122 Brush and Dana—Fuirfield County Minerals. 
Reddingite. Scorodite. Strengite. 
ss (vom Rath.) (Nies.) 
M1 4111 =~ 76° 50’ yr <8" 8" 20" 
Ninxiit = e516" 65° 20’ 64° 24” 
1I1L,]11 = 110° 43’ Lil" 111° 307 
The axial ratios of the three species are as follow :— 
c (vert.) b a 
Redd 1°0930 1°1524 : 
Seorodie > trea Rath) 1°1020 1/1530 i 
Strengite (Nies) 1°1224 1°1855 1 
The perre of the three species in chemical composition 
are spoken of in a later paragraph. 
emical composition.—T he best available material was used 
in the analyses by Mr. Horace L. Wells; it was free from 
every impurity with the exception of the quartz, which was so 
intimately intermixed that separation was impossible. The 
presence of the x bad however, did not interfere in the least 
with the accuracy of the composition finally deduced. The 
acne was determined directly. 
wo analyses gave 
I. {. Mean 
Quarts 12-09 12-07 12-08 
PO, 30°17 30°56 20°37 
MnO 40°85 40°58 40°71 
FeO 4°88 4°70 4°79 
Na,O (trace Li,O) 32 0:23 0-27 
CaO : 0-64 0°68 
H,0 11-76 11-33 1151 
100-71 100-11 100-41 
Excluding quartz, the mean of the two above analyses gives: 
P,0; 34°52 3 243 . 
MnO 46°29 652 
5-43 “075 . 
Na,O (tr. Li,O) 0°31 ca 146 ik 
014 
H,O 13-08 121 ‘121 3:00 
The ratio P,O, : RO: H,O=1: 8: 8, corresponds to the form- 
ula Mn,P,O . +8aq, which ono the following percentage 
composition :— 
PO, =< 34°12 
MnO = 52-08 
B,0. =. 18% 
It is interesting to note here that the same formula was 
deduced by M. Debray* for an artificial salt which he obtained 
in brilliant crystalline grains by boiling a solution of phos- 
* Annales de Chimie et de Physique, III, Lxi, 433, 1861. 
