United States. The US started using this immediately. The British put this new standard into law through the Weights and Measures Act of 1963. The change increased the length of the yard in Britain by about one ten-thousandth of an inch. See history of the yard in Britain and United States, and the international yard. See below for US Survey Foot.

Military Pace and Tierce

A correspondent tells me that according to "The Great Volume" published in 1930 (which describes units) a Military Pace is two and a half miles. She was also puzzled by this quote from a Southern general in the American Civil War: "In the existing state of affairs every hour that elapses fortified the strength of the North while it correspondingly diminishes that of the South. Not an additional bale of cotton, or hogshead of tobacco, or barrel of flour, or fierce of rice is produced in the slave-holding States that does not contribute directly or remotely to such a result." Bale, hogshead and barrel are conventional units, but what was 'fierce'? Some research suggests that it is a misprint for 'tierce'. A tierce is a cask larger than a barrel, and smaller than a hogshead or a puncheon, in which salt provisions, rice, etc, are packed for shipment.

Board foot

There is a volume of measure for lumber in the US called the board-foot. A board foot is 144 cubic inches (or 1 foot x 1 foot x 1 inch). Rough lumber is sold in it.


A correspondent says:
"You may be interested in knowing about the 'acre-foot'. Here in the USA it is used in reference to reservoir size and is the amount of water needed to cover an acre to the depth of one foot."

Another correspondent gives from his FUI (Fund of Useless Information):
"It needs 22,000 gallons of water to cover an acre of land with one inch of irrigation."

Penny nails

A correspondent says:
"Here in Canada, nails (devices used for fastening wood) are gauged and sold by their length. If we need a nail 2" long, we buy a bag or box marked '2 inch nails' (we haven't come to terms with 5cm nails yet). I was aware that Americans didn't buy nails this way: instructions may call for 'four-penny nails', but I've never known what size that was.
I recently discovered that a penny means half an inch, so that a two-inch nail (Canada) is a fourpenny nail (USA). (Note that a one-inch nail is a two-penny nail, not a tuppenny nail!) And then, even more recently, I found boxes of nails sold as '3d nails' and some '4d nails'."

I have a vague memory of x penny nails, but only to describe how many it cost to buy a hundred.

Another correspondent adds:
"...about your comments on pennies as sizes for nails in the US. You describe a penny as half an inch, but it's not really that simple. Originally, an n-penny nail was a nail for which 100 nails cost n pennies (I presume US cents). Since both the length and diameter of a nail are involved in determining how much steel is in one and how much they cost, a penny can't just be a unit of length. I never knew the details, but there's a Wikipedia page with a table. A 2d nail is 1 inch long. After that, each additional d adds 1/4 inch to the length of the nail until you reach a 10d nail at 3 inches. But then a 3 1/4 inch nail is a 12d one, a 3 1/2 inch nail is 16d, and then the number of pennies grows faster and faster. A 6 inch nail is 60d."

Strange measurements

In 1958, students in a fraternity at the Massachusetts Institute of Technology used Oliver Reed Smoot Jr. (a fellow student) to measure the length of Harvard Bridge (between Boston and Cambridge, Massachusetts). So a smoot is his height, 5 inches 7 inches. The bridge's length was measured to be 364.4 smoots plus or minus one ear, with the "plus or minus" intended to express uncertainty of measurement. The markings on the bridge are repainted each year by students. They have become so well-accepted by the public, that during the bridge renovations that occurred in the 1980s, the Cambridge Police department requested that the markings be maintained, since they had become useful for identifying the location of accidents on the bridge. The renovators went one better, by scoring the concrete surface of the sidewalk on the bridge at 5 feet and 7 inch intervals, instead of the conventional six feet.

The barn-megaparsec combines very large and small scales. A barn is a very small unit of area used in nuclear physics, equal to 10-28 m². The effective area for interaction of the nucleus of an atom is on the order of magnitude of the barn (itself humorously named after the proverbial "broad side of a barn"). When this is multiplied by the megaparsec - a very large unit of length used for measuring the distances between galaxies - the result is a human-scaled unit of volume approximately equal to 2/3 of a teaspoon (about 3.0857 ml).

The beard-second is a unit of length inspired by the light year, but used for extremely short distances such as those in nuclear physics. The beard-second is defined as the length an average physicist's beard grows in a second. Kemp Bennet Kolb defines the distance as exactly 100 Angstroms while the Physics Handbook has it half the size at 5 nanometers.

Helen of Troy (from the Iliad) is widely known as "the face that launched a thousand ships." Thus, 1 millihelen is the amount of beauty needed to launch a single ship. Since the original quotation was "Was this the face that launch'd a thousand ships and burnt the topless towers of Ilium", a more accurate definition of the millihelen might be the amount of beauty required to launch a single ship and ignite a wastebasket.

Gun gauges

A correspondent writes:
"...gauge as a measure of the size of a gun (normally a shotgun). On our side of the pond, anyway, common sizes for shotguns are 20 ga. (which is smaller) and 12 ga. (which is larger), but in the past there were 10 ga. guns, and as a kid I had a 28 ga. Gauge measures the bore of a gun (the diameter of the barrel). It takes 12 balls of lead the diameter of the barrel of a 12 gauge gun to weigh a pound, and 20 balls of lead the diameter of the barrel of a 20 gauge gun to weigh a pound. Thus, it's a reciprocal measure, larger gauges meaning smaller barrels. Oddly, the smallest shotguns (my grandmother had one of these) are .410 bores. This not related to gauge; instead, a .401 has a barrel with a diameter of 0.410 inches. It's therefore measured just like the caliber/calibre of rifles or handguns. As usual, there's a Wikipedia article."

Old cake recipe

Apparently, America used to have Election Cakes, (see BBC article. These were "enormous and filled with alcohol and fruit with the intention of getting men to vote." The artice has a photo of an old recipe - unfortunately only the start! But it included the ingredients and amounts. I was interested to see that these were all weights, not cups:

5 lb flour
1 3/4 lbs butter
2 lbs sugar
2 lbs raisins
one nutmeg
half pint brandy
one gill sherry or Maidera wine
one pint yeast
one quart new milk

I don't know what this would be like as a cake! For a comparison, the standard Victorian sponge mix is equal weights of SR flour, butter, sugar and eggs, and a fruit cake recipe of mine includes 3 oz butter, 3 oz sugar, 2 eggs (about 4 oz weight), 4 oz plain flour, 8 oz dried fruit. The election cake seems to have no eggs, and a lot more flour, and less dried fruit than a modern cake. It is a yeast cake, of course. But note - no cups! You would need scales, and the only volume measure is quart or pint.

US Survey Foot

The splendid xkcd describes the US Survey Foot. Apparently, the British foot and the US foot used to be slightly different (see above Difference between yards). Then they agred to use the Internal Foot, defined as one inch=2.54cms (and 12 inches = a foot), which fell between the two values. This US Survey Foot seems to have hung in there...

xkcd US Survey Foot cartoon

Other units

The equally splendid SMBC meantions some other units.

smbc US units cartoon

How you order beer in Australia

A correspondent pointed out that Australia has fun names for different measures of beer. I investigated, and I agree with him! The following table uses data from a website on Ordering Beer in Australia. The Australian fluid ounce is the Imperial fluid ounce, so their pint (where used) is the same (except in South Australia). Some of the measures apparently only apply to some pubs within the given region, and if you buy a foreign beer such as Guinness, you may buy it in pints, even in state which doesn't usually use the word. I am distinctly worried that the same name buys you different amounts of beer in different parts of Australia. South Australia seems distinctly mean, and Western Australia has a very generous Pot. I do like the Pony and the Shetland, but I'm afraid that it has completely ruined my idea of Australia as a serious beer swilling nation! Drinking beer in units of a fifth of a pint?
I have been quite rightly taken to account for this gross libel on Australian drinking capacity, by this correspondent: "In hotter climates, well-chilled lager rapidly heats up to be too warm to drink if served in larger measures. Hope this sheds some light on this practice."
I have also been repremanded for saying that Australia has fluid ounces. "Imperial fluid ounces (abbreviated Imp. fl. oz) have not been used to measure the volume of beer in beer glasses used in Australian pubs for nigh on 30 years. The beer glasses used in most Australian hotels are those beer glasses usually authorised by each state's branch of the Australian Hotels Association (AHA) or, occasionally, some other industry organisation licensed in that state or territory under regulations pertinent to that state's statutory licensing law. These glasses are usually stencilled with the AHA logo (or other official body's logo or initials) with the interior volume of the glass shown stencilled in *millilitres* (ml). " This may be legally true. But if the standard glasses are a whole number of fluid ounces, and the equivalent metric measurements are weird numbers like 568ml, then the glass sizes are based on fluid ounces, even if they are stamped with metric measurements. No-one EVER said "Give me 568ml of beer"! If you really want the metric amounts, see the bottom of this webpage.

The first table lists the glasses by name and state:

New South WalesNorthern TerritoryQueenslandSouth AustraliaTasmaniaVictoriaWestern Australia
Jug  40 fl oz    
Pint20 fl oz  15 fl oz 20 fl oz 
Schooner15 fl oz15 fl oz15 fl oz10 fl oz 15 fl oz 
Middy10 fl oz 10 fl oz   10 fl oz
Handle 10 fl oz  10 fl oz  
Pot  10 fl oz 10 fl oz10 fl oz20 fl oz
Ten  10 fl oz 10 fl oz  
Eight    8 fl oz  
Seven7 fl oz7 fl oz7 fl oz    
Beer  7 fl oz    
Butcher   7 fl oz   
Glass     7 fl oz7 fl oz
Six    6 fl oz  
Small Glass     6 fl oz 
Bobbie      6 fl oz
Pony5 fl oz  5 fl oz 5 fl oz5 fl oz
Five  5 fl oz    
Small beer    4 fl oz  
Shetland      4 fl oz

If you are a little confused by this, here is the data rearranged by volume:

New South WalesNorthern TerritoryQueenslandSouth AustraliaTasmaniaVictoriaWestern Australia
40 fl oz  Jug    
20 fl ozPint    PintPot
15 fl ozSchoonerSchoonerSchoonerPint Schooner 
10 fl ozMiddyHandleMiddy, Pot, TenSchoonerHandle, Pot, TenPotMiddy
8 fl oz    Eight  
7 fl ozSevenSevenSeven, BeerButcher GlassGlass
6 fl oz    SixSmall GlassBobbie
5 fl ozPony FivePony PonyPony
4 fl oz    Small beer Shetland

In my 'local' (pub) in England, a jug is 4 pints, or 80 fl oz. So there! (But you're not supposed to drink it all yourself).

Super foot

Another correspondent:
"My father was a carpenter as was father and grandfather, and in my youth I regularly overheard them using the term 'super foot', which in short was 1 foot x 1 foot x 1 inch. Prior to changing to metric measures, I found the term commonly used throughout Australia; I am led to believe that it came from the UK."

A correspondent answers this:
"The use of super in conjunction with area measurement is short for superficial. All materials ordered from quarries whether hoggin, graded chippings or tarmac, are ordered by the yard or metre. These are cubic yards or cubic metres. Therefore a '10 yard load of tarmac' is actually 10 cubic yards. When the tarmac is spread 3" thick, the area covered is 120 super, or 120 square yards. In each case the word 'cubic' or 'square' is omitted but the words 'yard' or 'super' make the meaning absolutely clear. The Shorter Oxford English Dictionary gives one of the meanings of 'superficial' as meaning 'relating to or involving two dimensions; esp. relating to extent of surface'".

However, the 'super foot' seems to be a cubic measure rather than an area or square measure.

Another correspondent:
"In New Zealand the super foot was the standard measure for milled timer being 144 cubic inches. I spend many years in timber as did my father and great grand fathers. All large quantities of timber were described in super feet which was very handy for recutting.  Stocktaking in the timber yards, sales analysis and buying was similarly calculate in super feet. it was easy to estimate the timber in a bundle or packet by eye. Super feet slowly died out when we officially went metric in about 1975 but as you can imagine many of the old hands still used super feet to communicate with others skilled in the measure.  The conversion from super feet to lineal feet of a board was easy. Conversion of a metric cube to lineal feet is much slower if done on the spot mentally."

The 'super foot' seems to be the same size as the American board foot.


Australia has metricated far more efficiently than the UK, but a correspondent notices one area less metric:
"It occurred to me as I was complaining to friends about the lack of surf (none for a week) that down at the beach things are for some reason a bit Imperial. My boogie boards are described as "41","41 and a half" and "44" (inches without statement) and my boards are "seven six", "seven four" and "nine six" (feet and inches). Widths and thicknesses are always in inches so the "nine six" is sometimes "nine six, twenty-two, two and seven eighths" . Never heard any board described metrically.
The most unmeasurable thing of all (in as much as no two people ever seem to agree on a figure), wave height, is in metres on the BOM buoys sites, but always talked of in feet at the beach, (although there seems to be a recent trend to a reversion the non-standard knee- hip- chest- head-high which at least is understandable apart from the mystical "double overhead" which is puzzling)."

Mallorca boatbuilding

A correspondent wrote:
"As a naval architect, I was interested by an oddity of measurement I encountered in a shipyard in Palma, Mallorca. This was in 1991, and an old shipwright who specialised in woodwork in the yard explained to me that the smallest measurement that they bothered with (traditionally) was an eighth of an inch. As my Mallorquian was (and is) pretty poor (i.e. non-existent) and his English only marginally better, I assumed he meant 3mm, but on further discussion he insisted it was 1/8th of an inch, and demonstrated this on an Imperial rule we had on board (it was a British boat we were working on). He did tell me the Mallorquian word for this, but I couldn't begin to pronounce it even then, let alone recall it now. There is a very old tradition of wooden boatbuilding in Mallorca, and the Balearics have had many rulers and international influences over the centuries, but quite how they ended up with this anomaly I don't know."

Chilean and Argentinean artisans

A correspondent wrote:
"I was in Patagonia, Southern Argentina in 1962/3, and the Chilean and Argentinian artisans there used a pulgather as a unit of measurement, and they used Imperial rulers graded in inches to measure them. The translation from the local Spanish dialect is 'thumb'. The width of a thumb is about an inch. I believe this unit may also be used in Spain and other former colonies of that country."

See here and here for more 'thumbs'.

Non-metric units in France and elsewhere

A correspondent wrote:
"Imperial measurement is still used in France, of all places, for the measurement of ploughing. Primarily the depth of ploughing is measured in pouces or inches, and occasionally the width of the furrow is also in pouces although there is a trend nowadays to use a metric width with an imperial depth, due I believe to the manufacturers being forced to sell their ploughs in metric dimensions. The farmer decides the depth he will plough and as this dimension is not controlled by Brussels he still uses pouces for the depth. I conduct business with farmers in France and although they all talk of pouces I have never found any French farmer who uses an imperial ruler and consequently I carry some dual imperial/metric tape measures to give away as 'freebies' whenever my contact mentions pouces. In French pouce means thumb as well as inch and in the respect of measurement the use of one word for both definitions is perhaps sounder than the English use of different words. Since the replacement of the franc by the euro with its associated inflation, rural France has been very much against the EU, particularly in the south (although they welcome the largesse with grasping hands), and the farmers enjoy cocking a snook at Brussels at every available opportunity. Hopefully pouces will remain the ploughing depth measurement for a while longer. Even after 200 years Napoleonic law has not suppressed all the old ideas."

See here and here for more 'thumbs'. Click here for the origin of the word 'inch'.

Words meaning 'pound' are still used in France (livre) and Germany (Pfund), but now they mean half a kilogram (which is fairly close). Apparently before French metrification, France had a unit of length called pied du roi, or 'foot of the king', which was 1.066 English feet.

This article about Imperial measures in the BBC Magazine website says that "The English foot, for example, is almost identical to the Japanese Kanejaku, and both are as long as the sole of an average man's shoe. The Kanejaku is 11.83 inches." This is not because they are connected, but because they are both based on the same thing, a man's foot.

From a friend, living in Spain. "Computer, TV and phone screens are measured in inches. I have recently bought a Chinese phone from amazon.es and the screen is in pulgadas. That is inches, based on pulga, which is a thumb."

From QI (Twitter): "Napoleon was slightly taller than the average Frenchman of his time. After his death his height was recorded as 5 foot 2, but that was in French inches. In English measurements he was 5 foot 7 (1.69m)." So at that time, French inches were slightly bigger than English inches. I wondered why Napoleon, who died on Saint Helena under custody of the British, was measured in French inches. He was buried in Saint Helena, in 1821, but the body was returned to France in 1840, where he had a state funeral. I don't know when he was measured, but apparently the body was in a good state of preservation, so perhaps it was then. Or perhaps the British deliberately measured him in French inches to make him seem smaller!

Agricultural unit of volume in France and Ireland

A correspondent wrote:
"The jointee is an obsolete term in French agriculture. This term means the amount of grain you can scoop up with joined hands (not a handful, a cupped hands-full) and was once an official term that is still in older dictionaries. There seems to be a similar unit in Early Irish Farming, a mam, defined further as holding 1,000 grains."
However, in British weights, an ounce avoirdupois was 437.5 grains, which were originally grains of wheat. Now, I would have thought that someone could hold a lot more than two ounces of wheat in both hands, cupped. So I suspect that a mam was a single handful. If anyone knows anything about this, please let me know.

German weights

I have already mentioned that the modern German word Pfund (or pound) now means half a kilgram. Germany is, of course, now metric. I investigated the pre-metric weights of Germany following a request from a correspondent.

The webpage Metrische Eisengewichte vor 1868 shows various labelled weights.

One has 1/2C on one side and 50 Pf on the other, and is described as 1/2 Centner. The German for hundredweight is Zenter, but here it seems to be called Centner and is abbreviated to "C". We can tell that it is a hundredweight, because it is 50Pf or 50 Pfunds (pounds). A hundredweight is so-called, because it is (roughly) 100 pounds. The English hundredweight (cwt) is actually 112 pounds (lb) but these things happen... I thought that German doesn't use the letter C, but I've been told that German nationalism around this time started to remove foreign influences from the language, such as the letter C. So perhaps this dates to before that change. Germany didn't became a nation state until 1871.

Another weight is labelled 25P (25 Pfund).

A third has 1/2 ZP (1/2 Zollpfund). "Zoll" means "tax". This suggests that either there were different versions of the Pfund (pound) or perhaps different names in different places.

Then there are various multiples of Metrische Pfund (metric pound) - another varient of Pfund. This is abbreviated as M and a glyph for Pf - see right).

There are some Zoll-Zentner weights, abbreviated as ZC. The webpage is using Zentner to mean hundredweight (rather than Centner) but the abbreviation uses C for Zenter, see above. This shows also that there is Zoll-Zentner as well as Zollpfund.

German weight

Weight used in Spain and Portugal

Arroba was a Portuguese and Spanish unit of weight. It derived from Arabic ar-rub or "quarter," specifically the fourth part (of a quintal), which defined the load that a donkey or mule could carry. The arroba was equal to 32 pounds (14.7 kg) in Portugal and 25 pounds (11.5 kg) in Spain. Arroba and bushel as weight units are similar (15 kg). (This is from Wikipedia - I've never heard of bushel as being anything but a meaure of volume.)

The arroba is still used in Portugal by cork merchants, and in Brazil by the agricultural sector. The modern metric arroba used in these country life activities is defined as 15 kilograms (33 lb). In Peru the arroba is equivalent to 11.5 kilograms (25 lb). In Bolivia nationally it is equivalent to 30.46 litres (6.70 imp gal; 8.05 US gal). However locally there are many different values, ranging from 11.5 litres (2.5 imp gal; 3.0 US gal) in Inquisivi to 16 litres (3.5 imp gal; 4.2 US gal) in Baures. These are, of course, volume measures rather than measures of weight.

The symbol for arroba is @. In Spanish-speaking and Portuguese-speaking countries, "arroba" has continued as the word for the "@" symbol used in Internet email addresses. In Britain "@" originally meant "at". I remember seeing something like "5 apples @ 6 pence each = 30 pence". You could say "Someone lives at this address" but I never saw the @ symbol being used in this way. But now we use @ in email addresses all the time.

This description mentions "quintal" - a donkey load. Kipling mentions quintal in Captains Courageous as a measure of fish, used by the American fishermen on the Grand Banks, off Newfoundland. A full ship's hold was "fifteen hunder quintal". The quintal or centner is a historical unit of mass in many countries which is usually defined as 100 base units of either pounds or kilograms. It is commonly used for grain prices in wholesale markets in India, where 1 quintal = 100 kg. In British English, it referred to the hundredweight; in American English, it formerly referred to an uncommon measure of 100 kilograms. But the Spanish and Portugese quintal seems to have been closer to 100 pounds.

Mexican small volume measure

A correspondent wrote:
"I have lived in Mexico for many years, it being of course a metric country; however in many country markets away from the towns there is a common volume measure for dry goods, which is called a 'sardine' (sardina in Spanish) used by simple country folk to measure out small items such as nuts, cherries or beans. They use a used flat oval sardine tin (without its top) to scoop out the berries from the pile then using a piece of wood they skim off the excess level with the edges of the tin. There you have it. A sardine!

Scandinavian and German fathoms

A correspondent wrote:
"The English word fathom is related to the German word Faden, which is also the general term for 'thread'. A Faden would thus originally have been the length of rope or thread you could stretch between the hands with the arms outstretched."
It's been pointed out to me by another correspondent:
"This comes from the manner of using what was originally an unmarked line to find the depth. Stretch the line across the chest as the former is pulled in. For most men this distance is in the order of six feet. A useful tip when a properly marked lead line is not available."

Another correspondent wrote:
"I should tell you that the Scandinavian nations all have archaic units of essentially the same name: Swedish famn, Danish and Norse favn. The Scandinavian languages also have a suitably cognate "embrace" verb to match famn/favn - for example, my Norwegian dictionary gives me the verb omfavne and noun omfavnelse (om = about; -e to -else is a standard nouning of a verb) - which is what my Norse friends clearly believe favn to mean; so we can as readily credit the fathom's name to Vikings - who are known as having made a significant contribution to British maritime culture. The assorted fathoms are all 3 ells (Swedish aln, Danish and Norse alen), an ell is two feet (Swedish and Norse fot, Danish fod) and a foot is twelve inches (Swedish tum, Danish tomme, Norse tom - these words all mean thumb). We thus have a whole family. Each family has the same ratios, but there are minor divergences as to the exact value of the units: relative to the English unit, Danish and Norse are about 3% higher, Swedish is about 3% lower. (The Swedish foot thus works out at a quite close approximation to the "light nano-second".) So I believe it's fair to say that all of these units are ancient; it's possible they date from, say, the Hanseatic league propagating a standard set of units, but they may equally date back to the point of linguistic divergence of the Germanic and Scandic tribes - most of two millennia, I think.

See here and here for more 'thumbs'.

Channel Islands measure of land

In the Channel Islands, a vergee is a standard measure of land, but the statutory definition differs between the bailiwicks.
In Guernsey, a vergee (Dgernesiais: vergie) is 17,640 square feet. It is 40 (square) Guernsey perches. A Guernsey perch (also spelt perque) is 21 feet by 21 feet.
In Jersey, a vergee (Jerriais: vregie) is 19,360 square feet. It is 40 (square) Jersey perches. A Jersey perch (also spelt perque) is 22 feet by 22 feet.
For comparison, an Imperial perch (the area measurement) is 272.25 square feet, the Guernsey perch is 441 square feet and the Jersey perch is 484 sq feet - rather a difference!

Furlongs in India

A correspondent wrote:
"People over the age of about 65 years in India still use the term furlong in everyday speech. 'The tea shop is only two furlongs away', etc. I've heard all my dad, dad-in-law, and sundry uncles all use the term."

Money in South Africa

A correspondent wrote:
"In your money page you mention (and show) the old silver three-penny coins. South Africa decimalized before the UK - I believe it was around 1960. I visited Cape Town on the old Union Castle mail ships when I was 19 (I shall be 70 this year - 2010) and my cabin steward told me not to give the countless beggars one encountered on the days the ships docked anything more than a 'tickie'. A 'tickie' was still the silver 3d coin in those days. All currency in South Africa was still in £.s.d. and I believe minted and printed by the Royal Mint. "

Weight in South Africa

A correspondent wrote:
"I was an assizer (inspector of weights and measures) in South Africa for almost forty years. Young assizers were often sent to a senior official to fetch a long weight (wait). "


From a correspondent:

ChinesePaper sizes are on the trades page.


The units of length can be divided into two categories: Ordinary (decimal) and Surveying (non-decimal).
There are 3 base units in ordinary units: chi, the maximum length a man can make between the end of thumb and of middle finger; cun, somehow related to thumb but I don't know; fen, the lesser diameter of a millet grain. They are decimally defined as 100:10:1. The names for decimal multiples of chi are zhang for 10 chi and yin for 100. There are also names for decimal subdivisions for fen but they are of little use in real life.
The first unifying standard in 3rd century BCE converts to 23.1 cm per chi. It is recorded that a bronze standard was made at 10 chi (2.31 m) and a bamboo standard made at 100 chi. Probably the bamboo standard was intended for land survey, but it was so hard to carry that there is a separate set of units for survey.
The base for survey unit is bu (meaning "step"), equal to 6 chi (148.3 cm) and approximates two human steps. 300 bu makes a li, which was 3 continuous sections of agricultural field in ancient times. I don't know why it is not 10 sections (which would be 1483 m), while being so obsessed with decimal. For some time in history, bu was used for horizontal distance while zhang for vertical ones, but later zhang prevailed. Other units include zhi (8 cun) and xun (8 chi), intended as "woman's" chi and zhang because of smaller hands. Ren was also 8 chi, but came from the distance between ends of middle finger when arms are horizontally streched out, and was only used for height and depth.

Again, there are ordinary units (squared length) and survey units, but both are decimal. 100 square bu made a mu (a "section" mentioned above), which later changed to 240 for reasons I don't know. 100 mu makes a qing.

The base unit is sheng, equaled the volume occupied by 24 thousand grains of millet. The original record says "correced by well water", which probably means measured by displacing water. Ge was 1/10 sheng, and yue was half ge. The standard sheng of 3rd century BCE was about 200 ml, which works to about 8.3 mm³ for each millet grain, a pretty small amount.

Another field with extensive non-decimal units. The base unit is liang, first equaled to the weight of 2400 grains of millet. Liang was divided into 24 zhu (so one zhu equaled 100 grains of millet), while 16 liang made a jin, 30 jin made a jun and 120 jin made a dan (which literally means stone, a weird choice). The standard jin of 3rd century BCE was about 250 g, which made a grain of millet 6.5 mg and a dan 30 kg.

The civil system consists of equal and unequal units. In the day time people used equal periods, with one day equals 12 double-hours. At night, unequal watches were used, five from dusk to dawn, and were each divided into 5 parts. The astronomical system divides one day into 100 ticks, sometimes changes to 96, 108 or 120 to fit the 12 double-hours. The division of tick is different from time to time, and complete decimal division was used between 13th century and 17th century. Western timekeeping was introduced in 17th century, which changed a tick to 1/96 day and each containing 15 minutes.

The mystery of Chinese units is that they are not only fluctuating in time and place (which is common in all ancient units), but also constantly being rescaled. This is weird as there are no major incentives in rescaling them, and sometimes the change would be too large to be explained by "to collect more taxes". The first major rescaling occurred in 6th century, scaled the ordinary length units to 120% of the original, but survey units are largely unaffected. Li was either scaled (for being 180 zhang) or kept (for being 300 bu) in the subsequent dynasties. Meanwhile, the volume and weight units were rescaled to 3 times the original value. A 750-g jin became unpopular and that it fell back to around 600 g.
The second rescaling occurred in 13th century which made volume units to 140% of the original. As this is the time of Mongol invasion, it is probably done to align volume units with Mongolian ones. However, this rescale also makes sheng extremely close to one litre that sheng became the translation for "litre" when metric system was adopted. By 17th century, the definition of chi (being now 120 side-by-side millet grains) seemed inconsistent with the decimal nature, and it was restated as 100 end-to-end millet grains.

Later reform and spread to other countries:
After the first major rescaling, volume units and weight units were adapted largely to be decimal. 1/10 of ge became shao (means "spoon", about 6 ml at the time) and its 1/10 became zuo. 1/10 of liang became qian (means "coin", about 3.7 g). It was the weight of a smallest coin, and its 1/10 became fen, recycling the name for length. Also, hu went from 100 sheng to 50, and dan was used as 100 (thus the name can be both volume and weight). Jun became obsolete.
This version of Chinese units spread to Japan and became the original Japanese units with different names. For example, kanejaku or shaku is essentially chi with a Japanese name, being redefined in 19th century as 10/33 of a metre. Korea and Vietnam also have similar systems.
In 1929, chi became 1/3 m, li became 500 m, jin became 500 g and sheng became 1 L. Another reform in 1959 made 1 jin equals to 10 liang instead of 16, as a prelude of metrication. TCM medicine were excluded in the reform to prevent underdose or overdose, and they only got metricated in 1980s using the earlier conversions.