T’.. Scheerer on Polymerous Isomorphism. 39 
Il. Averric Tato anp Aveire. 
1. Silaugaee Talc. 
Si Fe Me H 
i : Gastein, 51-06 537 313 468 2846 '7-:28=99-98, Rr. 
z 4o74 672 320 G12 2732 «7°85, @u030=1005 
These i age give the ratios 26°51: 3-45: 12°42: 6-47, and 
25-83 :3 222 : 6-98, equivalent nearly to 8:1:4:2, The 
author his theory deduces the ratios 28°81: 14:58, and 
28°25 : 14:54, each very nearly 2: 1, or the augite ratio. 
2. Sparry Crystalline Talc. 
Si Al Mg Ga Fe Mn Hf 
a Tae Diallage, Presnitz, oe = 0-09 82:83 061 1:09 656=99°64 
0:06 32:07 0:81 1:01 039 656=9950 
Mean oxygen ratio, 30-40 : 0:04: 13-46: 5-83, becoming by 
Scherer s theory 30: 43 : 15 5°40, or nearly 2: 1. Some old analy- 
ses are reviewed and a like result deduced. 
3. Massive Talc. 
i 
’ 
; Si uM Be te te Re 
46. Neolite, Arendal, 5228 783 81°24 028 379 089 4-04=99'85 
a. * 4735 1097 2478 ... 792 264 628=99'19 
These give the oxygen ratios 27-15: 3-42: 13-62 : 3-59, ross 
24:58 : 4-80 : 12-24 : 5°58, equivalent approximately to 8: 1: 
or 10:2:5:2, Scheerer deduces by his method, the mie 
29-43 : 14-82 and 27-78: 14: 10, or nearly 2:1, the augite ratio. 
(It — observed that, throwing out the alumina and water 
€ remaining ratio is 27° 15: 13-62 for the first, and 24:58 : 12:24 
for the second, each very closely 2: 1.] 
Ca fo... Bi 
48. Neolite of Hisenach, 51°16 961 2965 191 082 650= 99°65 
8 : 5135 902 3019 193 0 
Ae f 5144 879 8111 200 Fe088 650=100-72 Rr, 
Oxygen ratios, 26-56 : 4-49 : 12°59: §°78, 2666: 421: 12°80: 578, 
and 2671 : 4-40 : 13-02 : 5°78, giving by the new theory 29° 
14:51, 29-47 : 14-73, 29-64: 14-94, each =2: 1. 
4. Nephrite. 
e 
1201 134 255—= 99-92 
25:91 1239 137 25610018 
53.“ WN Zealand, 5710 O72 2929 1848 339  250=10048 
Oxygen 
ratios, ¢ 29°85 :081 :14-07:2-27.—20°74: 0°82 : 1421 : 227.2965 : 0°84: 18-92: 2-29 
$ ratios, 30:06:1483 29°95: 14-96 29-87 : 14-66 
approaching in each ease 2: 1. 
Si lCUK COM 
Nephrite, Turkey, 5749 067-2586 
