482 Scientific Intelligence. 



not the iso-acid. On attempting to repeat this process subse- 

 quently with carefully purified materials, no trace of the poly- 

 meric body could be found. The result was, however, readily 

 effected, after a few drops of sulphuric or hydrochloric acid were 

 added to the liquid before digestion. The ether is obtained in 

 beautiful crystals which may be heated to 180° with water with- 

 out change; though in presence of concentrated hydrogen chloride 

 it splits at 100° into methyl mercaptan and cyanuric acid. Similar 

 ethyl and amyl compounds were obtained. To obtain the sulpho- 

 cyanuric acid, the methyl ether was mixed with sodium sulphide 

 and heated in closed tubes to a temperature of 250° for three or 

 four hours. The solution, after filtration, was treated with hydro- 

 gen chloride in excess, whereby the sulphocyanuric acid was' pre- 

 cipitated as a yellow granular powder. It may be obtained 

 pure by conversion into the sodium salt and reprecipitation. It 

 is scarcely soluble in water, even boiling, and is also insoluble in 

 alcohol, ether, benzene and nitrobenzene. It has the formula 

 (NHIC — SH) 3 . The sodium, barium, silver, lead, copper, potas- 

 sium, lithium, calcium, magnesium and other salts are described 

 insoluble. — Ber.Berl. Ohem. Ges., xviii, 2196, Sept., ] 885. g. f. b. 



3. On the Synthesis of Cocaine. — Some months ago Merck 

 announced the production of a derivative of cocaine, benzoyl- 

 ecgonine. He has now succeeded in re-introducing the methyl 

 group into this derivative and in reproducing cocaine. For this 

 purpose the benzoyl-ecgonine was heated with the theoretical quan- 

 tity of methyl iodide and potassium hydrate in methyl alcohol, 

 in sealed tubes to 100°. The product obtained was identical 

 with the natural cocaine in all its physical and chemical proper- 

 ties. — Ber. Bert. Chem. Ges., xviii, 2264, Sept., 1885. g. e. b. 



4. On Hydrogen Persulphide. — Saba/tier has examined with 

 care the substance known as hydrogen persulphide with a view to 

 fixing definitely its composition. As ordinarily obtained it is a red- 

 dish-yellow oily liquid, varying in composition from H 2 S 6 to H 2 S I0 . 

 This uncertainty of composition is due to the free sulphur dis- 

 solved in the persulphide, the liquid saturated at 18° having the 

 composition H 2 S 10 . It contains also H 2 S dissolved, from which it 

 may easily be freed by placing it in vacuo. The persulphide was 

 prepared by Thenard's method by allowing a fine stream of cal- 

 cium polysulphide to flow into concentrated hydrogen chloride, 

 both cooled to 10°. The yellowish liquid, well dried, was then 

 distilled in vacuo, and afforded a clear brilliant, very limpid, mo- 

 bile yellow liquid, having an extremely irritating odor. While 

 retained in the bulbs which acted as the receivers, it was perma- 

 nent ; but it decomposed on decantation. On analysis, three 

 samples gave as the sulphur in excess of H 2 S 57*9, 59"2 and 58*9 

 per cent ; or 5S*7 as a mean. This corresponds nearly to the 

 formula H 4 S 6 , which requires 58*5 per cent. From these results 

 the author .concludes that the true formula of hydrogen persul- 

 phide is H 2 S 2 analogous to H 2 2 ; the excess of sulphur being due 

 to a partial decomposition in the process of distillation, the sul-' 



