Ixxvi GENERAL SUMMARY OF SCIENTIFIC AND 



posure to the air, consisted of 35 per cent, of soluble matter, 9 of wa- 

 ter, 22 of carbon, 18 of carbonate and oxysuliDhide of calcium, ashes 

 and iron oxide, 15.4. The soluble portion contained 11.9 caustic 

 soda, 44.30 carbonate, 24.10 sulphate, 11.70 suli^hite, 0.45 sulphide, 

 7.05 chloride of sodium, 0.2 silica, 0.3 of alumina, and traces of lime 

 and potash. 



Terrell has analyzed the black residue obtained by calcining po- 

 tassium ferrocyanide, and finds it to consist of metallic iron, 32.05 ; 

 magnetic oxide of iron, 27.56 ; uncombined carbon, 27,49 ; combined 

 carbon, 1.17; carbon as cyanogen, 0.24 ; potassium, 0.81 ; nitrogen, 

 0.29 ; oxygen, 10.50. 



Griinzweig and Hoffmann have conclusively sustained their state- 

 ment of the crystalline character of ultramarine, against Buchner, 

 who had maintained that the crystals observed under the micro- 

 scope were those of quartz. They now bring forward the testi- 

 mony of additional experts, who have seen and examined the crys- 

 tals, and of Vogelsang, who has determined them to belong to the 

 cubic system. 



Gladstone has observed that the chemical activity of aluminum is 

 greatly augmented by contact with a more negative metal, this sub- 

 stance decomposing water readily at 100 Centigrade when either 

 copper or platinum was electrically deposited uj)on it. In connec- 

 tion with Tribe, Gladstone has also made some experiments upon 

 the activity of pure zinc, as compared wdth zinc ui)on the surface of 

 Avhich copper has been deposited. From this it appears that even 

 arsenical zinc, when covered with copper, may be boiled with water, 

 and evolve large quantities of hydrogen without giving in this gas 

 a trace of arsenic. The foil alone, treated with dilute sulphuric 

 acid, gave abundance of arsenous hydride. 



Gladstone and Tribe have also extended their researches to the 

 decomposition of aluminum in presence of its haloid comiDOunds, 

 and have observed that alcohol is readily decomposed on heating 

 with this metal and its iodide, evolving hydrogen and leaving alu- 

 minic ethylate in the retort. This latter body is a yellowish-white 

 solid, which is capable of distillation. 



Naumann shows that potassium-alum solutions, when heated to 

 100 Centigrade, are partially decomjjosed, losing a portion of their 

 sulphuric acid. 



Troost and Hautefeuille have described a manganese boride, and 

 have studied elaborately the part which manganese j^lays in the 

 metallurgy of iron, paying especial attention to the thermo-chem- 

 ical reactions involved. 



Parsons has made a series of experiments at the "Woolwich Foun- 

 dry on a manganese bronze, which, when forged, had a strength of 

 twenty-nine tons to the square inch, an elastic limit of twelve tons, 

 and an elongation of nearly thirty-two per cent. 



