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IMPERIAL UNITS
MASS (WEIGHT)
GRAINA grain was said equal to the mass of an average grain of
wheat taken from the middle of an ear.
There 7,000 grains in the the avoirdupois pound and 5,760 grains
in the troy the pound.
SCRUPLEFrom the atin word s!rupus, a small rough pe""le or a
!hip of stone # "asi!ally, somethingsmall. A s!ruple is $0
grains.
PENNYWEIGHTAt one time %nglish pennies weighed $&
grains.
DRAMA fra!tion of an oun!e 'an eigth or a si(teenth depending on
the system). The word is derived fromthe an!ient *reek !oin the
dra!hma '+-/). 1ne dra!hma weighed a"out one dram. 2ram also
refers informally to a serving of whiskey, espe!ially 3!ot!h. 4n
this !onte(t, one might translatedram as a wee "it. 'An a!tual dram
of whiskey would not "e !onsidered an adequate serving,however. hen
someone says this, they are "eing witty.)
OUNCEThe word oun!e has the same origin as the word in!h # the
1ld %nglish word for one twelfthun!ia. An in!h is one8twelfth of a
foot and an oun!e is one twelfth of a pound. ell, sometimes.
4t!ould also "e one si(teenth, "ut that9s not the origin of the
word. 4 think what9s really going on isthat in the olden days the
world for twelfth was used indis!riminately for all sorts of small
fra!tionswith very little regard for mathemati!al !onsisten!y. 4
think they had other things to worry a"out.
POUND
:ound !omes from atin pondus for weight. The a""reviation l" for
pound !omes from the ;omanunit li"ra 'a"out three8quarters of an
%nglish pound), whi!h !omes from the atin li"ro, to weigh. Avariant
sym"ol had a "ar drawn through the as!enders like this . 4n !ursive
form, the sym"ol wasredu!ed to two verti!al and two hori$ l"s!heese
>6 l"shemp @$ l"sThe word stone is "oth the singular and plural
form of the unit 'one stone, two stone, three stone).
HUNDREDWEIGHTogi!ally, a hundredweight should "e a hundred of
something # a hundred pounds would "e myedu!ated guess. This was
the !hoi!e made in %ngland way, way "a!k and adopted "y the
nited3tates at its founding. But what if you prefer the stone over
the pound as your "asi! unit of weightCThis was the !ase in %ngland
soon after the Ameri!ans left the %mpire. The nearest multiple of
astone greater than a hundredweight is ? stone or >>$ pounds.
This "e!ame the new
hundredweight in %ngland. To distinguish "etween the two, the
original>00 pound hundredweight is !alled a short hundredweight
or a !ental while the newer >>$ poundhundredweight is !alled
a long hundredweight.
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TONThe origin of this word is the 1ld %nglish tunne # a "ig
!ontainer. Brewers are the last people whostill use this word 'mash
tun, lauter tun, fermentation tun). ater the word also !ame to mean
the!apa!ity of su!h a !ontainer and was used as a unit of "oth
volume and weight. The volume unitwas not as popular as the weight
unit e(!ept in the railroad and shipping industries. %ventually
itwas de!ided that a ton would "e a good name for two thousand
pounds, sin!e that9s a"out theweight of water that a tun !ould
hold. hen the hundredweight !hanged in %ngland, so too did the
ton. Ameri!a kept the unit at $000 pounds while the %nglish
!hanged the unit to $$&0 pounds.'$$&0 pounds is >60
stone,"y the way.) As with the hundredweight, the Ameri!an ton is
!alled a short ton while the %nglish tonis !alled a long ton. The
similarly si000 kg is !alled a tonne in %ngland or a metri!ton in
the nited 3tates. To misquote *eorge Bernard 3haw, %ngland and
Ameri!a are two!ountries divided "y a !ommon unit system.
