Dr. Wilhelm von Bezold on Twilight, 419 



was slowly corroded, and iodide of silver was decomposed and 

 its iodine set free. 



Anhydrous carbonate of copper was slowly blackened by contact 

 with metallic arsenic in powder beneath bisulphide of carbon. 



Remarks. 



Bisulphide of carbon dissolves metalloids only, viz. phos- 

 phorus, sulphur, selenium, bromine, and iodine; metals tend 

 only to remove its sulphur. It dissolves the chlorides, bro- 

 mides, and iodides [of phosphorus, arsenic, and antimony, 

 generally with facility, those of phosphorus and arsenic (espe- 

 cially the chlorides and bromides) the most readily. It dissolves 

 also, with varied degrees of facility, the chlorides, bromides, and 

 iodides of sulphur and selenium. Persulphide of hydrogen is 

 freely soluble in it. It also mixes freely with the bichlorides of 

 titanium and tin. Metallic oxides, fluorides, chlorides, bro- 

 mides, iodides, and sulphides, and the whole series of oxygen 

 salts, including carbonates, borates, hypophosphites, phosphites, 

 phosphates, sulphates, sulphites, hyposulphites, chlorates, bro- 

 mates, iodates, and nitrates, are insoluble in it. 



The solution of phosphorus in bisulphide of carbon may be 

 considered as a deoxidizing liquid, as shown by its action upon 

 sulphuric acid, molybdic acid, and chromic acid, and especially by 

 its behaviour with the various oxygen salts of copper. And the 

 solutions of bromine and iodine may be v : ewed as oxidizing 

 liquids, being decolorized chiefly by deoxidizing substances, 

 such as metals, sulphides, sulphites, hyposulphites, &c. By 

 means of these solutions of opposite chemical character, nu- 

 merous chemical reactions may be obtained, as already shown. 

 Various sulphides might also probably be formed by means of 

 the solution of sulphuretted hydrogen or persulphide of hydro- 

 gen in bisulphide of carbon. 



My intention in the foregoing paper being merely to show 

 that numerous chemical reactions might be obtained by em- 

 ploying anhydrous liquids as solvents, I have refrained from 

 further examining the special reactions obtained. 



LXI. On Twilight. By Dr. Wilhelm von Bezold*. 



I TAKE the liberty of communicating in the following pages 

 the principal results of an investigation which I published 

 in detail some little time ago in PoggendorfF 's Annalenf. It 



* Communicated by the Author, 

 t Vol. cxviii. pp. 240 & 276. 



