— 207 — 
TABLE XV. 
Mercury, gt = 4” T = 21.3 C. Radius of sphere = 12.8, 
gms. 
10, Principal drops weighed 6.3447 
10, 1st supplementary „ 0.1242 
10, 2nd „ „ 0.0229 
10 complete drops weighed . . 6.4918 
In all cases the supplementary drop or drops were collected 
and weighed or measured with the main drop. 
In the Table XVI. 
Column 1 shows the medium through which the mercury 
dropped. 
Column 2. The number of drops weighed. 
Column 3. The weight of the drops. The weight of every 
batch of drops is given in order that the approximation be- 
tween the figures for each liquid may be compared with that 
between the separate liquids. In two cases, only, marked by 
an asterisk are the numbers probably erroneous. They are 
not reckoned in taking the mean. 
Column 4. Mean weight of single drop, from column 3. 
Column 5. Specific gravity of medium. 
Column 6 shows the weight of the drop of mercury in the li- 
quid. Since the falling of the drop is determinated in part by its 
weight and since the weight depends not only upon the size of the 
drop, but also upon the density of the medium in which it is 
found it is interesting toseehow the size ofthe drop is affected by 
the diminutionin its weight causedbythe density ofthe medium. 
If W =weight of drop of mercury in air. 
W 2 = required weight of drop of mercury in liquid. 
A = Specific gravity of liquid. 
B = Specific gravity of mercury. 
then W 2 = Wi — ~ Wi . 
The values of W 2 form column 6. 
The liquid medium are arranged according to the order of 
magnitude of the number of column 4. 
