CHEMISTRY. 655 



IfjOs along with N2O4, both in a state of gas. 3. In the presence of 

 water nitric oxide with an excess of oxygen is altogether converted 

 into HNO3. 4. If nitric oxide and oxygen meet in the presence of con- 

 centrated sulphuric acid there is neither N2O4 nor HNO3 formed, even 

 with the greatest excess of oxygen, but the reaction is — 



2H2S04+2NO+0=2S02(OH)(ONO)+H80 ; 



that is, nitrosyl sulphate and water. 



This last reaction has an important bearing on the theory of the 

 manufacture of sulphuric acid. The author maintains that it is not, as 

 generally assumed, the nitric oxide, NO, but the nitrogen trioxide, NaOs, 

 which acts as the carrii^r of oxygen in the vitriol-chamber process. {J. 

 Chem. Soc, London, July, 1885, p. 465.) 



On the Enaction between Mercurous Nitrate and Nitric Oxide, and heticeen 

 Mercurous Nitrate and Nitrites (by Dr. Edward Divers and Tamemasa 

 Haga). — It has been known for, perhaps, half a century that mercurous 

 nitrate yields metallic mercury when treated with a solution of alkaline 

 nitrite, and this reaction has always been regarded as one of oxidation 

 of the nitrate by reduction of the mercury salt. The authors show this 

 is incorrect. When, with exclusion of air, pure nitric oxide is passed 

 into a solution of mercurous nitrate in dilute nitric acid, a precipitation 

 of metallic mercury slowly takes place and hydroxyamine is formed in 

 quantity, but no ammonia. Prolonged contact of the gas gives rise to 

 beautiful long yellow i)risms, while the hydroxyamine disappears from 

 the mother liquor. This new yellow salt will be more fully described 

 by the authors at a later date. The first stage of the reaction is thus 

 formulated by these chemists : 



(HgN03)2-f2¥0=2(NO)N03+2Hg, 



* 



nitric oxide precipitating mercury from its salt. The nitrosyl nitrate, 

 here assumed to form, will at once decompose with water and mercurous 

 nitrate into hydroxyammonium nitrate and mercuric nitrate, thus : 



4(HgN03)2+8HN03+2(NO)N03=8Hg(N03)2+2(HO^^H3)N03. 



An after reaction between mercuric nitrate and the nitric oxide follows, 

 and the hydroxyamine is decomposed. {Chem. News, lii, 8.) 



The Sulphur Compounds of Calcium (by V. H. Veley). — The main points 

 in this paper are thus summarized by the author: 



1. By the action of hydrogen sulphide on solid calcium hydroxide 

 there is formed a calcium monosulphide, in accordance with the equa- 

 tion: 



Ca(On)2+H2S-CaS+2H20. 



2. By the action of hydrogen sulphide on calcium hydroxide in aque- 

 ous solution there is formed calcium hydrosulphide, in accordance with 

 the equation : 



Ca(OH)24-2H2S+a;Aq=Ca(SH)2+20H2-f.rAq. 



