INDUSTRIAL PROGRESS DURING THE YEAR 1874. x lv 



nature of polymerism ; and it can not be definitely settled 

 until some method is devised for determining the molecular 

 weight of non-volatile compounds. An important step in this 

 direction has been taken by F.W.Clarke, who has shown 

 that the molecular volume of chemically combined water is 

 variable, while that of crystal-water, or molecularly united wa- 

 ter, is invariable. The researches of Berthelot upon Thermo- 

 chemistry ', actively continued during 1874, will no doubt con- 

 duct finally to the same desirable end. 



In Inorganic Chemistry, Troost and Hautefeuille have shown 

 that palladium forms a definite compound with COO volumes 

 of hydrogen, Pd 2 H, and that then this may itself dissolve ad- 

 ditional hydrogen. They have also prepared the compounds 

 Na 2 H and K 2 H, and have observed that both lithium and 

 thallium have a feeble occluding power for hydrogen. They 

 calculate the density of hydrogenium in the solid form as 

 0.63. Bottger, following in the same line, describes some 

 interesting experiments with the palladium alloy, and shows 

 that hydrogen is absorbed likewise by nickel, cobalt, and 

 tin. F. Wohler states, too, that palladious oxide, produced 

 from the nitrate by ignition, is reduced by hydrogen even in 

 the cold, with incandescence. Tribe calls attention to the 

 curious property of agglomerating finely divided metals 

 possessed by hydrogen. 



Mermet proposes the action of hydrochloric acid upon chlo- 

 ride of lime in the cold as a ready means of obtaining chlo- 

 rine. The chloride is placed in a self-regulating apparatus, 

 like that used for hydrogen or carbonic acid. A. Kaumann 

 has discovered the important fact that in metameric organic 

 bodies containing oxygen, of the same chemical character 

 and similar in structure, the boiling-point is lower the near- 

 er this oxygen approaches the middle of the atomic chain. 

 Schrotter has analyzed a cosmetic for turning the hair to a 

 golden color, and finds it to be a dilute solution of hydrogen 

 peroxide, containing about six times its volume of oxygen. 



Kingzett has thoroughly investigated the alleged produc- 

 tion of ozone by the oxidation of essential oils in sunlight, and 

 lias shown that neither ozone nor peroxide of hydrogen is 

 formed, but that the activity of the oil is due to a peculiar 

 compound, probably hydrate of terpene oxide. Schone shows 

 (1) that a loss of one-quarter part of ozone takes place when 



3 



