71 



after deducting a small portion of gas contained in it, is about 40 '2 ; 

 and of the amorphous kind, after deducting a much larger per-cent- 

 age of gas and of chloride of antimony, which it always contains, 

 the same; but the equivalents actually obtained, including those 

 substances, were 40*7 for the crystalline and 43*3 for the amorphous 

 variety. Amorphous antimony was found to be electro-positive to 

 the crystalline kind, both in acids and alkalies ; it was also thermo- 

 electro-positive to that substance ; and both reduced silver by im- 

 mersion in a solution of nitrate of silver. 



Both these substances when deposited are in unequal states of 

 cohesive tension at their two surfaces, frequently in so great a degree 

 as to rent the metal in all directions. But the most remarkable cir- 

 cumstance, and of which a brief account was published in the Philo- 

 sophical Magazine, January 1855, is, that amorphous antimony is 

 liable, by percussion or heat, to undergo a rapid and intense mole- 

 cular change throughout its mass, consisting apparently of a violent 

 commotion amongst its particles, similar, but in a much higher de- 

 gree, to the changes already observed by other experimentalists in 

 sulphur, selenium, iodide of mercury, &c., and attended by evolution 

 of an extraordinary amount of heat, sufficient, when the substance is 

 massive, to raise its temperature from 60 to upwards of 450 Fahr., 

 melting in several instances bars of tin and other metals. 



During the action the chloride of antimony and a portion of the 

 gas are expelled by the heat, and the substance loses its remarkable 

 property. After the action the antimony is found to have undergone 

 no oxidation, but to have considerably altered in its physical charac- 

 ters ; it has lost its steel-bright colour and become comparatively 

 grey, and has acquired a dull grey granular fracture ; its specific 

 gravity has also increased, and it has evidently passed a considerable 

 stage towards the condition of the other variety. The grey metal 

 undergoes no such change. 



By careful trituration of thin pieces of the amorphous metal under 

 cold water, it has been obtained in the state of a fine powder pos- 

 sessing the same molecular property. The chloride of antimony 

 adheres to the metal with considerable force, and is only partly 

 removed by digesting the powder in dilute hydrochloric acid for a 

 week ; and the gas contained in both varieties is only expelled by 

 pressing them. 



