250 Prof. 8". Airhenius on the Influence of Carbonic Acid 



(the earth). The values of A reduced in this manner are 

 tabulated below under the heading N. 



Angle... 40°. 39-45. 3930. 3915. 39 0. 3845. 38-30. 38'15. 38"0. 3745. 37-30. 



M 3-4 11-6 24-8 459 84-0 121 '7 161 189 210 210 188 



N 31 101 11-3 137 18-0 181 112 196 44-4 59 70 



Angle... 37°-15. 37-0. 3645. 36-30. 36-15. 360. 3545. 3530. 35-15. 35'0. Sum. P.c. 



M 147 105 103 99 60 51 65 62 43 39 2023 100 



N 75-5 62-9 56-4 514 391 379 392 376 36-0 28-7 743-2 372 



For angles less than 37° one finds, in the manner above 

 described, numbers that are a little inferior to the tabulated 

 ones, which are found by means of the absorption-coefficients 

 of Table II. and the values of N. In this way the sum of the 

 M's is a little greater (6*8 per cent.) than it would be accord- 

 ing to the calculation given above. This non-agreement 

 results probably from the circumstance that the spectrum in 

 the observations was not quite pure. 



The value 37*2 may possibly be affected with a relatively 

 great error in consequence of the uncertainty of the M-values. 

 In the following calculations it is not so much the value 37*2 

 that plays the important part, but rather the diminution of 

 the value caused by increasing the quantities K and W. For 

 comparison, it may be mentioned that Langley has estimated 

 the quantity of heat from the moon that passed through the 

 atmosphere (of mean composition) in his researches to be 38 

 per cent.* As the mean atmosphere in Langley's observa- 

 tions corresponded with higher values of K and W than K = l 

 and W = 0'3, it will be seen that he attributed to the atmo- 

 sphere a greater transparence for opaque rays than I have 

 done. In accordance with Langley's estimation, we should 

 expect for K = l and W = 0*3 a value of about 44 instead of 

 37*2. How great an influence this difference may exert will 

 be investigated in what follows. 



The absorption-coefficients quoted in Table II. are valid for 

 an interval of K between about 1/1 and 2*25, and for W between 

 0*3 and 2*22. In this interval one may, with the help of those 

 coefficients and the values of N given above, calculate the value 

 of N for another value of K and W, and so in this way obtain 

 by means of summation the total heat that passes through an 

 atmosphere of given condition. For further calculations I 

 have also computed values of N for atmospheres that contain 

 greater quantities of carbonic acid and aqueous vapour. These 

 values must be considered as extrapolated. In the following- 

 table (Table III.) I have given these values of N. The 

 numbers printed in italics are found directly in the manner 



* Langley, ' Temperature of the Moon/ p. 197. 



