226 ANNUAL OF SCIENTIFIC DISCOVERT. 



covering the corks of vessels containing volatile substances (as 

 benzine, light petroleum, etc.) a mixture ofiinely ground litharge 

 and concentrated glycerine. Common glycerine, if concentrated, 

 will answer the purpose. 



Preparation of Nitrofjen. — A new and elegant method of pre- 

 paring this gas has been devised by Lev)", an Italian chemist. It 

 consists in ht-atinij^ bichromate of ammonium in a retort. The; salt 

 is transformed into green sesquioxide of chromium, and disen- 

 gages vapor of water and nitrogen. — Cosmos. 



Sulphurous Acid Jor Dissolving Bones. — It is well known that 

 hydrochloric acid is used for the purposes of dissolving the earthy 

 salts of bones, in order to obtain the gelatine in such a state as to 

 render that substance readily soluble in boiling water. Tlie use, 

 however, of hydrochloric acid is rendered rather inconvenient for 

 this pui'pose on account of the formation of chloride of caleium, 

 which interferes with the drying of the gelatine. M. Coignet, 

 at Paris, has found that sulphurous acid answers the purpose of 

 hydrochloric acid in this instance perfectly well. The bones are 

 placed in cold water, and through the water a current of sulphur- 

 ous acid gas is forced so long as is required to completely soften 

 the bones, which are afterwards washed in fresh water wherein 

 some sulphurous acid gas has been previously dissolved. — Drug- 

 gists'' Circular. 



Liquefied Hydrochloric Acid Oas. — In a paper read before the 

 Royal Societv, Mr. Gore gives the following summary : Out of 86 

 solids, liquefied hydrochloric acid gas only dissolved 12, and some 

 of those only in a minute degree; of 5 non-metallic sub-tances it 

 dissolved one, namely, iodine ; of 15 metals it dissolved only one, 

 namel}', aluminum ; of 22 oxides it dissolved 5, namely, titanic 

 acid, arsenious acid, arsenic acid, teroxideof antimony, and oxide 

 of zinc; of 9 carbonates it dissolved none; of 8 sulphides it dis- 

 solved one, namely, tersulphide of antimony ; of 7 chlorides it dis- 

 solved two, namely, pentachloride of phosphorus and protochloride 

 of tin ; and of 7 organic bodies it dissolved two. The results show 

 also that liquid hydrochloric acid in the anhydrous state manifests 

 much less chemical action upon solid bodies than the same acid 

 mixed with water, as under ordinary circumstances. — Abstract 

 oj" Proceedings of the Royal Society. 



Cyanogen in Coal Gas produced by Ammonia. — Romilly (^Erd- 

 mann's Journal filr Chemie, vol. 10.')) has shown that cj'anogen is 

 formed if illuminating gas is passed through weak water of am- 

 monia, and then the lighted burner is turned upon the surface of 

 a solution of a caustic alkali (potash, soda, or lime). After a 

 few minutes the j)resence of a cyanide can be shown in the alka- 

 line fluid by the iron test; and if the alkaline solution used was 

 strong potash lye, holding in suspension some line metallic iron, 

 th«*re will be produced bot^i ferro and ferri cyanide of potassium. 

 This happens only when the flame is bright from incandescent 

 carbon; that of a Bunsen burner (blue or colorless) is without 

 effect when directed on alkali after passing through ammonia, 

 the carbon being not free, but already oxidized. 



Black Phosjihorus. — M. Blondlot states that the production of 



