s 
2 ‘London: Macmillan & Co., 1875. 
£2 * The West American Scientist. 
which the number 12 !ends itself to binary division up to a certain 
point, which makes it popular with all classes who have to deal 
with one another in the disposal of quantities in small number. 
The English pound weight was originally the weight of 7680 
grains of wheat, all taken from the middle of the ear and _ well 
dried ,* The division into sixteen ounces is again an example of 
the binary division of the unit in preference to that of the decimal. 
Any change from the authorized standards of length, surface 
and weight would fall most heavily upon the manufacturing com- 
munity, Bars of iron and multitudes of other commercial com- 
_ modities are made in certain definite sizes, and advance by regular 
fractions of the inch, These sizes if expressed in metric decimals 
would b2 exceedingly awaward to use, If articles were made 
to fractions of the metre, it would necesitate similar changes in 
the calculations and requirements of the consumer. The mech- 
 anical equivalents, such as the weil known foot, pound, and the 
___ horse power, (33,000 pounds raised one foot high iz one minute,) 
: _ wou'd disappear and the gram-centimetre, or some such standard 
_ to indicate pressure acting through space—the mathematical con- 
_ ception of work,—would take the place of these. 
The fact of the incorrectness, from a scientific point of view, 
which to deduce the metre, has very little weight with most peo- 
ple, It is now a question whether the already devised and ex- - 
The metre+ as defined is 39,47 British or United States inches. 
‘Iti is divided into ten equal parts called decimetres; each 3.937 
inches long. | Kach decimetre is again divided into ten equal 
parts called centimetres, each 0.3937 inches long. Each centi- 
metre is divided into ten millimetres, each .03937 of an inch. The 
multiples of the metre ae first, the decametre, a distance made 
up of ten metres, and equal to 32.8 feet. The hectometre is 10 
-decametres or 100 metres, and measures 328.08 feet. The kylo- 
‘metre, 1000 metres, equals 1093.63 yards; and the myriometre 
made up of 10,000 metres is equal to 6.21 miles. The fractions 
of the metre, and indeed all the metrical fractions, use the Latin 
prefixes, while the multiples use the Greek. 
*Chamber’s Encyclopedia, London, 1860. 
tLessons in Elementary Chemistry by Henry E. Roscoe, B.A., F.R.S., 
