LONDON Chemical Society, January 20.—Prof, H. E. Roscoe, president, in the chair.—The president announced that the Faraday lecture would be delivered by Prof. Helmholtz in the Royal Institution, On the Modern Development of Faraday's Concep tion of Electricity. The following papers were read:—On pentathionic acid, by Mr. V. Lewes. The author has succeeded in obtaining beautifully crystallised barium and potassium pentathionates by partially neutralising Wackenroder's solution and evaporation in vacua.—A preliminary note on some hydrocarbons from rosin spirit, by Dr. Armstrong. Cymene, toluene, and metaxylene were found to be present. The hydrocarbons in soluble in sulphuric acid are probably hexhydrides of hydro carbons of the benzene series. The author does not consider that rosin is directly derived from terpene.—On the determi nation of the relative weight of single molecules, by Dr. Vogel of San Francisco.—On the synthetical production of ammonia by the combination of hydrogen and nitrogen in presence of heated spongy platinum, by G. S. Johnson. About 0.0144 grm. of ammonia were obtained in two and a half hours.—Gn the oxidation of organic matter in water, by A. Downes.—Analyses of Queensland soils, by Prof. A. Liversidge. These analyses are interesting, as the soils include samples from districts which were exempt from the disease prevalent in the sugar plantations around.—On the volumes of some compounds of the benzene naphthalene, anthracene, and phenanthrene series, by Dr. Ramsay.—On the atomic volume of nitrogen, by Dr. Ramsay.—On a new theory of the conversion of bar iron into steel by the cementation process, by Dr. Marsden. The author thinks that carbon diffuses hi an impalpable powder through the heated iron.—On the action of sulphydrate of potassium on chloral hydrate, by W. W. J. Nicol. Thioglyoxylic and thioformic acids are formed.