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Of the earliest standards of length the principal were the palm or handbreadth, the foot, and the cubit
(from elbow to tip of mid-finger). There were two leading cubits : the natural cubit in Egypt, Chaldea,
Phœnicia, and Greece = 6 palm., = 2 spans = 1.5 foot = 18.24 inches; and the royal cubit of Memphis,
found also in Babylonia and Chaldea = 20.67 inches. The Greek foot (= 12.16 inches) passed into Italy and
was there divided into 12 unciæ., (inches); it was afterwards shortened, becoming as small as 11.65 inches.
The Romans used a 3-foot ulna. The Saxons used an ell or yard of 36 inches, based on the Roman foot. This
was continued by the Normans in England, various modifications occurring in the ell. Henry VII. and Elizabeth
made standard yards of 36 inches. Henry's was 35.963 inches of the present standard Elizabeth's was about
1/100 inch short of the present yard. In 1742 the Royal Society of London made a standard 42-inch scale; in
1760 Mr Bird made for a Weights and Measures Committee of the House of Common. a copy of an old yard-measure
found in the Tower. In 1824 this copy was legalised as the standard yard, with the direction that in the
event of its being lost, the standard was to be recovered by making the length of a meantime seconds pendulum
in the latitude of London, in a vacuum at sea-level equal to 39.1393 inches. In 1834 the standard was destroyed
in the fire at the Houses of Parliament. In 1838 a committee was appointed under Mr Airy, astronomer-royal;
in 1841 they reported against the accuracy of the pendulum-method; in 1843 they were appointed as a commission
to restore the lost standards; this they did between 1843 and 1854 by taking the best secondary evidence and
they produced a standard bar of gun-metal, the distance between two lines on which, crossing two gold studs,
is one yard at 62°F. and 30 inch bar. pressure. This was legalised as the standard. Parliamentary copies are
lodged at the Mint, the Royal Observatory, Greenwich, with the Royal Society of London, and immured in the
parliament buildings, Westminster; while copies have been supplied to many towns. The Weights and Measures
Act of 1878 regulates the law, renders all old local or customary weights and measures, other than imperial
ones, illegal, and enacts penalties on false and unverified weights and measures varying from £5 to £50.
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Two-thirds of a cubit, we have seen, made a 'foot;' a cubic 'foot' of water weighed a talent. When the 'foot' was
2/3 the royal cubit, the talent was 655,566 grains; this was the Egyptian, Hebrew, and Olympic monetary talent,
later known as the great Alexandrian talent of brass and the Egypto-Roman talent. A talent half this weight was
known as the Alexandrian talent of silver, or 327,783 grains ; this was divided into 60 minas of 5463 grains
each; these are the origin of the Saxon moneyer's lb. of 5400 grains = Mint lb. or Tower lb. = old apothecaries
lb. of Germany; one such lb. , in silver coins, was the original form of 'one £ sterling,' and was divided into
20 'shillings' or 240 'pence' or pennyweight ; each dwt. was divided into 32 monetary grains (wheat-grains),
each equal to 0.703125 modern grain. The Tower weight was abolished in 1527. The Saxon ounce contained 416.5
grains = nearly, Roman uncia = 1/12 libra ; the libra ( = 5015 grains) was the Greek-Asiatic and Persian mina
of 5015 grains. The Troy lb. is 5760 grains = 12 oz. of 20 dwt. each. Troy weight is now restricted to gold,
silver, and jewels except diamond and pearls; the latter are weighed in carats (= 3.1683 grains), which were
originally 1/144 the Alexandrian ounce (the twelth part of the mina of silver). Various larger Ibs were early
used for merchandise; in 1303 the avoirdupois' lb. (=7000 grains) was in use. The Troy lb. standard made by
Mr Bird in 1758 for the Weights and Measures Committee was legalised in 1824; in 1834 the standard was
destroyed; the Standards Commission replaced troy weight by avoirdupois, and the standard lb. is a mass
of platinum weighing 7000 grains in vacuo, copies of which are distributed as in the case of standards
of length. The standard of capacity is the gallon, which was in 1824 adjusted so as to contain 70,000
grains, or 10 lb. avoirdupois of water at 62°F. and 30 inches bar. pressure; this gallon occupying
277.274 cubic inches, instead of the old Winchester gallon of 274¼ cubic inches. The French or Metric
System of weights and measures is based on the Decimal System (q.v.); and See METRE, ARE, GRAMME,
LITRE.
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See Chisholm's Weighing and Measuring. Kelly's
Universal Cambist, Tate's Modern Cambist, Whiteley's Law
of Weights and Measures, Ridgeway's 0rigin of Metallic
Currency and Weight Standards (1892); the articles on the
various measures; also AVOIRDUPOIS, DEGREE, GRADUATION,
GRAVITY, Troy WEIGHT, UNITS, &0.
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