THE MASS OF A CUBIC INCH OF DISTILLED WATER. 
347 
As the weighings of the gravimeters were made against standard weights, which 
were parts and multiples of the Imperial Standard Pound, it became necessary, in 
order to find the true masses of the gravimeters, to reduce the weighings to a vacuum, 
as the Imperial Standard Pound itself has its true mass stated in vacuo. 
Weighing of C in water. 
Date, 1888. 
Weight of counter¬ 
poise (w -1 ). 
Mean t. water. 
Mean t. air. 
B. 
grains. 
O 
O 
in. 
Nov. 20 ... 
39091-84 
58-87 
56-0 
30-14 
„ 21 . . . . 
39109-85 
58-10 
57-2 
3015 
„ 22 . . . . 
39109-87 
56-38 
56-5 
30-22 
„ 24 . . . . 
39141-86 
61-42 
59"5 
30-30 
„ 27 . . . . 
39090-50 
57-61 
56-8 
29-38 
„ 29 . . . . 
39125-00 
58-00 
58-2 
29-34 
39111-49 
58-40 
57-37 
29-92 
The differences in the above weighings of C on the several days were considered to 
be owing partly to thermometric variations, and partly to the presence of minute 
bubbles of air 'carried down by this large cylindrical body. Results, however, could 
not be rejected merely because they did not always closely agree. 
At 32° Fahr., to which temperature densities are reduced : 
AC 32 o = 1-27029 
1 -27050 
1 -27061 
1-27055 
1-27036 
1-27064 
1-27049 
or log AC,a. = O'1040169. 
The logarithm of the volume of C in grains at 62° Fahr., may be expressed as 
follows :— 
Log vol. C = 5-1599338 
8626 
8272 
8476 
9102 
5-1598148 
or vC — 144499‘48 grains weight of water at 62° Fahr. 
