182 
TRANSACTIONS OF THE 
Violle. 
pel GB 
seas 5% 
. .046. 
. -630 . 
mee OS 
OU 
826. 
Poh < SOM 
Millikan. 
~) aod 
TD 
. 092 
644 
te hak 
Bret) 
[APR. 1, 
The application of Cauchy’s formule to silver was made in 
the same way as in the case of platinum. For polished silver 
Quincke gives for the D. line, 
Prime angle of Incidence, 4 
Prime Azimuth, 
Formule (4) give, 
Formule (3) (2) and (1) then give 
a=. 
80 . 
UO awraciere 
nox 
Gaim tes 
COT: 
55 . 
Oe es 
ADT 
40 . 
Bo. 
30 . 
moles 
seOlad,. Se 
. .9606 . 
. .9482 . 
Opole 
. 9250 . 
bowls oe 
5g Ce BE 
cH BiH es 
. 8847 . 
saiter SH OT fag 
. .8695 . 
Ce ee 
5 sellei7t sie 
OQ ens 
.7510 . 
_ 7540 . 
£1632 . 
MMO: 
5 utiles 
| 7985 . 
8093... 
_ 8187 . 
. .8268 . 
A = 72° 10’, 
H = 41° 40’, 
( e = 82° 34.3’, 
( log. 6 = .4480 
ool Ks 1-K” 
U2 Gone: 1963 
~ ee 0304 = 2372 
pe 015 Moe 2489 . 
-720639:2 2460 
OOO; soee 2368 . 
. .0864 . 2260 . 
Se 9G: peiltciiae 
me lOGai2 bs .2015 
cee WES 1907 
Mig lao 1813. 
7 LOUD 1732 
nee Oe 
. .716 
. 655 
. .088 
Se Mey 
. 446 
 , B76 
"309 
. 246 
190 
- . 140 
It will be noticed that the agreement between these quantities 
p and those given by my experiments is closer than for either 
the platinum or the uranium glass; the largest difference being 
at 80°, where it amounts to .027. 
XV. 
EXPERIMENTS UPON GOLD AND IRON. 
Through the kindness again of Mr. Torrey and the Superin- 
tendent of the Sub-Treasury, I was permitted to make observa- 
tions upon a pot of molten gold; but accuracy of work was im- 
possible on account of (1) the rapidity with which I was obliged 
