CHEMISTRY. C37 



open shallow dish the liquid reached a temperature of — G° C. By for- 

 cing air over it the thermometer fell to — 19.5° C. {Am. Chcm. Journ., 



V, 15.) 



Blue Chloride of Sodium. — This ruineralogical curiosity occurs in small 

 quantity in the salt mines of Stassfurt and the cause of the hlue colora- 

 tion has been studied by B. Wittjen and H. Precht. As already no- 

 ticed by F. Bischof, the blue salt imparts no color to its aqueous solu- 

 tion; and the authors of this paper hud that no coloring matter can be 

 extracted by ether or by carbon disulphide. S. W. Johnson has sug- 

 gested that the blue color is due to sodium subchloride, but these au- 

 thors find that the color is not at all affected by heating the salt at 100° 

 C. in chlorine gas. They therefore conclude that the blue color is an 

 optical phenomenon. Pulverization aud heating to 280° C. destroys 

 the color, probably owing to the liberation of confined gases. (Ber. (L 

 client. Ges., xvi, 1454.) 



The Fluorine compounds of Uranium were made the subject of inves- 

 tigation in 1866 by H. Carrington Bolton. Ditte (Comptes rendus, 91) 

 afterwards prepared the same bodies and gave analytical data differ- 

 ing widely from those of Bolton. Arthur Smithells has now gone over 

 the same ground aud confirms the results previously obtained by Bol- 

 ton, and shows that the compounds claimed by Ditte have no existence. 

 (J.Ghem. Soc, March, 1883.) 



Xiirogen Selenide has been prepared by M. Verneuil, by acting on a 

 mixture of selenium perchloride and carbon dichloride with dry am- 

 monia gas. Its composition is Se 2 X, aud it forms a light orange amor- 

 phous powder, insoluble in water, ether, and alcohol, slightly soluble iu 

 benzene and carbon disulphide. When dry it detonates if struck with 

 a hard body, and explodes if heated to 230° C. (Bull. soc. chirn., 

 xxxvin, 548.) 



Occurrence of Thallium in Sylvite and Carnallite. — Julian Schramm 

 gives the following analysis of sylvite from Kalusz: 



Potassium chloride 99. 250 



Sodium chloride 0. 594 



Calcium chloride 0. 012 



Calcium sulphate 0. 143 



Thallium chloride traces. 



99. 999 



The author found thallium in carnallite and in kainite; in the former 

 it is associated with rubidium, but the latter contains neither rubidium 

 nor caesium. He thinks this association gives additional grounds for 

 classifying thallium with the alkali-metals: sodium, lithium and caesium 

 occur together on one hand, and potassium, rubidium, and thallium on 

 the other. (Liebig's Annalen, ccxix, 374.) 



