OF CRYSTALS AND OTHER BAD CONDUCTORS. 
499 
II. Crystals. —Temperatures, mean of three experiments. 
Quartz Disc, 1 - 91 cm. diam., 1-005 cm. thick. Thermal stream lines parallel to 
optical axis. Air, 15°T C. 
Cool bar. 
Hot bar. 
v 1 10-09 A x 10-50 
Vn 4'64 Qj -1680 
k — (1-02) x 1 005 x 1 ’ 003 — -0298 
16-69 A 2 16-40 
v 2 26-28 Q 3 -1763 
k — (1-02) 1763 x 1005 x 1 003 — 0299 
1 ^ ' 16-40 - 10-5 x 1-010 
2 C ; 16-40 x 1-010 - 10-5 
h mean = '0299. 
Quartz Disc, 1 ’93 cm. diam., ’811 cm. thick. Thermal stream lines perpendicular 
to optical axis. 
Air, 16°'2 C. 
Cool bar. 
Hot bar. 
9-09 Aj 9-39 
v x 17-71 Ao 17-45 
* s 4-07 Qj -1545 
v 2 26-86 Qo -1616 
1545 x -811 x 1-004 
k _ 4616 x -811 x 1-004 _ .Q-^gq 
17-45 - 9-36 x 1-011 
2 17-45 x 1-011 - 9-36 
h mean = '0158. 
Iceland Spar Disc, 1*91 cm. diam., '70 cm. thick. Thermal stream lines parallel to 
optical axis. Air, ] 6°’4 C. 
Cool bar. 
Hot bar. 
t?j 7-82 A 1 8-10 
v 2 3 36 Q x "1436 
jc — Cl-02) 4436 x -7 x 1 004 _ .Q^nru 
v x 1873 A 3 18-49 
v 2 27-41 Q 3 -1478 
j. _ q.q 2) 4478 x 7 x 1"004 _ .q^qq 
1 1 } 18-49 - 8-10 x 1-013 
4 { 18-49 x 1-013 - 810 
k mean = '0100. 
Iceland Spar Disc, 1"93 cm. diam., ‘602 cm. thick. Thermal stream lines perpendicular 
to optical axis. Air, 16°’3 C. 
Cool bar. 
Hot bar. 
i\ 7'95 Aj 8'12 
Vo 3"33 Q x "1405 
_-1405 x -602 x 1-004 _ 
rj 18'61 Ao 18"37 
v 2 27 31 Q 2 -1475 
-1475 x -602 x 1-004 _ . nflfW 
1 18-37-8-12x1-012 
2 18-37 x 1-012 - 8-12 
k mean = '00845. 
3 S 2 
