134 
CONTRIBUTIONS TO MINERALOGY. 
[BULL. 26 
Twenty-five forms are present on the twelve crystals measured 
They are: 
c =100 
,4 = 1.10.0 
b =180 
/ =140 
a =130 
e =120 
5=590 
a- 
=470 
h = 
=350 
C-- 
=580 
I) 
=570 
i = 
=340 
E-- 
=790 
5=450 
q=U 
k =560 
O =11 
r =670 
u =22 
d=110 
x =12 
K=1U 
ip=U 
m=113 
go=13 
The average of the angles measured with the calculated angles ar 
shown in the following- table: 
No. 
Letter. 
Symbol. 
Measured. 
Calculated. 
4>. 
p- 
4>- 
p- 
o 
/ 

/ 

/ 
o / 
1 
c 
100 
90 
00 
90 
00 
90 
00 
90 00 
2 
A 
1.10.0 
5 
49 
90 
00 
5 
43 
90 00 
3 
b 
180 
7 
08 
90 
00 
7 
08 
90 00 
4 
/ 
140 
14 
03 
90 
00 
14 
02 
90 00 
5 
a 
130 
19 
06 
90 
00 
18 
26 
90 00 
6 
e 
120 
26 
34 
90 
00 
26 
34 
90 00 
7 
B 
590 
28 
59 
90 
00 
29 
03 
90 00 
8 
a 
470 
29 
30 
90 
00 
29 
45 
90 00 
9 
h 
350 
31 
04 
90 
00 
30 
58 
90 00 
10 
C 
580 
31 
59 
90 
00 
32 
00 
90 00 
11 
I) 
570 
35 
17 
90 
00 
35 
32 
90 00 
12 
% 
340 
36 
52 
90 
00 
36 
52 
90 00 
13 
E 
790 
37 
47 
90 
00 
37 
52 
90 00 
14 
8 
450 
38 
39 
90 
00 
38 
39 
90 00 
15 
€ 
560 
39 
48 
90 
00 
39 
48 
90 00 
16 
r 
670 
40 
36 
90 
00 
40 
36 
90 00 
17 
a 
110 
45 
00 
90 
00 
-15 
00 
90 00 
18 
K 
114 
45 
00 
19 
25 
45 
00 
19 28 
19 
m 
131 
18 
33 
72 
45 
18 
26 
72 27 
20 
9 
r 112 
I 121 
26 
44 
34 
59 
65 
35 
54 
15 
26 
45 
34 
00 
65 54 
35 16 
21 

111 
45 
00 
54 
44 
45 
00 
54 44 
22 
u 
( 122 
1 221 
45 
26 
00 
34 
70 
48 
31 
13 
45 
26 
00 
34 
70 31 
48 11 
f 123 
26 
35 
36 
40 
26 
34 
36 42 
23 
X 
J 132 
18 
31 
57 
40 
18 
26 
57 41 
1 231 
33 
42 
74 
30 
33 
41 
74 30 
24 
If, 
124 
26 
20 
28 
40 
26 
34 
29 12 
25 
GO 
134 
18 
18 
39 
37 
18 
26 
38 19 
