CHEMISTRY. 



141 



in other, but not in alcohol and benzine. It 

 can be reduced to a liquid by means of Cail- 

 letet's apparatus. 



To the gaseous hydrates already known. M. 

 Yillard has added analogous hydrates of me- 

 thane, ethane, ethylene, acetylene, and protox- 

 ide of nitrogen. They are generally less 

 soluble and less easily liquefied than those 

 previously obtained, and are decomposable at 

 the respective temperatures of 2 1 '5, 12, 18'5, 

 14, and 12. all C. It is sho\vn in the case of 

 methane and ethylene that a gas may form a 

 hydrate above its criiical temperature of lique- 

 faction, and that these two gases have a 

 critical temperature of decomposition con- 

 siderably higher than the others. 



The gas, allene, the isomer of allylene, the 

 second member of the acetylene series of 

 hydrocarbons, has been obtained pure and 

 examined by MM. Gustavson and Demjanoff, 

 of Moscow. It is very different in some of its 

 properties from ordinary allylene, yet is repre- 

 sented by the same empirical formula, CH 4 . 

 It is obtained from the action of zinc-dust 

 upon an alcoholic solution of dibrom-propylene. 

 It is colorless, has a peculiar smell, and burns 

 with a smoky flame. Unlike allylene. it yields 

 no precipitate with ammoniacal copper or sil- 

 ver solutions, but gives white precipitates with 

 aqueous solutions of mercury salts. 



A sodium salt of zincic acid has been iso- 

 lated in the crystalline state by M. Comey, 

 and Loring Jackson, of Harvard University. 

 On shaking with alcohol a concentrated solu- 

 tion of zinc or zinc oxide in soda, the mixt- 

 ure separated on standing into two layers, a 

 header aqueous and a lighter alcoholic layer. 

 The heavier layer, being washed with alcohol 

 solidified with a mass of white crystals, while 

 the alcohol washings, on standing, deposited 

 long white crystals, which when purified and 

 analyzed, <rave their composition as 2 NaHZn- 

 Oi+rHaO, or 2Zn(OH)(OXa) + 7H 2 O. Hence 

 this new salt may be regarded as hydrated 

 sodium zincate. It is soluble in water and 

 alcohol holding soda in solution, but is decom- 

 posed both by pure water and alcohol. 



Some new salts of camphoric acid have been 

 described by J. H. Manning and G. W. Ed- 

 wards. Manning found that manganese cam- 

 phorate. MnCi Hi4O4. was precipitated from a 

 mixture of potassium camphorate and manga- 

 nese sulphate heated on the water-bath. It 

 is white. Chromium camphorate. Cr 2 (Cio- 

 Hi 4 04)3, was obtained as a bluish-green pre- 

 cipitate from a mixture of potassium camphor- 

 ate and solution of chromium sulphate. Fer- 

 ric camphorate. probably a subcamphorate, 

 resulted from the precipitation of a strong 

 solution of ferric chloride with potassium cam- 

 phoratc. It had a yellowish color and was 

 insolub'e in water, and gave on drying at 100 a 

 buff-yellow powder. A white heavy precipi- 

 tate of mercuric camphorate. Hg. C ; oH M O4, 

 was formed on adding potassium camphorate 

 to a concentrated solution of mercuric chloride. 



A new tetrahydric alcohol, CioH O 4 . be- 

 longinir to the series CnHsnO 4 , has been syn- 

 thetically prepared in the laboratory of M. 

 Friedel, by M. Combe-. It i> the tirst tetrahy- 

 dric alcohol which has been prepared by direct 

 synthesis, and is one of the results of the appli- 

 cation by M. Combes of the aluminum chloride 

 reaction of MM. Freidel and Crafts to the fatty 

 Series. 



A substance having all the appearance of silk 

 is prepared by M. de Chardoimet by the addi- 

 tion to an etherized solution of nitrated cellu- 

 lose of a solution of perchloride of tin, and to 

 this mixture a little of a solution of tannic 

 acid in alcohol. A tine stream of this liquid, 

 under water acidulated with nitric acid, be- 

 comes consistent, and may be drawn out, 

 dried, and wound. It is gray or black in as- 

 pect, supple, transparent, cylindrical, or flat- 

 tened, of silky aspect and touch, and breaks 

 under a weight of twenty-five kilogrammes the 

 square millimetre. The fiber burns without 

 the flame being propagated : is unattackable 

 by acids and alkalies of mean concentration, 

 by hot or cold water, alcohol, or ether, but is 

 dissolved in etherized alcohol and acetic ether. 



Saccharine is a coal-tar product which was 

 discovered in 1879 by Ira Remsen and C. 

 Fahlberg, and is distinguished by the intensity 

 of its sweetness, which is rated at two hun- 

 dred and fifty times that of cane-sugar. It is 

 prepared by a long and complicated process, 

 and has a composition which is represented by 

 the formula CjH 6 SO. It is a white powder, 

 or appears crystallized in short, thick prisms, 

 has an odor of bitter almonds, is hardly sol- 

 uble in cold water, more so in boiling water, 

 and quite soluble in alcohol and ether, and has 

 an acid reaction. When mixed in solutions or 

 used as a sweetening, it is hardly distinguish- 

 able to ordinary human tastes from sugar: but 

 it has been observed that insects are not at- 

 tracted to it, and some insects avoid it. It is 

 a strong antiseptic, and does not perceptibly 

 interfere with digestive action, except in an 

 acid medium, when its antiseptic power is 

 greatly weakened, and digestion is retarded. 

 It is not eliminated by the salivary or the 

 mammary glands, but is carried away in the 

 urine. It has been used to some extent as an 

 emollient in diabetes and intestinal affections, 

 and to prevent the absorption of the ptomaines 

 of the blood, but its value for these purposes 

 has not been settled. Xo use has been found 

 for it in ordinary economy, except to assist in 

 adulterations. 



On completing the filtration of a solution of 

 pig- iron in hydrochloric acid, P. W. Shinier 

 observed a minute residue in the beaker. It 

 was a gritty substance, with a steel-gray color 

 and metallic luster. Under the microscope it 

 appeared to be made up of opaque cubical crys- 

 tals and fragments of the same color and luster. 

 The material had a specific gravity of 5'10, 

 and was insoluble in hydrochloric, but readily 

 soluble in nitric acid. Upon analysis it was 



