- lftf) Miscellaneous Intelligence 



■ beneath a burning candle, it is so combustible, that as it mixes with 

 the air it will burn with a voluminous flame, forming a striking ex- 

 periment. In small jars it will not burn, because it cannot mix 

 sufficiently with the air, or is dissipated, or preserved cool by the 

 vessel. — Silliman's Jour. vi. 



13. Amalgamation of Nickel and Cobalt by Arsenic. — It is 

 known that arsenic will amalgamate with mercury, but the influence 

 which it exerts in causing the amalgamation of other metals, which 

 when pure, shew no tendency to combine with mercury, is not 

 known. Wishing to amalgamate a portion of argentiferous grey 

 cobalt, mixed with kupfernickcl, seventeen ounces were pulverized 

 and mixed with mercury, added by degrees, in a mortar. After 

 adding eighteen ounces of mercury, an amalgam was obtained, which, 

 when washed and dried, weighed twenty-two ounces. The amalgam 

 had adhered to the mortar and pestle in considerable quantities. 



The mercury was separated from the amalgam by heat, ami 

 left ten and a half ounces of a metallic substance, of a fine silvery 

 white ; when roasted it gave out a strong odour of garlic, and consisted 

 principally of cobalt and nickel. 



A grey cobalt mixed with kupfernickcl from Allemont, and not 

 containing above 0.02 of silver, presented the same phenomena. — 

 Jour, de Phy., lxxxiv. \6~. 



14. Chromium in Ore of Platinum. — It has been shewn by a corre- 

 spondent in the Annals of Philosophy, vi. 108, that the ore of platina 

 contains chrome. It may easily be detected by separating the black 

 .sand, by means of a magnet, and fusing it with carbonate of potash in 

 a strong heat, when chromate of potash is found in the crucible. Its 

 nature was proved by dissolving the fused mass, neutralizing and pre- 

 cipitating with acetate of lead, a yellow precipitate fell down. This 

 collected and treated with muriatic acid, gave a white salt, and an 

 orange liquid which, after some boiling, became green. 



Vauquelin first remarked the existence of chrome in the ore of plati- 

 num, but Tennant threw a doubt on the subject, by stating his inability 

 to find it there. 



15. Test of Platinum. — Professor Silliman recommends the hy- 

 driodic acid, as the best test for platinum in solution. When dropped 

 into a weak solution, it almost immediately produces a deep wine red, 

 or reddish-brown colour, which by standing grows very intense. It re- 

 sembles the effect of muriate of tin, but is more sensible. On remain- 

 ing a day or two, films of platinum were deposited. The hydriodic 

 acid had been prepared, by putting phosphorus to about an equal 

 bulk of iodine, placed under water in a glass tube, so that it remained 

 mixed with acids of phosphorus, and perhaps phosphorus itself. No 

 other metallic solution gave similar results. — Silliman's Jour. vi. 376. 



