Saturday, March 22, 2014

Imperial measures

click photo to enlarge
When I was in primary school (age 5 to 11 years old) every exercise book we used had useful information on the back. This included a list of most of the common Imperial units of measurement. Talking to people I've discovered that this was common to most areas of the country and accounts for the fact that 1,760 and 5,280 are significant numbers for people "of a certain age" (they are the number of yards and feet in a mile). Ask anyone of this era the name for a distance of 22 yards (the length of a cricket pitch) and they will immediately rattle back, "a chain". If you are fortunate they will go on to bore you with the fact that a chain is one tenth of a furlong (itself 220 yards), the latter is one eighth of a mile, and furthermore its name derives from the distance a team of oxen would plough (a furrow long) before resting, then turning and ploughing back again. However, if you press them, most will confess scant knowledge of the rod, pole and perch, measures that were archaic or specialised by the time of the mid-twentieth century but, nonetheless appeared on the backs of those exercise books.

A unit that will most definitely be recalled is the hundredweight (112 pounds, with 20 to the ton). It was an important measure at the time, continued after the metric system was introduced in the 1970s, and is still sometimes used today. The abbreviation is easy to decipher with the "c" standing for the Roman 100. What was never made clear to me is why the extra 12 pounds is involved. In fact, it's only in recent years that I realised it is 8 stones (a stone being 14 pounds). The Oxford English Dictionary (OED) notes that over the years the hundredweight has varied between 100 and 112 pounds. The former is sometimes called the "short hundredweight" and is favoured in the United States whilst the higher figure reflects British Imperial measure and has been called the "long hundredweight".

I came across the hundredweight (cwt) when I photographed an old brass warning sign (above) that was for sale on a stall selling railway memorabilia. Fifty cwt is two and a half tons so perhaps the electric safety lift in question was designed to carry more than people - or maybe a lot of very big people! Old signs are full of character, often much less clear than modern signs, but so much more durable.

photograph and text © Tony Boughen

Camera: Sony RX100
Mode: Aperture Priority
Focal Length: 23mm (62mm - 35mm equiv.)
F No: f3.5
Shutter Speed: 1/80 sec
Exposure Compensation: 0 EV
Image Stabilisation: On