BETWEEN THE VISCOSITY OF LIQUIDS AND THEIR CHEMICAL NATURE. 701 
Isomeric Ketones. 
t'. 
Difference. 
Diethyl ketone. 
Methyl propyl ketone .... 
o 
50-5 
56'5 
O 
6-0 
Of the two ketones, the symmetrical compound has slightly the lower temperature. 
Here, as in the case of all other comparisons, the chlorethanes differ from the 
ketones. 
Temperatures = t" in degrees Centigrade at which the Slope is -0000987. 
At slope -O^OSf the temperature differences obtained on making comparisons of the 
kind given in the preceding tables are practically of the same order as are there 
represented. This result follows from the fact that the ratios of the absolute tem¬ 
peratures of the two slopes are practically constant. 
The mean value of the ratio, 
Absolute temperature at slope •04,323 
Absolute temperature at slope 'O^OS? 
for the thirty-four possible comparisons is 1-23, the average divergence from the 
mean being '017, or about 1-4 per cent. It is also worthy of note that the liquids 
giving the largest divergences were water, benzene, and formic acid ; the differences 
were all negative, and about 5-7 per cent, in the case of water, amd 3-3 per cent, in 
the case of the other two liquids. 
That the temperature differences are of the same order at any slope was also 
verified by comparisons made at various slopes which are not discussed in this paper. 
It now remains to examine how the temperatures gi\^en by the alcohols at slope 
0^987 are related to one another. The results are expressed in the following tables :— 
