84 



CHEMISTRY. (NEW PROCESSES.) 



with his classes for several years, as absolutely 

 safe and involving no loss of time. As soon as the 

 action begins collect the escaping gas in a test 

 tube, and when the tube is thought to be full of 

 pure gas remove 2 or 3 feet from the generator 

 JIIK! ignite the hydrogen in the test tube; then 

 immediately attempt to light the jet of hydrogen 

 with the hydrogen flame contained in the test 

 tube. If the gas is explosive it will explode in the 

 test tube and leave no flame. If, on the other 

 hand, a flame remains in the test tube with which 

 the jet can be ignited it is certain that the gas 

 in the generator is no longer explosive. Hence the 

 caution: Never light the hydrogen jet except with 

 the hydrogen flame obtained as just described. 



In the preparation of oxidomorphine, A. Loubiou 

 has obtained a very white and well-crystallized 

 product by the aid of peroxide of hydrogen. The 

 return by this new process is less than by that 

 with ferrocyanide, but the product is obtained 

 pure immediately; further, not more than an 

 hour is required for the performance of the opera- 

 tion. 



Two striking reactions of silver salts and solu- 

 tion of ammonium persulphate have been observed 

 and put under investigation by Dr. Hugh Mar- 

 shall. When a small quantity of silver salt is 

 added to a strong ammoniacal solution of ammo- 

 nium persulphate, nitrogen is evolved almost im- 

 mediately. The temperature rises rapidly, and the 

 action may soon become violent. Apparently the 

 silver is rapidly peroxidized by the persulphate 

 and reduced by the ammonia. In the second reac- 

 tion an aqueous solution of ammonium persulphate 

 was steadily decomposed at the ordinary tempera- 

 ture in presence of small quantities of silver salts. 

 No evolution of gas takes place, but part of the 

 nitrogen of the ammonium salt is converted into 

 nitric acid. It was found that in the space of two 

 or three days a milligramme-equivalent silver 

 salt per litre of solution decomposed one half of 

 the persulphate originally present, the temperature 

 being 20 C. 



The fact that the alkaloids cocaine, atropine, 

 and nicotine are derivatives of pyrol has suggested 

 experiments in synthesis of pyrol products. Among 

 the latest of these syntheses is that of pyrol alde- 

 hyde, the analogue of benzaldehyde and furfural- 

 dehyde, which has been accomplished by Bam- 

 berger and Djierdjian. The process was by Rei- 

 mer's reaction with chloroform and potash. The 

 new aldehyde forms a well-crystallized hydrazone, 

 oxime, and also an insoluble sodium sulphite com- 

 pound, but differs from its analogues in crystalliz- 

 ing readily and in having no smell. Prismatic crys- 

 tals of this substance several centimetres long have 

 been obtained. 



Among the different substances which have been 

 proposed for the biological purification of waters 

 oxidizing agents occupy a preponderating place, 

 especially the permanganates. The attempts at 

 purification by these means have, however, been 

 nullified by reason of the impurities introduced 

 by the reagent. For example, the use of perman- 

 ganate of potash and lime gives rise to the pres- 

 ence <f free alkali in the water, and small quan- 

 tities of free -lime (the alkali present in most 

 oases) make the water absolutely unfit for drink- 

 ing purposes. This difficulty may be done away 

 with by using permanganate of alumina and per- 

 manganate of baryta in variable proportions. The 

 reactions take place easily in the cold, and the 

 quality of the water can be determined five min- 

 utes after the addition of the first drop of the re- 

 agent. In some cases the- reaction is instanta- 

 neous. 



Having found that recently reduced nickel acts 



directly on acetylene, either slowly or with incan- 

 descence, Paul Sabatier and J. B. Senderens ex- 

 perimented with other substances. With platinum 

 black, iron, or cobalt the slow reaction was 

 scarcely perceptible, and the phenomenon was lim- 

 ited to the decomposition with incandescence, fol- 

 lowed by the more or less complete hydrogeuation 

 of a portion of the acetylene. Ethylene, on the 

 other hand, was rapidly decomposed above 300 

 C. by recently reduced nickel. The metal swelled 

 up considerably, and evolved a variable mixture 

 of methane, ethane, and hydrogen, accompanied 

 by a very slight proportion of higher formene 

 carbide. 



On reviewing the science of electro-chemistry 

 and its application to modern manufacturing pro- 

 cesses, " one is struck with amazement," says Mr. 

 F. Mollno Perkin in Nature, " at the enormous 

 strides which have been made within the last ten 

 or twenty years. On studying works on chemistry 

 little more than ten years old hardly a reference 

 is found to the use of electricity in metallurgy, 

 still less in regard to the manufacture of metallic 

 salts or of the nonmetals, and absolutely none in 

 reference to the preparation of organic chemical 

 bodies, at any rate, on a large scale." Within the 

 last few years electro-chemical analysis has been 

 very much studied, and now many laboratories 

 are fitted with special apparatus for pursuing it. 

 While the process for depositing metals from their 

 solutions has not undergone any radical change, 

 the means at our disposal for carrying out the 

 work have enormously improved. With the cheap- 

 ening of production since the advent of the dyna- 

 mo and the storage battery very much has been 

 made possible that would have been regarded as 

 visionary only a few years ago. Among the im- 

 portant applications for various purposes men- 

 tioned by the author is the preparation of copper 

 for electrical purposes, of which the absolute 

 purity required is hardly obtainable by furnace 

 methods. Such copper is, however, obtained by 

 the electric process, while the gold and silver pres- 

 ent in the metal are also separated and saved. 

 While zinc can not as yet be obtained from its 

 ores by electrolytic methods, zinc galvanizing by 

 electrolysis is used to a considerable extent in place 

 of the old method of hot dipping. The inner sur- 

 faces of tubes and the bottoms of ships, torpedo 

 boats, and other large surfaces are now galvanized 

 in this way, with a large saving of convenience. 

 Electrical processes are now used largely, too, in 

 the reduction of aluminum, the manufacture of 

 calcium carbide, gold, silver, and nickel plating, 

 the procuring of nearly all the metals from their 

 oxides, the purification of tin from gold, and the 

 making of accurately reflecting mirrors. 



Among the special processes to which electro- 

 lytic methods have been successfully applied, the 

 author mentions the preparation of a very pure 

 white lead from a dilute solution of sodium chlo- 

 rate and carbonate, the electrodes being of lead ; 

 of dye products, the nature ot which depends upon 

 the solutions employed, the strength of the cur- 

 rent, and the material of the electrode, by the 

 electric oxidation of aniline; the production of 

 hypochlorite bleaching solutions by the electroly- 

 sis of potassium chloride at low temperatures; 

 and the production of iodoform by the electrolysis 

 of a solution of potassium iodide and sodium car- 

 bonate with alcohol. 



In the simple method of Dr. R. Uhludruth for 

 preparing free hydroxylamine, when the phosphate 

 of the base is heated gently under reduced pressure 

 the base distills over in a state of such purity that 

 the distillate solidifies on placing the receiver in 

 melting ice. 



