schaller.] MINER A LOG IC AL NOTES. 141 
The angles measured and calculated for the eight forms given are: 
Symbol. 
Measured. 
Calculated. 
No. 
Letter. 
Miller. 
4>- 
p- 
</>• 
p- 

/ 

/ 

/ 
o 
/ 
1 
b 
010 

01 
90 
00 

00 
90 
00 
2 
m 
110 
46 
11 
90 
00 
46 
10 
90 
00 
3 
h 
540 
52 
26 
90 
00 
52 
28 
90 
00 
4 
8 
310 
71 
46 
90 
00 
72 
15 
90 
00 
5 
I 
410 
77 
02 
90 
00 
76 
30 
90 
00 
6 
e 
011 

00 
35 
03 

00 
35 
04 
7 
d 
101 
89 
56 
36 
11 
90 
00 
36 
10 
8 
s 
111 
46 
11 
45 
22 
46 
10 
45 
23 
Besides these the prism t = {210} seems to be present on one crys- 
tal, though the reflection was very poor and the measured angle 
varies several degrees from the calculated 
value. 
Measured (0), 61° 55', calculated (^), 
64 21'. 
The new prism h = {540} occurs but 
onee. giving a fair reflection. 
The new prism £ = {410} occurs Ave 
times, once as a broad face and the other 
times as a narrow face. 
Goldschmidt does not give the form 
|<fc{l0l}in his Winkeltabellen, but Melc- 
zer gives the form as present on his 
crystals, and it also occurs as long, narrow faces on the crystals meas- 
ured by the writer. 
In habit the crystals differ somewhat from that shown in Dana's sys- 
tem, inasmuch as on the Nevada crystals the pyramid s is large, equal 
n size to the brachydome, thus making the prism faces subordinate in 
ize. The general appearance of these crystals is shown in tig. 12. 
(i Calculated angles taken from Winkeltabellen. 
