INDUSTRIAL PROGRESS DURING THE YEAR 187G. ]xxi 



bismuth chloride, to which various quantities of water were added, 

 the amount being in all cases more than enough to f)roduce the 

 precipitate. These precipitates were analyzed, and the ratios of the 

 chlorine and bismuth determined. From them a curve was con- 

 structed, which is hyperbolic along two thirds, and straight for the 

 other third of its length. Hence the author believes Bertholiet's law 

 is true, the action being proportional to the mass, the curve being 

 due to external influences, 



INORGANIC CHEMISTRY. 



Pierre and Puchot have obtained a crystallized hydrate of hydro- 

 chloric acid by cooling a saturated solution of the gas in water to 

 21 or 22 Centigrade, a current of this gas being maintained 

 through it. As soon as crystallization begins, the temperature rises 

 to 18, and remains there so long as crystals form. Synthetical 

 calculation as well as analysis fixed the formula of the crystals as 

 HC1(H20)2. The authors hence recommend a mixture of hydrochlo- 

 ric acicl and snow as a freezing mixture. 



Berthelot has studied the thermic conditions attending the for- 

 mation of ozone. He finds that in the production of one molecule 

 of ozone from oxygen there is an absorption of 29,6 calories. 

 Being therefore a body formed with the absorption of heat, its activ- 

 ity chemically is accounted for ; it is a magazine of energy stored up 

 under the influence of electricity. 



Frankland has published a paper on water analysis, in which he 

 examines the value of the albuminoid-ammonia process, and con- 

 cludes tliat it is " entirely useless in the examination of waters for 

 sanitary purposes." He claims, however, for the combustion process, 

 that it is the only one which gives trustworthy information concern- 

 ing the organic matter present, tlie only one which can determine the 

 carbon, and the only one which shows the ratio of nitrogen and 

 carbon. 



Gladstone and Tribe have shown that water may be decomposed 

 by the joint action of aluminum and aluminum iodide, bromide, or 

 chloride. They suggest as probable that the reaction takes place in 

 two stages. In the first the aluminum of the iodide is oxidized, 

 and in the second it is regenerated, setting free hydrogen, 



Precht and Kraut have pul)lished the results of experiments made 

 to test the statement of Debray that the tension of aqueous vapor 

 which is given by a salt containing crystal-water in a vacuum is de- 

 pendent solely upon the temperature, and hence that this tension 

 may be made use of to ascertain whether all the molecules of this 

 water of crystallization are held with equal force. Their conclusion 

 is that while in individual cases this may be done, it can only be 

 considered reliable when all the collateral circumstances are taken 

 into the account. 



