DE. A. E. H. TUTTON ON THE 
32 
Table of Molecular Refraction and Dispersion (Lorenz). 
Salt-. 
Molecular 
refraction, — - 
nr + 2 
M 
At = 
Molecular dispersion, 
m G - m c . 
For ray C (Ha). 
For 
ray Hy near G. 
P- 
7- 
a. 
P- 
7- 
a. 
P- 
7- 
RbMn sulphate 
59-70 60-13 
61-19 
60-98 
61-44 
62-59 
1-28 
1-31 
1-40 
AmMn 
59 • 99 60 • 42 
61-20 
61-46 
61 " 87 
62 ■ 66 
1-47 
1 -45 
1-46 
CsMn ,, 
65-29 65 - 4 S 
66-15 
66 ■ 67 
66 • 90 
67-60 
1-38 
1-42 
1-45 
Molecular Refraction (Gladstone and Dale). 
Salt. 
11 1 AI for ray C. 
a 
Mean molecular 
refraction for ray C. 
H a + P + 7)- 
cc. 
P- 
7- 
RbMn sulphate. 
AmMn ,. ..... 
CsMn „ . 
100- 72 
101- 29 
110-72 
101- 56 
102- 14 
111-12 
103 " 65 
103-67 
112-45 
101- 98 
102- 37 
111-43 
Optic A.rial Angle .—-The determinations with three pairs of excellent section-plates 
are given in the two following tables. 
Apparent Optic Axial Angle in Air, 2E, of AmMn Sulphate. 
Light. 
Plate 1. 
Plate 2. 
Plate 3. 
Mean 2E. 
Li. 
O ' 
115 46 
115 22 
o / 
114 57 
115 22 
C . 
115 58 
115 31 
115 6 
115 32 
Na. 
116 51 
116 8 
116 9 
116 23 
T1. 
117 18 
116 53 
116 50 
117 0 
Cd. 
117 43 
117 2 
116 59 
117 15 
F. 
118 5 
117 25 
117 10 
117 33 
