396 Chronicles of Science. [July, 



wasted. They name the bases of these colours Mauvaniline, Viola- 

 niline, and Chrysotoluidine. The methods by which these are 

 separated are described in the place indicated below.* The manu- 

 facture has been patented in France, and probably also in England. 



A new blue has also been patented in France, by the same 

 gentlemen. It is made by heating, under pressure, a mixture of 

 commercial aniline (aniline and toluidine) and hydrochlorate of the 

 same aniline with terchloride of carbon. The result is a bronze- 

 coloured mass, which is purified by first treating it with benzol or 

 petroleum, which will leave the dye undissolved ; then dissolving in 

 wood-spirit or alcohol, and finally precipitating with hydrochloric 

 acid. 



In connection with Technical Chemistry, we may mention a 

 paper of interest u On the Waste of Materials in the Alkali Manu- 

 facture," | by Mr. James Hargreaves. 



In this and the one mentioned subsequently in our report of 

 the proceedings of the Chemical Society, the alkali manufacturer 

 will find valuable information. 



A fact of much interest to the chemist and geologist observed 

 by M. Daubree deserves a passing notice. Felspar reduced to the 

 finest powder does not give the faintest alkalinity to water. But 

 M. Daubr.je finds that fragments of felspar violently agitated with 

 water will give up to the water as much as two per cent, of the 

 potash it may contain. The author sees in this an easy means of 

 obtaining an alkaline water for washing linen ; but at the same 

 time remarks that it mav throw some lisrht on the changes which 

 are taking place on the surface of our earth. 



Some important contributions to analytical chemistry have also 

 been made. A noteworthy paper, "On Pugh's Method of Deter- 

 mining Nitric Acid," has been published^ by MM. Chapman and 

 Schenck. 



This method, which has specially recommended for the deter- 

 mination of nitric acid in water, has been found by the authors to 

 be altogether faulty under the conditions in which it is likely to be 

 employed. The method will be well known to all our chemical 

 readers, and therefore we need only say, that in the presence of 

 nitrogenized organic matter, the authors have found it to be simply 

 valueless, inasmuch as such bodies as albumen, gelatine, and urea, 

 all yield ammonia when digested with protochloride of tin. 



Some analytical notes on Cadmium, by Wohler,§ give methods 

 of separating this metal from zinc and from copper. To separate 

 cadmium and zinc, the author adds a large excess of tartaric acid, 



* ' Bulletin de la Societe Chimique de Paris,' May, 1866. 

 t ' Cuemical News', vol. xv., pp. 219-232. 

 X ' The Laboratory,' Xo. 9. p. 152. 

 § • Chemical Xews, vol. xv.. p. 166. 



