CHEMISTRY. 



riably accompanies cinnabar ; gold is associated 

 with it in a considerable number of cases; cop- 

 per sulphides or sulpho-salts not infrequently ; 

 and sulphides of arsenic and antimony and zinc- 

 blende sometimes. The waters of Steamboat 

 Springs are now depositing gold, probably in the 

 metallic state ; sulphides of arsenic, antimony, 

 and mercury; sulphides or sulpho-salts of sil- 

 ver, lead, copper, and zinc; iron oxide and 

 possibly iron sulphides; manganese, nickel, and 

 cobalt compounds, with a variety of earthy min- 

 erals. The sulphides most abundant in the de- 

 posits are found in solution in the water itself, 

 while the other metallic compounds occur in 

 deposits from springs now active or which 

 have been active within a few years. These 

 springs are thus adding to the ore-deposit of 

 the locality, which has been worked for quick- 

 silver in former years. There is reason to sup- 

 pose that deposition is also in progress at 

 Sulphur Springs. Experiments were .made to 

 determine the conditions of solubility and of 

 precipitation of quicksilver and the other me- 

 tallic constituents of the deposits in the various 

 earthy salts or mixtures of them, held in the 

 waters. They showed that there is a series of 

 compounds of mercury of the form HgSnXaS, 

 one or other of which is soluble in aqueous so- 

 lutions of caustic soda, sodic sulphhydrate, or 

 sodic sulphide, and apparently also in pure wa- 

 ter, at various temperatures. These solutions 

 :. to a greater or less extent, in the pres- 

 ence of sodic carbonates, berates, and chlorides. 

 There is strong evidence that the waters of 

 Steamboat Springs contain mercury in the same 

 form, if indeed they do not still carry it in so- 

 lution. Bisulphide of iron, gold, and zinc- 

 blende form double sulphides with sodium, 

 which appear to be analogous with that of 

 mercury. Copper gives a double sulphide, but 

 combines more readily with sodic sulphhydrate 

 than with the simple sulphide. All of the sol- 

 uble sulpho-salts may exist in the presence of 

 sodic carbonates. Mercuric sulphide is readily 

 precipitated from these solutions, by cooling, 

 by dilution, and by other conditions that inuy 

 be brought about among the substances exist- 

 ing in the solutions. 



In examining olive-oil for mixture of lard 

 oil, Mr. T. B. Warren confirms the presence of 

 poppy-oil by passing ozone into the mixture, 

 when a black product will be obtained by S.CI , 

 and the viscosity will be increased. The lard- 

 oil may be removed by boiling the coagnlum in 

 a moderately strong alkaline solution. The re- 

 maining mass is washed and treated for the esti- 

 mation of the iodine absorptions, when, knowing 

 the iodine absorption of the mixture and the 

 proportion of it due to the recovered lard-oil, 

 we have the difference corresponding to the 

 olive and poppy oils. If we know that two 

 oils only are present, and we know the iodine 

 absorption of each, we have no difficulty in fix- 

 ing on the quantities of each necessary to cor- 

 respond with the determination. 



The composition of the persulphide of hydro- 

 VOL. xxvni. 10 A 



gen has been determined by Dr. Rebs, of Jena, 

 to be II 3 S 6 . It is a bright-yellow, mobile, trans- 

 parent oil, possessing an odor peculiar to it- 

 self. When dry it may be preserved in a closed 

 tube without decomposition, but in contact 

 with water it breaks up rapidly, with evolution 

 of sulphureted hydrogen and separation of 

 sulphur. 



A new method of testing alcoholic liquors, 

 discovered by Prof. Schwartz, consists in deter- 

 mining the specific gravity and the index of 

 refraction of the substance under examination. 



Mr. Thomas Turner has experimented upon 

 the value of the sulphuric-acid method for esti- 

 mating silicon in iron and steel, and has com- 

 pared it with the aqua-ng'ia method. His 

 conclusions are, that with cast-irons of specially 

 good quality the silicon can be correctly esti- 

 mated by evaporation with dilute sulphuric acid; 

 with phosphoric irons the residue obtained, 

 though white, is often impure, and should be 

 further treated in order to obtain accurate 

 results; with phosphoric irons containing ti- 

 tanium, the silica is contaminated with iron, 

 with titanic oxide, and phosphoric acid. The 

 residue may be very nearly white and still 

 contain 20 per cent, of substances other than 

 silica; on treatment vrithaqua regia, the color 

 of the residue is usually an indication of its 

 purity. 



Chemical Synthesis. Dr. E. H. Keiser has 

 effected a synthesis of water, in which a known 

 weight of oxygen in the form of copper oxide 

 has been made to combine with an actually 

 weighed quantity of hydrogen. The weighing 

 of the hydrogen was accurately effected lo- 

 calising it to be occluded in palladium, where- 

 by a compound was formed which is stable at 

 ordinary temperatures, but gives out its hy- 

 drogen when heated. A new determination 

 of the atomic weight of oxygen by this process 

 gives it as slightly lower than 15 - 96 and more 

 nearly 15'87. 



Drs. Emil Fischer and Tafel have succeeded 

 in artificially preparing glucose directly from 

 glycerin. The glycerin was oxidized by means 

 of soda and bromine to aldehyde, and this 

 was subjected to a subsequent condensation by 

 means of alkalies. The synthesis had been 

 previously effected by decomposition of acro- 

 lein dibromide with baryta water, but the new 

 method is a far readier one. 



Bernthsen and Semper have produced by 

 artificial synthesis the substance nucine, or 

 juglon, which appears in the form of needle- 

 shaped crystals upon the outer coatings of 

 walnuts, and which has been found in the ex- 

 .1 juice of the same. 



The synthesis of crystalline dicalcium arse- 

 niate, or pharmacolite, has been effected by M. 

 Dufet through the slow interdiffusiou of so- 

 lutions of nitrate of lime and di-sodium arse- 

 niate. The gradual precipitation thus brought 

 about resulted in the formation of a group of 

 crystals exactly resembling those of pharma- 

 colite-monoclinic prisms of a pearly luster and 



