( -253 ) 



d'T 



This expression for I ^1 is sdll \cy\ coinplicatcd, oven after the 



\dx- y„ 



great siin[)liticati()iis, which attend the intro(hicti(jii of ,/• =: ./;' = 0. 



fd-'T 

 Besides bv a direct calcidatioii, the corresponding valne lor — - 



\d.v. \ 



may also be fonnd by changing letters and signs as mentioned 



above, a]id the latter method is even the easier. Then we get: 



'hi 1-777 T^tM - \ h-iT~2iq.^-la-a') - 



dw" 



7i 



d.v' 



T. 



,v 

 a — a ' 

 <h V •*' 



7', 



x' 



In tlie discussion ot the two ({uantities and — 



(/,/■" /„ V dx 



(0. 



two 



limiting cases are chiefly Avorthy of consideration, xiz. a' = x and 

 a' =: 0. Let us further always put a (latent heat required for the 

 mixing of the liquid phase) :=: 0. 



X 



a. For a =z cc - becomes exponential Iv = 0, hence 



X 



Lim. I «' — j will be 0. The two expressions are then Irausfoi-med 

 into : 



d'T 



d^ 



d'T 



17' 





1 fdT\ 



i. e. iiito: 



dx' 



'h K^^'^'Jo L ^'i 

 1 /dT 





1\ III \ Mo 71' 

 ft I ^ 



7i 



'Ix 



(Vx-4^\) 



dx-J„ 'h l^.'Vo^^^'' Wo 



7'A. 



{r.'r= X) 



(10) 



These expressions teach us, that in case the solid phase contains 



nPT\ 

 very little or nothing of the second conn)onent, — — becomes 0, 



when Yj = 4 7',. In this case therefore the [)()int of iidlection npjtcars 

 in the curve T., /{.)•) exactly at .v = 0. 



