CHEMISTRY. (NEW PROCESSES.) 



83 



mica and be employed for insulators. It is also 

 certain that they can be advantageously used 

 as metallic lacquers. 



Essence of chrysanthemum is described by O. 

 Perrier as a greenish liquid of an oily consistence, 

 with a special odor recalling those of peppermint 

 and camomile. It begins to boil at 100 C. ; its 

 density is 0.932 at 15 C., and its index of refrac- 

 tion at 18 C. is 1.4931. It is soluble in 10 parts 

 of alcohol at 95 C., but is almost insoluble in 

 alcohol at 70 C. When cooled down to 15 C. 

 it deposits a small quantity of an amorphous 

 solid substance, which is probably paraffin. At 

 240 C. it becomes black; and it solidifies in a 

 mixture of ether and solid carbonic acid. 



A new gutta-percha lately discovered is the 

 product of a tree which grows principally at 

 Dunge, near Zanzibar. When the tree is tapped 

 a white fluid exudes, which, placed in boiling 

 water, coagulates into a substance strikingly re- 

 sembling gutta-percha. As the material cools 

 it becomes very hard, but while soft it can be 

 molded into any required shape. The experiments 

 made upon it indicate that while it may not 

 prove equal to gutta-percha, it will be suitable for 

 some of the purposes for which that material is 

 used. 



Among the products of the action of fluorine 

 upon sulphur recently investigated by M. Mois- 

 san, thionyl fluoride, SOF 2 , was noticed. MM. 

 Moissan and Lebau have made this fluoride the 

 subject of a more careful study, and have suc- 

 ceeded in obtaining it pure by the action of iron 

 upon thionyl chloride and by the interaction of 

 fluoride of arsenic with thionyl chloride. It is a 

 colorless gas, foaming slightly in moist air, and 

 possessing an unpleasant odor resembling that of 

 carbonyl chloride. It is easily condensed by the 

 action of carbonyl dioxide and acetone, giving a 

 liquid that boils at 32 C. In the absence of 

 moisture glass is not attacked by the gas at tem : 

 peratures lower than 400 C. Above this tem- 

 perature silicon tetra-fluoride and sulphur dioxide 

 are produced. Water decomposes thionyl fluo- 

 ride at ordinary temperatures, giving hydrofluoric 

 and sulphurous acids. Indications were observed 

 of another oxyfluoride of sulphur, not absorbed 

 by water and possessing a lower boiling point. 



New Processes. Of recent developments in 

 the textile industries, Dr. A. Liebmann mentioned 

 in the British Association the process for produ- 

 cing the peculiar " scroop " in silk and an increase 

 in luster on woolen fabrics by means of chlorina- 

 tion and bromination. He described different 

 modes of producing artificial silks from gun cot- 

 ton, cellulose, and gelatin, and referred to the 

 mechanical improvements made for increasing the 

 brilliancy of cotton fabrics and to the operation 

 for obtaining highly lustrous effects by mercuri- 

 zation. 



In a paper by Mr. A. E. Sunderland on appli- 

 cations of electro-chemistry in dye and print 

 works, the requirements to be fulfilled by a ma- 

 chine for electrical dyeing are defined as being: 

 1, the poles must not be of metal, but of carbon 

 or biscuit porcelain, which conduct by being 

 saturated with the electrolyte; 2. they must be as 

 near to one another as possible; 3, the cloth must 

 pass between the poles in the open width ; 4, the 

 poles may be perfectly smooth and perfectly cylin- 

 drical, revolving freely. These particulars are 

 necessary, because in the ordinary passage of the 

 electric current across any dye solution the tend- 

 ency of the dye is to concentrate itself around the 

 negative pole, and not to circulate freely in the 

 whole dye vessel. There is always thus a great 

 danger of unevenness. In the finishing of goods 



the peculiar effect called watermarking or moirr 

 can be produced by a process which resolves itself 

 practically into the local aplication of electroly- 

 sis. A platinum plate of suitable size is con- 

 nected with the positive pole of the source of cur- 

 rent. On this conducting surface is placed some 

 absorbent material saturated with a solution of 

 common salt. On this pad is placed the fabric 

 to be watermarked, and the plate engraved with 

 the watermark, connected with the negative ter- 

 minal, is pressed down upon it. The salt solution 

 is decomposed, and a facsimile of the watermark 

 is printed on the cloth. To produce opaque de- 

 signs the absorbent material is saturated with a 

 solution of barium chloride which is decomposed 

 on passing the current. 



Chlorine has been used by Traube and Bassenge 

 for the purification of water, Bassenge recom- 

 mending a dose of 0.0978 gramme of chlorine per 

 litre of water for ten minutes. Bromine, recom- 

 mended by Schimburg, gave the same result with 

 0.04 gramme per litre after five minutes' contact. 

 According to Allain,a dose of -nnsW) part of iodine- 

 kills all the nonsporadic pathogenic germs in half 

 an hour, as well as most of the saprophytes. F. 

 Mainejac has carried out a systematic series of 

 experiments with a badly contaminated water, 

 using varying equal quantities of chlorine, bro- 

 mine, and iodine per litre. Taking the lowest 

 quantity given by the above-mentioned authors 

 as the basis that is to say, 0.01 centigramme per 

 litre of water for half an hour he found that the 

 number of microbes per cubic centimetre was re- 

 duced from 17,500 in the original water to 300 by 

 the action of chlorine, to 190 by that of bromine, 

 and to 90 by that of iodine. 



From a number of papers, published in abstract 

 in the Moniteur Scientific ue, on the purification 

 of acetylene it appears that solutions of metallic 

 salts do not wholly remove the impurities, while 

 chromic acid and chloride of lime seem to be the 

 only substances that effect a complete purifica- 

 tion. Of these chromic acid is preferable, since ex- 

 plosions have occurred with chloride of lime. The 

 acetylene works which supply the Hungarian 

 state railways with gas use, according to M. 

 Pfeiffe, a solution of chloride of lime and plumbate 

 of soda, chloride of lime having been found likely 

 to cause an explosion. Experiments with the new- 

 mixture indicate that it is not dangerous. 



Up to the present time lithium has been ob- 

 tained by electrolyzing lithium chloride in the 

 molten state. The reason why this metal can not 

 be obtained from aqueous solutions by electroly- 

 sis is that it reacts with water, forming hydro- 

 gen and lithium hydroxide. If a solvent for a 

 lithium salt could be found upon which lithium 

 does not act, the metal could be deposited from 

 the solution by electrolysis, provided the solution 

 proved to be an electrolyte. Pyridine has been 

 found by Louis Kahlenberg to be a solution of 

 this kind. It will dissolve lithium chloride and 

 thus form a solution that conducts electricity. 

 The author has obtained lithium in white metallic 

 form from solutions of lithium chloride in pyri- 

 dine by electrolysis at room temperatures. It .can 

 be obtained thus from a comparatively cheap ore 

 in quantities sufficient for most scientific pur- 

 poses. Lithium, being an alkali metal that is not 

 very plentiful in Nature, has thus far not found 

 use in practical life in the metallic form: and the 

 indications at present are not that it will be used 

 in practice. 



In all the usual methods the ignition of a jet 

 of recently generated hydrogen gas is attended by 

 danger of explosion. The following method is rec- 

 ommended by C. G. Hopkins, who has used it 



