LX PHILOSOPHICAL SOCIETY OF WASHINGTON. 
The metric standard of weight, called a kilogram, was constructed 
under the direction of the French Academy of Sciences simulta¬ 
neously with the meter; the work being done principally by Lefevre- 
Gineau and Borda. It was intended that the kilogram should have 
the same mass as a cubic decimeter of pure water at maximum 
density, and the experimental determination of that mass was made 
by finding the difference of weight in air and in water of a hollow 
brass cylinder whose exterior dimensions at a temperature of 17*6° 
C. were, height = 2*437672 decimeters, diameter = 2’428368 deci¬ 
meters, volume = 11*2900054 cubic decimeters. The difference of 
weight in question was first measured in terms of certain brass 
weights, by the aid of which the platinum kilogram of the archives 
was subsequently constructed, special care being taken to apply the 
corrections necessary to reduce all the weighings to what they 
would have been if made in a vacuum.^ 
The best results hitherto obtained for the weight of a cubic deci¬ 
meter of water, expressed in terms of the kilogram of the archives, 
are as follows: ^ 
Date. 
Country. 
Observer. 
Weight of 
a cubic 
decimeter 
0 f water 
at 4° C. 
1795_ 
Frn.nne 
Tififfivrp-rrinean 
Grams. 
1000-000 
1797—1 
England_ 
Shuckburgh and Kater _ __ 
1000-480 
1821__J 
1825_ 
Sweden_ 
Berzelius, Svanberg, and Akermann_ 
1000-296 
1830_ 
Austria_ 
Stampfer___ __ _ _ _ _ 
999-653 
1841_ 
Russia _ 
KnpfFp.r 
999-989 
Mean __ .. - 
1000-084 
^ Base du Systeme Metrique, T. 3, pp. 574-5. 
2 This table has been deduced from the data given by Prof. Miller in 40, 
p. 760. 
