mineral species independent of the Phenomena of Isomorphism. 409 
Analyses of the Crystals formed in the Alloys of Zine and 
Antimony. 
Stibiotrizincyle. Stibiobizincyle. 
cou Composition of the crystals oS ie allece Composition of the crystals 
synthesis, by analysis. by synthesis. by analysis. 
Per Per Per Per Per Per Per Per 
cent. cent. cent. cent. Sum. cent. cent. cent. cent. Sum. 
of Zn. | of Sb. | of Zn. | of Sb. of Zn. | of Sb. | of Zn. | of Sb. 
67:00 | 35°37 | 64:57} 99-94 
67-00 | 35°40 | 64:60 |7100-00 
67°50 | 34°62) 64:92] 99:54 
67:50 | 34:61) 65:39 /100-00 
68°50} 33:95 | 66:09 | 100-04 
70:50 | 33-62 | 66°38 |+100-00 
70°50 | 33°62) 66°38 |+100-00 
72°50 | 33°85 | 65°81) 99°66 
73°50 | 32:08 | 67°60| 99°68 
74:00 | 30:74, 69:06} 99°80 
74:50 | 30°43 | 69°51) 99-94 
75:00 | 29°88 | 70-20} 100-08 
75°50 | 28°76 | 71:24) 100-00 
76:50} 27:93 71:85| 99:78 
77:50 | 26°62| 73:27) 99°89 
78°50 | 24°83 | 74:74) 99°57 
79°88 | 20°58) 79°42} 100-00 
70°40 | 29:60 | 64:15 | 35°77 
66:50 | 33°50 | 61-00 | 39-00 
64°50 | 35°50) 53-50| 41-44 
Bee ce 55°49 | 44-42 
weweee | wwewee | weetee | aeeeee 
* Tn this analysis the antimony only was determined. 
+ In this analysis the zinc only was determined. 
The relation between the composition of the crystals Sb Zn? 
and that of the alloy in which they are formed, is discussed at 
length in the memoir already referred to. It is there shown to 
be a very simple function of the mass of metal which is in excess 
in the alloy, and of the force which determines the union of the 
elements in definite proportions. The whole order of these 
phznomena seem to the author to point to the existence of a 
power in the mass of metal which is in excess in the alloy, to 
disturb the action of the force, whatever it may be, which tends 
to unite the elements in definite proportions. There is, in the 
first place, a strong tendency in the elements to unite and form 
erystals having the exact typical composition; and secondly, 
this tendency is only overcome by a certain excess of either 
metal in the alloy. Then, again, the crystals of one compound 
obviously interfere with those of the other. This certainly has 
the appearance of one force interfering with the action of another, 
—the force of mass (if I may so call it) perturbing the action of 
the chemical force. But it is not my object at present to enter 
into a discussion on the cause of this variation. Moreover, since 
