( 616 ) 



to bring connection between the series V and VI. The results of 

 other series of observations are not communicated Iiere, because 

 for them all the precautions mentioned had not yet been taken. 



From the data of table II the course of the intensity of the 

 scattered ligiit with the temperature (§ 2 2'"^) will be derived in 

 the first place. Let us call HD,t the intensity in the spectrum of 

 the light scattered by the cloud at the temperature t of the wave- 

 length D for a certain arrangement of the apparatus, which is 

 further thought to be unmodified, Hncomp the intensity in the com- 

 parison spectrum when Nic^ is parallel with Nic^ and Nic^, then 

 ij)i =z Iïn,t/Ho,\ipm = sin^ <pn,tlsln* <^z>,ii.068- An investigation of the 

 absolute intensity of the light scattered by the mist compared with 

 that of the incident light (cf. § Qb) will have to reveal how to 

 derive a quantity from ij)^t which determines the intensity of the 

 scattered light, independent of the particular circumstances of the 

 arrangement. For an examination of the way in which the intensity 

 of the scattered light depends on the temperature, the quantity ij)^ t 

 is very suitable. 



Table III contains the results obtained on this from table II : 



TABLE III. 



These results have been represented in PI. II fig. 2, where also 

 a curve has been traced through the points of observation (see 

 further p. 620). 



The ratio rp .D,i=^ 



Hf, iJHf comp. sin*(pF,t 



— yields data for the in- 



HD,tlH£) comp. sin ' ^B,t 



quiry mentioned in § 2 1^^ into the ratio in which the light of 



different wavelengths is scattered. Table IV contains the results. 



