— ate 
'€ 
se ati ae aS i SM Be a RRS ee eat ea 
ena 
Fale teh ee 5: = 
er oe 
“pe ee 
oe 6 eee Ss 
4 
Dg ae ae 
8. P. Langley—Atmospheric Absorption, ‘177. 
Ae BeOS oak .= J =1, though this condition is 
not necessary. It will be observed, however, that under it in 
the second column Aa = a, Bb = b, ete., so that the coefficients 
©o 
f sranataiasion, the ratios of each geometric progression, are 
the same in this particular column, as the intensity after 
absorption.) 
TABLE II. 
aE IL. +E; IV. ag 
Original intensity Observed intensity suansgrl t Ayia Observed intensity! Observed intensity 
(oeroeaa) Be one after aban after four 
unknown. “naa rettoe sorptio n 
A, B, G, ete. ae Bb, Ce, ete. |Aa?,Bb?, Cc’, etc.| Aa®, Bb, Cc’, ete.| Aa’, Bb4, Cc4, ete. 
1 ‘OL “0001 000 -0000 
1 ¢ ‘O1 001 “0001 
1 2 04 008 ‘0016 
1 6 36 216 1296 
] 4 49 343 2301 
1 iN 49 343 2301 
1 8 64 512 4096 
1 a) “81 729 "6561 
1 ‘9 ‘81 “129 *6561 
1 10 1:00 1:000 1:0000 
J0= poo 4°65= 3-881 = 3°3143= 
A+B+ete. Aa+Bb+ete. |Aa?+Bb?+etc. | Aa*+ Bb +eic. | Aat+ B-dt + etc. 
ee =M =N =0 =P 
If we determine the coefficients of transmission from a com- 
parison of IT and III, we have a= 7893 
7 O\5 
if from II and IV, we have (x) ='812; 
if from II and V, we have (5 ¥_.g05 
and the corresponding mean absorptions are 
N O\4 P\} 
laa = = (2)? =o —(— )* =0175. 
yO?) 1 (x) 07188, 1 (5) 0175 
So that all our observations at very different altitudes are in 
substantial agreement in indicating an absorption of from 18 to 
21 per cent, while yet all our inferences from them are quite 
ie 
f we observed by some method which discriminated between 
ve different radiations of which the heat or light is core 
we should have from the observations in columns IJ and IIL 
A Bé)* C . 5 ee 
Aemeon... 5 « GY 4 CO « sale 
‘01 “| : 
0 
“0001 Re 01 + at etc. ee =4¢ 
