﻿74 Scientific Intelligence. 



line, but by a curve, or generally by a series of curves. (2) 

 Each of these curves probably indicates the formation and exist- 

 ence of some fresh hydrate in the solution. (3) The formation of 

 higher hydrates as the temperature rises would not appear to 

 hold good when we approach a temperature which is near the 

 melting point of the solid hydrated salt, as in the case of sodium 

 sulphate. (4) From the constant variations in the thermal phe- 

 nomena attending dissolution at different temperatures, it follows 

 that the specific heats of saline solutions exhibit similar variations, 

 remaining constant, or even varying at a uniform rate, through- 

 out very limited ranges only. (5) The heat of combination of a 

 salt with its water of crystallization in the solid state undergoes 

 similar series of changes. (6) From this it follows that the 

 specific heat of such a salt is not a constant quantity, and that it 

 is not exactly equal to the sum of that of the anhydrous salt and 

 the solid water present, but is generally somewhat less. (7) The 

 general tendency between 2° and 23° is toward an increase of the 

 energy with which the water is combined. (8) Any temperature 

 at which a higher hydrate is formed by a salt in solution is 

 marked by a decrease in the heat of combination of the salt with 

 its water of crystallization in the solid state. (9) The heat of 

 combination of two sulphates to form a double salt is subject to 

 variations of the same nature as that of the combination of a salt 

 with water. (10) The variations in the heat of combination of 

 the two salts is attended by variations of an opposite sign in the 

 heat of combination of the double salt and the water combined 

 with it. (11) Most of the salts here investigated show some 

 points of similarity in the curves which they yield, but each pos- 

 sesses specific peculiarities. (12) The peculiarities exhibited by 

 a single salt appear to be reproduced to a certain extent in the 

 double salts which they form, — illustrated by the rise in the curves 

 of both the magnesium salts at about 22* and the character of 

 abruptness displayed in the case of both the copper salts." — J. 

 Chem. Soc, xlix, 260-311, May, 1886. g. f. b. 



3. On the Hypochlorites of Ethyl and Methyl. — Some time ago 

 in a preliminary paper, Sandmeyer showed that by mixing alco- 

 hol with strong aqueous hypochlorous acid, hypochlorous ether 

 was separated as a yellow oil. The ready decomposition of the 

 acid, however, caused the yield to be very small. The author 

 now finds that almost the theoretical quantity can be obtained if 

 the alcohol be mixed with caustic soda solution and chlorine gas 

 be passed through the liquid, well cooled. For this purpose, a 

 glass tube 3 cm in diameter and 40 cm long, drawn to a narrow neck 

 at top and. having a glass stopcock at bottom, placed in a Liebig 

 condenser, was three-quarters filled with a solution of one part 

 sodium hydrate and one part alcohol in nine parts of water, and, 

 being slightly inclined from the horizontal, chlorine gas Avas 

 passed in through the stopcock, the whole being cooled by a cur- 

 rent of water. The gas was readily absorbed, the solution be- 

 came yellow and turbid and a layer of yellow oil collected on the 



