342 ON TWO NEW CRYSTALLINE COMPOUNDS 



character of the combination is as described. The crystals do not have any distinct 

 cleavage, but it is possible that the basal plane O, which, as before stated, is seldom 

 seen, may be a cleavage plane. 



The composition of the crystals of SbZuj varies, as will hereafter be shown, with 

 the composition of the alloy in which they form. The crystals whose analyses are 

 given below were prepared by melting together 58 per cent of commercial antimony 

 and 42 per cent of zinc. The zinc was melted first, and when in fusion the antimony 

 was added. This involved a greater loss of antimony than if the opposite course had 

 been followed, as recommended above, which, with the impurity of the metal,* had the 

 effect of increasing the percentage of the zinc in the alloy about eight tenths of one per 

 cent. The crystals may therefore be regarded as having foimed in an alloy whose com- 

 position approximated closely to Sb. 57.2 per cent, Zn 42.8 per cent. The analyses 

 1, 2, and 3 were made by myself, of crystals from as many different crystallizations. 

 The fourth column gives the calculated composition of SbZuj on the supposition that 

 the equivalent of antimony =^ 129.032, and that of zinc = 32.527, as is generally 

 received. 



100.07 99.56 100.08 100.00 



From these analyses it appears that an alloy which contains 42.8 per cent of zinc 

 yields crystals of the same composition with itself, and corresponding to the calculated 

 composition of SbZug. 



The most characteristic property of the new compound is its strong affinity for oxy- 

 gen, w'hich gives it the power of decomposing water with rapidity at the boiling point. 

 This property led in fact to its discovery. The author, while washing with hot 

 water some granulated alloy, having the composition of SbZuj, which had been used 

 for preparing antimoniuretted hydrogen, observed that the metal continued to evolve 

 gas after the last trace of acid had been removed. The singular phenomenon was at 

 first referred to an increased activity of the zinc in the alloy, produced by the galvanic 

 action of the particles of antimony set free by the action of the acid. This theory was 



* The zinc used in these experiments was nearly pure. The antimony was a good article of commercial 

 antimony, containing about one per cent of impurity, which, with the exception of a slight trace of arsenic, 

 was not taken up by the crystals. 



