806 REPORTS ON THE STATE OF SCIENCE.—1912. IIL.s. 
Further addition to the knowledge of solubility of substances in 
solvents other than water was made by McIntosh, Archibald, and 
Steele,*** who examined the solubility of organic and inorganic sub- 
stances in hydrogen halides. With the object of throwing light upon 
the relationship between solvent and .solute, Walden *** compared 
the solubilities of a number of tetralkyl ammonium halides in different 
solvents. In the case of tetramethyl-ammonium iodide he found that 
the solvent power was greatest in the case of solvents containing 
hydroxyl groups and increased with (1) the associative power and 
(2) the dielectric constant of the solvent. 
1907 The question of the solubility of d- and l-isomerides in opti- 
‘ eally active solvents again received attention, this time from 
Jones,*°* who found the solubility of the isomerides in active solvents 
to be identical with the solubility in inactive solvents. In continuation 
of his work upon the properties of liquid ammonia as a solvent, 
Kraus *°° examined the solubility of the alkali metals in this liquid and 
also in alkylamines. The metals are only soluble in methyl- and in 
ethyl-amine, not in the higher members of the series. Shinn ?** also 
determined the solubility of a number of salts in ethylamine, finding the 
most soluble to be silver nitrate, lithium chloride, and ammonium 
chloride. 
Magri *'* found that although liquid sulphuretted hydrogen does not 
dissolve salts of strong bases, it is a good solvent of compounds of non- 
metals amongst themselves, such as sulphur iodide. 
Van Laar**? deduced the following general expression for the 
solubility of any electrolyte in any solvent: c=CA (1+A), in which ¢ 
represents concentration in the saturated solution, C the dissociation 
constant, and A a constant almost independent of the nature of the 
1908 solvent. Acetamide was compared with water as a solvent by 
*  Menschutkin **°; he found a close similarity to exist between 
these two solvents: many salts crystallise with acetamide of crystallisa- 
tion, and there is a close correspondence between the solubility curves 
of the hydrates and of the compounds with acetamide. Comparing the 
solubility of tetraethyl ammonium iodide in water and in a number of 
organic solvents, Walden *** found that if the saturated solution con- 
tained n molecules of solute for every N molecules of solvent, then, if 
S represents the solubility, the following relationship obtained :— 
He also found that the cube root of the solubility of tetraethyl am- 
monium iodide in any solvent is nearly proportional to the dielectric 
constant of the solvent. 
Herz and Kuhn **7 compared the solubility of various haloid salts 
of mercury, potassium, sodium, and ammonium in different alcohols, 
and found that the solubility diminishes as the molecular weight of the 
alcohol increases. 
1910 Dolezalek *7® concluded, on purely theoretical grounds,* that 
’ the ratio of the solubility of two indifferent gases should be the 
* Vide Section IV. A. 
