But in the British empire, it took 20 (fluid) ounces to make an imperial pint, making the Imperial gallon 25% bigger than the American gallon.
Thus, we have the common American claim that "a pint is a pound the world around" pitted against the English statement that "a pint of water weighs a pound and a quarter".
But in England, it got a lot worse, because there were two different ounces! Precious metals and apothecary goods were sold in troy (or apothecary) ounces of 480 grains each, while everything else was traded in avoirdupois ounces of 437.5 grains each. Thus, the comforting fact that an ounce of gold (31.1 grams) weighs more than an ounce of feathers (28.35 grams). On the other hand, the troy pound has only 12 ounces, while the avoirdupois pound has 16 ounces, so a pound of gold (373 grams) weighs LESS than a pound of feathers (454 grams).
Larger measures: A hogshead (238 liters) is 7 firkins (US) or just under 6 firkins (British) and I have heard it said that this is also half a pipe, but I have not found a written reference to the measure of a pipe.
A barrel (British) appears to be anywhere from 31 gallons to 42 gallons, although the most common definition seems to be 36 gallons (164 liters).
An American barrel of dry measure is 105 dry quarts (116 liters), but a liquid barrel is 31.5 gallons (liquid) or 119 liters, unless the barrel contains petroleum, in which case it contains 42 (US) gallons or 159 liters.
The three different ounces:
A rod/pole is 5.5 yards (16.5 feet):
The size of a big stick carried around by builders (hence the name).
Four rods make a chain (22 yards) - the distance between two (cricket) wickets. Ten chains make a furlong. A furlong square is ten acres. Eight furlongs make a mile.
A perch was originaly a big stick, but later became a volume. A perch was a pile of stone one rod long by one foot wide by one cubit high).
Fahrenheit's claim to fame was that he had a (proprietary) technique for making glass tubes with a constant inner bore. Thermometers that he made with that technique were exceptionally accurate. They still had to be calibrated, of course (it's deucedly hard to get exactly the right amount of liquid in the bulb), but once two marks were placed on the completed thermometer it was straightforward to interpolate other marks linearly in between, confident that because of the constant bore such marks would match the corresponding linearly interpolated temperatures.
Notice that both the position and spacing of the marks would vary from one thermometer to the next. It was tricky enough making each tube have a constant bore along its length. Making all the tubes coming out of the same factory have the same constant bore was too much to hope for. In any event the distance between marks still depends on the ratio of the volume of the bulb to the area of the bore, and he wasn't able to make that ratio so uniform.
It helps if the two reference temperatures differ by a power of two, because then interpolating the other marks is as simple as repeatedly halving the interval. He chose as his reference temperatures the temperature of melting ice and the temperature of his dog's rectum. (Poor mutt.) He assigned those temperatures the numbers 32 and 96, which differ by 64 degrees.
He started at 32 rather than 0 to better handle subfreezing temperatures. 32, also a power of two, simplified the task of adding the subfreezing temperature marks, and was enough to shift the range so that, as a fortuitous consequence, 0 would be "about as cold as it gets" and 100 would be "about as hot as it gets". "About", in both cases. 0 and 100 were not the reference temperatures; 32 and 96 were. He was thinking binary, not decimal.
-Ron Hunsinger - firstname.lastname@example.org
The pound was abbreviated "L" for "Libra" (latin for a pound of silver). The shilling was abbreviated "s" for "solidus", and the penny was abbreviated "d" for "denarius".
After the reform, there were 100 (new) pence to a pound, but visitors were quite confused, because the old coins remained legal tender. For example, the old sixpence coin was now 2 1/2 (new) pence; to avoid confusion, the new pence were abbreviated "p" (for "pence"). As old coins wore out, new coins were minted in the same shape but imprinted with the decimal value.
How could a system as complicated as the 1/20/12 ratios have developed ? One source claims that the three units originally were unrelated.
There was a unit of currency called the shilling. It was used by big business and worth quite a bit (about a month's wages). Its value went up and down as the medium of exchage -- a month's work -- became rare or plentiful -- high employment or low employment.
There was another unit of currency called the penny. It was the general medium of exchange for a bulk item (baker's dozen of loaves, a month's rent, travel from Oxford to London). It was divided into quarters so you could buy a single loaf or a jug of milk.
Another unit was used by huge business: the banks, shipbuilders, those who dealt in metals or in entire shiploads of goods. It was equivalent to the cost of a pound of silver.
There were also groats and sovereigns. I'm not sure about them.
These all existed independently. If you were the kind of person who dealt in pounds, there was never any need for you to encounter a penny. If you paid rent of a shilling a month for your house, you could never thing of seeing a whole pound. The different units of currency had constantly-shifting exchange rates depending on demand-and-suppply. If three trading ships came in at the same month all laden with goods, the value of the pound would go up with respect to the shilling and penny.
Eventually there was so much interplay between the different currencies that it became necessary to fix the exchange rates to stop a rich man keeping all his wealth in pennies because he thought that the pound was going to go down. At about that time, a pound was worth about twenty shillings and a shilling was worth about twelve pennies, so that's how they fixed it.
The disparate systems did not bother ordinary people. No need to know what a shilling was until you were old enough to pay rent. No need to know what a pound was unless you were a clerk, in which case you were trained. More recently (i.e. when I went to school) it was a standard part of early schooling.
I really don't believe any of this, but it is an interesting theory.
Back to the facts. Certain items were traditionally billed in Guineas. A guinea is one pound and a shilling. I have heard it claimed that this originated in real estate transactions, where the pound went to the seller, while the shilling was the lawyer's commission for doing the paperwork.
$Log: measure.htm,v $ Revision 1.4 2001/01/27 23:28:18 lars Added summary of english money. Revision 1.3 2000/06/15 01:40:40 lars Added link to sciencemadesimple.com Revision 1.2 1999/12/13 19:56:18 lars Corrected error in definition of the acre. Revision 1.1 1999/12/10 08:11:18 lars Adding new category for humor.