Abstract
Journal of the Chemical Society, October, 1870.—The first paper in this number is by Dr. Divers, “On the Precipitation of Solutions of Ammonium Carbonate, Sodium Carbonate, and Ammonium Carbamate by Calcium Chloride.” These results obtained by Dr. Divers are the following:—Calcic carbonate is soluble, and the presence of ammonia, retards its transformation into carbonate. When carbonic anhydride is passed into an ammoniacal solution of calcic chloride, the carbamate is first formed, and is gradually precipitated as carbamate. This paper is followed by nearly two pages of Addenda et Corrigenda to theauthor's previous memoir.—“On the Manipulation of Gold and Silver Bullion,” by Charles Tookey, Assayer in the Japanese Imperial Mint, formerly in the Royal Mint, Hong Kong. In this paper the author gives descriptions of two of the processes that he has adopted. Instead of boiling the cornets in separate parting flasks, he uses a series of perforated platinum tubes, supported in a porcelain plate. A number of cornets are, by this means, simultaneously submitted to the action of the nitric acid. Secondly, in order to clean the buttons, they are placed with the lower side uppermost on a platinum plate with depressed perforated cavities, which is plunged into hot dilute hydrochloric acid, afterwards into hot water acidulated with hydrochloric acid, and lastly into pure water. The plate is then drained by placing it on porous paper and dried over a g s flame.—“On some new Bromine Derivatives of Coumann,“ by W. H. Perkin, F. R. S. On adding coumarin to bromine in the presence of carbonic disulphide, allowing the solution to evaporate, and crystallising the residue from alcohol, dibromide of coumarin C9H6O2,Br2 is obtained. When coumarin and bromine in carbonic disulphide are digested at 140°, bromo-coumarine C9H5BrO2 and dibromo-coumarin C9H4BrO2 are produced, and are separated by crystallisation from alcohol, in which the latter is the less soluble. Dibromo-coumarin fuses at 174°, and distils nearly unchanged. It crystallises from alcohol in small needles. Bromo-coumarin fuses at 110°, and crystallises from alcohol in transparent prisms, often beautifully curved. When heated with solution of potassic hydrate both the bromo-compounds dissolve, producing crystalline salts, probably containing the bromo-coumaric acids.—”On Organic Matter in Water,“ by Mr. C. Heisch. The author has observed that certain waters which are known to be contaminated with sewage matters, give rise to the formation of a microscopical fungus when a small quantity of sugar has been added, and the mixture exposed to light for a few days at the temperature of 60°–70° F. Six drops of sewage from which the solid matter had settled, were mixed with 10,000 grains of West Middlesex and New River water; to 6 oz. of the mixture 10 grains of pure sugar were added, and 10 grains were also added to 6 oz. of the water without sewage; these solutions, and some of the mixture of water and sewage, were placed at a window. The water containing the sewage and sugar became turbid in 24 hours, the other liquids remaining clear. On examining the turbid water with an 1/8 inch object glass, it was found to be filled with small spherical cells, with, in most cases, a very bright nucleus, which group themselves in bunches like grapes; they then spread into strings, with walls surrounding and connecting the cells; the original cell walls afterwards break, leaving tubular threads branched together. After several days, an odour of butyric acid is perceived. One drop of fresh urine in 10,000 grains of water produced similar effects; though without the addition of the sugar, the water might be kept for weeks without becoming turbid. Filtration through Sweaish paper, or boiling for half an hour, does not prevent the growth of the lungus. The water no longer exhibits this property, however, after passage through a good bed of animal charcoal, that is, if the charcoal is frequently exposed to the air. If the filtration is continuous, the filtrate soon becomes as bad as the original water. —“ On the Methods for the Determination of Carbon in Steel,” by Mr. W. D. Herman. The author has obtained very concordantresults by burning the iron or steel in a current of oxygen, the iron is converted into ferric oxide and the carbonic anhydride collected in potash bulbs and weighed. Some results obtained by four different methods of estimating the carbon in iron and steel are given at the conclusion of the paper.—“On the Determination of Phosphoric Acid,” by Mr. W. C. Williams. The author suggests a modification of the process for separating phosphoric acid from the alkaline earths originally proposed by Reigsig.
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Scientific Serials . Nature 3, 39–40 (1870). https://doi.org/10.1038/003039a0
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DOI: https://doi.org/10.1038/003039a0