428 Miscellaneoua hiteUigence. 



or green glass tube, and placed in the red lieat of a common fire, 

 until the cadmium has sublimed into the cool part of the tube; 

 then the residuum is to be shaken out, which is easily done with- 

 out loss of cadmium : a little wax introduced into the tube, and 

 a gentle heat applied, the metal melts, and by agitation forms a 

 button. 



Mr. Herapath thinks that the zinc smelter, if he were to put up 

 his tube earlier, and collect the first few pounds of metal separate, 

 would be able to collect abundance of cadmium, and aflbrd it at a 

 cheap rate for the purposes of the arts. — Annals of Phil. iii. 435. 



5. Cn/stallised golrl.—\\^\ien a solution of gold in ether is left for 

 a considerable length of time, the gold is gradually reduced, and 

 deposited in the metallic form, and crystallized. 



6. Stanniureffed Hi/drogen. — Professor Kastncr has observed, 

 that when tin is treated with moderately strong muriatic acid, 

 the hydrocren gas developed is combined with tin. It has a very 

 particular and penetrating odour : when compressed into water, a 

 considerable quantity is dissolved ; when burnt it produces a 

 blue light, and gives oft" white oxide of tin in fumes. When in- 

 troduced into a very weak solution of gold, purple of Cassius is 

 instantly formed ; and, applied in this way, the gas is a highly- 

 sensible re-agent for the minutest portion of the noble metal. Bis- 

 muth, when similarly treated, forms a similar substance. Both 

 these gases considerably resemble telluretted hydrogen. 



It may be observed, that, when treated in the same way, zinc 

 also produces a gas, containing large quantities of the metal when 

 recent. 



7. Deutoxide of Copper M. Berzelius says, "the deut oxide 



of copper attracts the humidity of the atmosphere very rapidly : it 

 is reduced so rapidly in hydrogen gas, that if a piece be highly 

 heated, but not red, and plunged into a bottle of the gas, the oxide 

 takes fire and is reduced, and water trickles down the phial. 

 According to the weight lost in this reduction, it appears to be 

 composed of 



Copper . . .79825 . . 100 



Oxygen . . .20175 . . • 25.272 



1.00000 



Ann. de Chim. xvii. 26. 



8. Preparation of Kerines Mineral. — M. Hensmans recom- 

 mends, thatinthe preparation ofthissubstance,thesulphuretofami- 

 mony, should be fused with caustic potash, and not with a carbonate : 

 for then, when a solution is made, and a current of carbonic acid 



