MR. G. A. SCHOTT ON THE REFLECTION AND REFRACTION OF LIGHT. 841 
These give at normal incidence 
R3 = 
+ /^o 
1 + 4SVo/^i 
(A — (A — Ii{-) + (B — C) (/i-d — ^^n) 
S2 = 
■ 1/^0 
1 - 
(A - (A - + (B - C) (/.d - 
4- 
Vibrations Parallel to Plane of Incidence {Electromaynetic and 
Theories). 
Contractile Ether 
The equations (VI',) p, 838, give on substitution for tq, since, in this case, r, .s' 
are zero, 
— cos \ (1 -j- r) — 8® ^ j + cos qs ^1 + 8^ —^ = 18 «/x^, (1 — r) 
— cos 4 (1 + r) (I + 8" —^ + cos qs fl — 8" — ] ~ l Bajx^s, 
or. 
cos t, 
— t 8a — 8^ — ) — cosq^Yl + 8^—] = — cos^y fl + t 8a — 8^ 
cos 'I'Q it 
cos I, 
0 
a 
a 
— COS irO '. (1 +8^ —^ + cos i.s f 1 — t 8a —-t — 8 ‘^ —^ = cos L f I -1- 8^ ~ 
^ \ a ! ^ \ cos a j \ a 
whence 
r 
A 
1 _ t 8a - 8" —) f 1 - t 8(6 - 8^ — ) - (l + 8’ 
cos Iq 
a 
cos i 
a 
- 1 + 6 8a ~ 82 
cos ^0 a 
/^U S2 M \ ^ _ 8'-^ —) + (l + 
cos I 
1 — 
/^u 
- 82 
iVl 
cos 4 
a 
2t 8a 
i. 
cos q 
8a 
cos I 
82— )- 
1 
I 4- S' — 
id 
1 + 82 
a 
or. 
5 i> 
MDCCCXCIV.—A. 
