

CHEMISTRY. (NEW PROCESSES ATOMIC WEIGHTS.) 



103 



The action of radiferous barium chlorid, con- many experiments were in progress with a view 



tained either in sealed tubes or gutta-percha to throwing further light upon the function of 



sheaths and held in the hand or carried in the the iron. 



pocket for from six to ten hours, has been found In the decomposition of the natural phosphates 

 by MM. Henri Becquerel and P. Curie to be at by sulfuric acid in the manufacture of super- 

 first to produce a slight redness of the skin near phosphatic fertilizers fluorin is released in the 

 the substance. This redness conforms to the form of hydrofluoric acid or of fluorid of sili- 

 shape of the tube and increases in intensity. The con, to the annoyance of manufacturers, and 

 skin next falls off from the part affected, and with danger of contaminating the atmosphere, 

 sinks in and begins to suppurate. Under proper For a time the gases were led through water, 



1 1 _ __.!__ P .1 t 1 f\ 1 .1 J 1 f 



treatment, which may last sometimes for a 

 month, the lesion heals and leaves a scar. In 

 one case a similar burn was experienced when 

 the substance was enclosed in a thin metallic 



and with the solution thus formed sodium, mag- 

 nesium, or aluminum fluosilicates were prepared, 

 which were of little use, except that the last two 

 might be applied to the hardening of stone. 



box. In general, the duration of the effect varies Fluosilicic acid has more recently been found to 



with the intensity of the active rays, and with 

 the intensity of the exciting action. 



New Processes. It has been found by Ca- 

 mille Martignon that tellurium, gold, and plati- 

 num in all their different forms are attacked 

 by a mixture of hydrochloric acid and oxygen at 

 temperatures much below that of the oxidation 

 of hydrochloric-acid gas in oxygen. The mix- 



have strong antiseptic properties, and to be very 

 useful as a preservative of manure, checking the 

 denitrifying action of bacteria, for which pur- 

 pose it surpasses plaster, kainite, and superphos- 

 phate of lime. In a recently patented preparation, 

 the fluosilicic acid is incorporated with clay in 

 a powder, which is accompanied by another pow- 

 der consisting of a porous substance saturated 



ture constitutes a chlorating agent for a great with sulfuric acid. When the powders are scat- 



number of materials. In the three cases men- 

 tioned its action can be compared to that of free 

 chlorin. 



With an apparatus essentially modified from 

 that of Hampson for the liquefaction of air, Mr. 

 M. W. Travers has obtained liquid hydrogen in 

 quantity. Hydrogen at a pressure of 200 atmos- 



tered over the manure pile, the antiseptic fluo- 

 silicic acid is generated by the action of the sul- 

 furic acid on the fluosilicates. 



Since the discovery of the compound of hydro- 

 gen and nitrogen known as hydrazoic acid nu- 

 merous modes of preparing it have been worked 

 out. Most of these depend upon the use of or- 



pheres is subjected to a preliminary cooling at ganic compounds. Purely inorganic syntheses 



80 C. in solid carbonic acid and alcohol. It 

 is then successively cooled by liquid air boiling 

 under atmospheric pressure and under a pressure 

 of 100 millimeters, after whicn it escapes from 



have been made by Wislicenus from sodium 

 amid and nitrous oxid, and by Tanater from 

 hydrazin and nitrogen chlorid. In a third syn- 

 thesis recently described by Tanater, a mixture 



the Hampson valve, and being sufficiently imper- of hydrazin sulfate and hydroxylamin hydro- 



feet gas at the low temperature ( 200 C.) ob- 

 tained by the liquid air boiling under low pres- 

 sure, regenerative cooling is produced, as in the 

 liquefaction of air by the Hampson machine. 

 Liquid hydrogen is thus obtained, and is col- 

 lected in a vacuum vessel which is specially iso- 

 lated from external heat. 



chlorid is treated in acid solution with an oxidiz- 

 ing agent and distilled, when hydrazoic acid 

 passes off with the distillate. 



Artificial silk is now manufactured in France 

 from wood-pulp dissolved in electrically made 

 bisulfide of carbon. The solution of wood-pulp, 

 prepared in the usual way, as for paper-making, 



The production of oxygen and hydrogen gases is squirted through glass nozzles of exceedingly 



by the electrolysis of solutions of caustic alkali 

 is carried on as a regular industry at works in 



small dimensions, whence it issues in fine hair- 

 like threads. These fibers are to all intents and 



Rome, Milan, Zurich, Lucerne, Hanau, Brussels, purposes silk as soon as the volatile solvent has 



and Paris. In the Schuckert electrolyzer a 15- 

 per-cent. solution of caustic soda is used as the 

 electrolyte, and the decomposition by the electric 

 current goes on so rapidly and regularly that a 

 continuous supply of distilled water is required 

 to keep the process going. The most efficient 



evaporated. They are then prepared in the usual 

 way and spun into threads. 



By a patented process lead dioxid is now pro- 

 duced electrochemically from a solution of an 

 alkaline chlorid in which litharge is suspended. 



Atomic Weights. In the annual table of 



work is given at a temperature of 70 ' C., with an atomic weights published by the International 



electro-motive force of 2.8 volts. With a Schuck- Committee, the values on the basis of O = 16 are 



ert electrolyzer 660 millimeters in length, 450 mil- given unaccompanied by the didactic table based 



limeters in breadth, and 280 millimeters high, a on H=l. The withdrawal of the didactic table 



primary charge of 50 liters of sodium-hydrate so- is explained to be in accord with a widely ex- 



lution, and a current of 600 amperes, 220 liters pressed wish. It is generally felt that if O is to 



of hydrogen, and 110 liters of oxygen at 15 be taken as =16 for any purpose, it should be 



C. temperature and 760 millimeters pressure are taken so for all purposes. In a paper read to 



produced per hour. the American Society of Science and Arts, Prof. 



The remarkable influence which is exerted by T. W. Richards appealed to chemists to conform 



traces of iron in determining and regulating the to the decision of the International Committee, 



oxidation of various organic substances was first He pointed out that O=16 has served as the 



observed by H. J. H. Fenton about twenty years experimental standard of reference in the great 



ago, and the observation has opened to him since majority of cases, that the great bulk of valu- 



a very wide and fruitful field of investigation, able work has already been published on that 



The work in it is still being extended in several basis, and that the use of this standard involves 



directions. In a communication by Mr. Fenton no great didactic difficulties; and he contends 



to the Cambridge Philosophical Society a brief that the decision of the International Committee 



summary was given of the researches on the is in itself an important reason for admitting 



ubject already published, and of new results this standard, and that uniformity of usage is 



vhich had recently been obtained. The condi- more important than any of the special adyan- 



tions of the oxidation method showed very close tages claimed by either side in the discussion. 



analogies with certain natural processes, and The only alterations of atomic weights in the 



