BETWEEN THE VISCOSITY OF LIQUIDS AND THEIR CHEMICAL NATURE. 677 
sulphur, which, employing the ordinary values for carbon and hydrogen, apparently 
has the value 
II 
S = 1(241 - 148) = 47. 
The values thus obtained for sulphur are related to one another in a similar way to 
those already given for ether oxygen and carbonyl oxygen. 
Molecular viscosity work. 
Molecular refraction. 
Oxygen. 
Sulphur. 
Oxygen. 
Singly-linked. 
39 
144 
1'655 
Doubly-linked. 
-19 
47 
2-328 
Difference. 
58 
97 
- -673 
Bruhl arrives at corresponding values in the case of oxygen from a study of mole¬ 
cular refraction ; his numbers are given in the last column of the above talde. In 
conformity with what has already been said, the difference in the case of molecular 
refraction is negative, while in the case of viscosity it is positive. 
Water. 
The observed value for water is 55. 
The calculated value, using the value for hydroxyl oxygen, and the ordinary value 
of hydrogen, is 30, so that tire observed number is twice as large as that calculated 
in this way. Having regard to the general physical behaviour of liquid water as 
indicating the existence of molecular aggregates, and also to the mode in which the 
fundamental constants were deduced, this difference is what might have been anticipated. 
The value for hydroxyl oxygen was deduced from the observed numbers given by the 
II 
acids on the assumption that in these liquids C, H, and O had the same values as in 
simply constituted liquids. Seeing, however, that the acids contain molecular 
aggregates, the value of '^0^ will be affected by this influence and cairnot, therefore, 
be expected to apply to liquids containing molecular aggregates which difier in 
complexity from those of the acids. 
The large difference obtained above may, in the main, be attributed to the fact that 
at equal slope the complexity of water is different from that of the acids, a conclusion 
which is supported by surface-energy observations. The fact also that in the simple 
water molecule OH is linked to hydrogen and not to- an imsaturated “ rest ” as in 
the simple molecule of an acid may also exert some eftect. 
