INDUSTRIAL PROGRESS DURING THE YEAR 1874. \{ 



charge. According to Berthelot, the solid body is polymerized 

 acetylene. C. R. A.Wright has continued his researches upon 

 the isomeric hydrocarbons of the terpene series, and has 

 made considerable progress toward determining the nature 

 of their isomerism. Riban has also been working industri- 

 ously in this direction, and with success. Groves has sug- 

 gested a ready method of preparing ethyl chloride, by dis- 

 solvino- zinc chloride in twice its weight of alcohol, and 

 passing a current of hydrochloric acid into the solution at 

 a boiling temperature. The chlorides of the other alcohol 

 radicals may be prepared similarly. Hofmann has continued 

 his researches into the constitution of essential oils. He has 

 proved that the oil of Cochlearia officinalis, the so-called 

 scurvy-grass, is the iso-sulphocyanate of secondary butyl al- 

 cohol ; the oil of Tropceolum majus, the common nasturtium, 

 the nitrile of a-toluic (phenyl-acetic) acid; the oil of Nastur- 

 tium officinale, the ordinary water-cress, is the nitrile of 

 phenyl-propionic acid, and a homologue of the former; the 

 oil of Lepidium sativum, the cultivated pepper -grass, the 

 nitrile of phenyl-acetic acid, and identical with that of Tro- 

 pceolum majus. Gladstone and Tribe have studied the action 

 of their copper-zinc couple being granulated or laminated 

 zinc upon which copper has been deposited by immersion 

 in a dilute solution of copper sulphate upon the bromides 

 and iodides of some of the alcohol radicals and the olefines, 

 both alone and in presence of water and alcohol. 



An exhaustive paper has appeared, by Victor Meyer, upon 

 the nitro-compounds of the fatty series. These bodies are iso- 

 meric with the corresponding nitrous ethers nitro-ethane 

 C 2 H 5 N0 2 being isomeric with ethyl nitrite C 2 H 5 O NO 

 but are distinguished from them by the fact that, like the 

 nitro-derivatives of the aromatic series, they are capable of 

 reduction to amines nitro-ethane, for example, becoming 

 ethylamine C 2 H 5 NH 2 . Ladenburg has added many more 

 substances to the list of those interesting organic compounds 

 in which silicon replaces carbon. He has described the 

 methyl ether of silico-propionic acid, prepared by the action 

 of zinc ethyl upon methyl orthosilicate, silico-acetic acid, pre- 

 pared analogously, the chloride of silico-phenyl, ethyl-ortho- 

 silico-benzoate, and meta-silico-benzoate, meta-silico-benzoic 

 oxide, silico-phenyl-triethyl, the chloride of silico-tolyl and sil- 



