I have done a post on old money (pounds shillings and pence) and the Imperial units of measurement were even more complicated than the old monetary units; and whereas £sd has completely disappeared, some Imperial units remain in official use.
There were so many divisions to remember; in weight you went from ounces to pounds and thence to stones, hundredweights and tons. Sixteen ounces made a pound, and fourteen pounds made a stone. There was a long and a short hundredweight; the long hundredweight had become the norm by the time I was learning my measurements. There were 112 pounds to a long hundredweight and that equates to eight stones. A hundredweight had however got its name from the short hundredweight of 100 lbs. The hundredweight was abbreviated to cwt, which is itself a mixture of Latin and English (‘c’ for centum, a hundred, plus ‘wt’ for weight). Following on there were 20 cwt to the ton; long or short tons, depending on the number of pounds to the hundredweight.
Then there were the smaller units of weight, 16 drams to the ounce and almost (but not exactly) 44 grains to the ounce. A pound is represented by the abbreviation lb which stands for the Latin word libra or librum in the singular. An ounce is abbreviated to oz, but how did the zed get there? Feet were abbreviated to ‘, and inches to “. A bushel was normally a measure of dry volume, but it equated to the liquid measure of 8 gallons.
It was a complicated system, but things are now even more complicated; we are officially on the metric system, but stones are still commonly used for body weights (particularly among the older generation who ‘put on a stone or two’) and babies are normally announced to the world as weighing so may pound, rather than kilos. When I go to hospital my height and weight are given in metric measurements, but otherwise I stick to the old terminology. I can understand what it is to be six feet tall, but I am still rather puzzled by a height of 182.88 cms. A one foot ruler is no longer used in school, but a 30 cm one has taken its place, which it the same length to all intents and purposes.
The widths of domestic water pipes are still measured in inches, and the threads are still the old tpi (threads per inch); if we went over to metric we would have to replace the entire country’s water supply. We still measure speeds in miles per hour, not in kilometres. Even road signs still announce the miles from London to Cambridge. In measuring length kilometres now ought to follow on from centimetres and metres, but for some reason they don’t. In Great Britain MPG (miles per gallon) is still a commonly used term, although it ought to be KPL (kilometres per litre) exclusively. When I go into a pub I still buy a pint of beer, although I may well get a half litre of lager at the supermarket; a 440 ml can is a common size, and that equates nearly exactly to a pint. Milk is sold in pints or litres without any apparent rhyme or reason. On the other hand it is illegal to sell a pound of apples, and at one time shopkeepers were actually prosecuted for doing so. I feel sorry for the youth of today who are only taught the metric system at school. When they enter the real world the must attempt to learn elements of the old Imperial system too.
The metric system was invented by the French at the time of the Revolution. Out went all the old measurements in favour of the new, based on the number ten. There was an attempt to unify all measurements, so that (for example) a litre of water weighed a kilogramme, only they didn’t get their calculations quite right. They even tried to introduce the metric system to the measurement of time; however the ten day week proved to be an innovation a step too far and the Revolutionary calendar lasted under twenty years. I do not remember what was proposed for minutes and seconds, but the metric system did not stick and the sixty minute hour and the 24 hour day remain universal.
Acres have been replaced by hectares as a system of area measurement, but the basic unit of an ‘are’ is completely unknown, although it exists in theory. There are 10,000 square metres to a hectare; square metres are the normal measure of area for smaller units.
The Americans still use the old units in most circumstances, but in many cases this differs from the Imperial system. Feet and inches are the same, but the US gallon is significantly smaller than the Imperial gallon, and the pint (which is 1/8th of a gallon in both systems) is also smaller in America. This retention of the old system by America (arguably the most important nation on earth) has its odd moments. There was that occasion when a space programme went wrong because the Americans were using feet and inches while their European comrades were using millimetres and metres. That most modern piece of equipment, the computer, will have its screen size stated in old-fashioned inches. Although the metric system is not widely used in the US, the American spelling of meter rather than metre is becoming increasingly common in this country.
Is considering all these measurements making your head spin yet? Mine is, so I will stop.