Intelligence and Miscellaneous Articles. 231 



decomposes the salt and reduces the oxide, the metal of which floats 

 on the fluid in the form of a brilliant metallic pellicle. 



The solutions of palladium, whether in nitric or in muriatic acid, 

 or in aqua regia, require only a slight excess of acid to possess rather 

 a yellowish brown colour, than a reddish one, with a styptic and 

 metallic taste ; they mix with water in all proportions without be- 

 coming turbid; when neutral, or with only a slight excess of acid, 

 they are decomposed by water into sub- and super-salts. — Ibid. 



PREPARATION OF CONTA, THE ALKALI OF THE CONIUM MACU- 

 LATUM. BY M. BRANDES. 



The best method of obtaining this alkali is to digest the fresh 

 herb in alcohol during some days, afterwards evaporating the fil- 

 tered alcohol, agitating the residuum with water, and treating this 

 mixture either with alumina, magnesia, or oxide of lead ; the whole 

 is to be evaporated to dryness, and the residuum obtained treated 

 with a mixture of alcohol and aether, which, when again evaporated, 

 leaves the conia. This substance, which was discovered and also 

 named by M. Peschier, possesses very marked alkaline properties. 

 According to M. Giseke, the aqueous solution forms, with the tinc- 

 ture of iodine, an abundant reddish precipitate ; it renders tincture 

 of galls slightly brown, precipitates muriate of zinc and nitrate of 

 mercury of a dirty yellow ; renders carbonate of potash and soda 

 slightly turbid ; gives a brown colour to muriate of platina ; and pro- 

 duces a white precipitate with the nitrates of silver and barytes, the 

 acetates of barytes and lead, muriate of lime and lime-water, 



Haifa grain of conia is sufficient to kill a rabbit j the symptoms 

 which occur resemble those produced by strychnia. — Ibid. 



ON PYROPHORUS. 



M. Gay-Lussac, in forming this substance, used calcined lamp- 

 black instead of honey or flour, usually employed. Potash-alum 

 heated with this form of carbon, gave at first carbonic acid and sul- 

 phurous gas, and nearly in equal volumes ; afterwards carbonic acid 

 was obtained nearly pure, and at last it was mixed with oxide of 

 carbon, and this eventually prevailed. The pyrophorus so formed 

 burnt readily. M. Gay-Lussac is of opinion that carbon is not ne- 

 cessary to the combustion : he made a mixture of nearly 75 parts 

 of alum, and 3-33 of lamp-black, or 1 atom of the former and 3*5 

 atoms of the latter ; and this mixture, when calcined, at nearly a 

 white heat, gave a reddish-brown product, containing no traces of 

 carbon, but it burnt very readily, and left a grayish-white residuum. 

 Alum is not essential to the preparation. Sulphate of magnesia 

 produces the same effect ; sulphuret of potassium alone does not, 

 however, inflame spontaneously in mass ; and it occurred to M. 

 Gay-Lussac, that alumina or magnesia acted merely by dividing the 

 sulphuret ; that this was the case was proved by substituting char- 

 coal for them, and though the compound obtained, by using 27*3 of 

 sulphate of potash, or 1 atom and 7 5 of lamp-black, or 4 atoms 



agglutinated 



