190 
Parr- 
— The Response of Pilobohis to Light . 
Light 
source. 
Standard of 
comparison. 
Spectral 
region. 
Galvanometer deflex- 
ions in min. 
Corrected deflex¬ 
ion in mm. 
Tungsten 
lamp 
±589 
±589 
(Yellow) 
G al vanometer ch anged 
in sensitivity. 
y±5§9 used for com¬ 
parison. 
430-310 = 120 
450 " 330 =i 20 
495 “ 355 = I 4 ° 
520-380= 140 
Average = 130 
292 
)> 
±631 
(Orange) 
440-130 = 310 
430-135 = 295 
445 — 1 3 ° = 3*5 
435 ~ 1 3 ° = 3°5 
Average = 305 
688 
a 
±589 
(Yellow) 
Galvanometer changed 
in sensitivity. 
400—230 = 170 
405-240=165 
425 — 260 = 165 
435-260= 175 
Average =169 
378 
>> 
+ 667 
(Red) 
610-225 = 385 
610-215 = 395 
580-190=390 
590-195 = 395 
Average = 391 
879 
>> 
+ 612 
(Orange) 
438 — 232 = 206 
445 —238 = 207 
495-275 = 220 
Average = 211 
474 
tt 
±523 
(Green) 
310-225= 55 
395 - 3 1 5 = 80 
420-345= 75 
440-365 = _75 
Average = 71 
162 
±464 
(Indigo) 
315-278= 37 
328-290= 38 
410-372= 38 
385 ~ 34 ° = _ 45 _ 
Average = 39.5 
89 ■ 
y> 
±437 
(Indigo) 
210-185= 25 
210—185= 25 
250—228= 22 
250—220= 30 
Average = 25 
56 
tt 
± 398 
(Violet) 
440-432= 8 
488-478= 10 
508 — 498= 10 
508-499= 9 
Average = 9 
Galvanometer changed 
in sensitivity. 
20 
ii 
± 5 S 9 
(Y ellow) 
358-128 = 230 
365-140=225 
365 - 1 45 = 2 20 
Average = 225 
506 
Ergs per sec. 
per cm . 2 
2*480 
5'843 
2*480 
5.760 
3-109 
1*050 
0-578 
0*364 
0*130 
2*480 
