13G ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



of moisture. As to the diamond, the author thinks that this 

 mineral is the result of the action of reducing agents upon 

 very highly compressed carbon dioxide at temperatures 

 above its critical point a condition of things which sug- 

 gests a new direction for speculation and experiment. 



Zoiler has recommended the vapor of carbon disulphide 

 as an antiseptic agent. Prepared from potassium xanthate, 

 its odor is but trifling. Experiments show that five grams 

 of this liquid volatilized in a space of about one seventh of a 

 cubic meter will preserve twenty kilograms of meat placed 

 in this space for from two to three weeks. 



METALLIC. 



Jean has proposed a method of titrition for the suljmates 

 of the alkalies, which is as follows: The aqueous solution of 

 the sulphate is treated first with baryta water in excess, 

 then with carbonic -acid water decanted from the mixed 

 precipitate of barium sulphate and carbonate, the liquid 

 boiled, the whole filtered, the precipitate washed out, the 

 filtrate and washings concentrated and titered as usual with 

 a standard sulphuric acid. From the quantity of free alkali 

 carbonate present, the quantity of sulphate originally united 

 to it is known, being the exact quantity employed in neu- 

 tralizing the alkaline filtrate. 



Johnson has prepared potassium tri-iodide, by evaporat- 

 ing over sulphuric acid a saturated solution of iodine in po- 

 tassium iodide. At first dark-colored cubical crvstals of the 



r 



iodide, colored by iodine, were deposited ; but in a few days 

 lustrous dark-blue prismatic crystals, sometimes two inches 

 long, separated, which had the composition of the tri-iodide, 

 and were extremely deliquescent. Their specific gravity 

 was 3.498. 



Frey has given the details of the manufacture of the al- 

 kali-earth metals in Gorlitz which were exhibited in Lon- 

 don and Philadelphia. In general the electrolytic method 

 of Bunsen is closely followed, the current being weaker. 

 From two and a half to four grams were produced at each 

 operation. Calcium is not yellow, but resembles aluminum 

 closely, being brittle like it, and not being malleable or te- 

 nacious. Strontium is bright brass-yellow, very malleable, 

 easily rolled and drawn, and oxidizes much easier than cal- 



