AND TRANSMITTED BY CERTAIN KINDS OP GLASS. 
269 
Tables X. and XI. give the details of these experiments 
angle of incidence was 7° 30', and with the flint glass 10°, 
with the crown glass the 
Table X. 
Crown Glass. 
Per cent, of 
1 
Xi. 
(x - Xi.) 
a?2. 
(x — Xj.) 
incident light 
reflected. 
December 21, 1887.—Re- 
157-8 
93-1 
65-0 
185-9 
4-25 
polished with putty 
157-0 
93-9 
64-8 
186-1 
4-34 
Mean 
4-29 
January 5, 1888 . 
157-8 
93-1 
64-3 
186-6 
413 
150-6 
94-3 
63-9 
187-0 
4 23 
156-0 
94-9 
63-5 
187-4 
4-25 
Mean 
4-20 
January 7, 1888.—Repolished 
155Y 
95^2 
63-0 
187-9 
4-20 
with rouge 
154^9 
96-0 
62-6 
188-3 
4-24 
155-5 
95‘4 
63-3 
187-6 
4-28 
156^2 
94-7 
63-2 
187-7 
4-17 
Mean 
4-22 
June 13.. . 
159-6 
91-3 
67-5 
183-4 
4-43 
159‘6 
91-3 
67-3 
183-6 
4-40 
159-8 
91-1 
67-7 
183-2 
4-44 
Mean 
4-42 
June 14.—Repolished with 
160-8 
90-1 
68-1 
182-8 
4-36 
rouge 
1 
160-9 
90-0 
67-6 
183-3 
4-25 
160-9 
90-0 
67-8 
183-1 
4-29 
Mean 
4-30 
