444 RECURt) OF SCIENCE FOR 188? AND 1888. 



By Blomstraud a remarkable series of platinum bases contaiuiug 

 organic radicles and sulphur are described. In one memoir he dis- 

 cusses the sulphin bases of methyl aud ethyl, and iu a second paper, 

 jointly with Rudelius and Londahl, the propyl, isopropyl, butyl, iso- 

 butyl, aud benzyl bases are considered. The platoethylsuli)hin chloride, 

 Pt=(S(C2H5)2Cl)2, may be cited as a representative of these new com- 

 pounds. (Journ. Prakt. Chera. (2), XXXVIII, 315 aud 497.) 



Influence of imxmritieH upon gold. — Roberts- Austen, of the British mint, 

 investigating the influence of small impurities upon gold, attempts to 

 correlate his observations with the periodic law. Those metals whose 

 atomic volumes exceed that of gold, when alloyed with the latter ele- 

 ment, diminish its tenacity. Silver, having nearly the same atomic 

 volume as gold, hardly affects its toughness at all. So far as the ex- 

 periments go, the toughness of gold is not lessened by any element 

 which stands below it in Mejer's curve, while all the elements above 

 gold in the curve tend to umke it brittle.* (Berichte, xxi, ref. 508.) 



Salts of gold — In the periodic system gold may be placed with almost 

 equal propriety either in line with the alkaline metals or in column 

 with the iron and platinum groups. Chemically, its relations suggest 

 the first-named grouping ; physically, it is nearer platinum. In a for- 

 mer i)aper Krliss has shown that aurous oxide, like the alkalies, is com- 

 plerely soluble in water, and now Hottmann and Kriissfind alike state- 

 ment to hold good of aurous sulphide, which, when freshly prepared, 

 dissolves easily to a clear brown solution, from which it is precipitated 

 by hydrochloric acid and various salts. The trisulphide, Au^Sii ai)pears 

 not to exist, in spite of the common belief in its favor, but a suli)hide, 

 AU2S2, is easily obtainable. The so-called trisulphide of chemical liter- 

 ature is a mixture of this auroauric salt with free sulphur. (Berichte, 

 XX, 2309 ami 2704.) 



In experiments upon the halogen compounds of gold Kriiss aud 

 Schmidt conclude that Thomson's auroauric salts, Au^CU and Au2Br4, 

 do not exist. When chlorine or bromine acts directly upou gold the 

 normal auric compound is produced. (Berichte, xx, 263-1:.) 



ORGANIC. 



Eigher paraffins from hroivn coal. — In the oil distilled from brown coal 

 Kraflt has identified a number of the higher homologues of methane. 

 Ee has isolated the members of the series from CnHag to O23H48 inclu- 

 sive, and finds them to be identical with the normal [)arafiins prepared 

 synthetically. Seven of them are described in detail. (Berichte, xxi, 

 2256.) In other papers Kraftt studies aromatic compounds involving 

 pentadecyl and hexadecyl groups, such as hexadecyl beuzene, etc. {Ihid., 

 pp. 2265,3180.) 



The origin of petroleum. — Although petroleumisgenerally believed to 

 be of organic origin, some writers, and notably Mendelejefif, have sought 

 to show its derivation from inorganic material. Evidence as to its ani- 



