r 166 ) 



The points E and F are agani deteimined by (10) and (10a). 

 For E we have (./; = 1, T= 0) ,x' = 0/1296 ; for'i^ (./' = 0, 7'= 0) 

 x' — 0,9535. 



Combining eqnation (6) for x^ and .r^', we find finally for the 

 eutectic point C: 



,r = 0,80673 ; ,r/ = 0,08893 ; ,/.'./ = 0,91107 ; T = 46(^,41. 



F'ormerjy, when x' could l)e neglected, we have found from (8), 

 ./ =0,809,"^ ^=452° (see IV). 



It is remarkable that the \'alue found for x./ is exactly equal to 

 1 — x/. It is eas3' to show that this is an immediate consequence of 

 the equations (6) (compare our pre\'ious paper). 



In cases however in which oui- assumption «/ = «./ (which fol- 

 lows from />/ =z fj_/) is not satisfied, the value of .c./ for the eutectic 

 point will also not be equal to 1 — ./'/. 



When the nmount of heat required f or the mixinfj of the jirst com])0- 

 nent for x = 1 is equal to that of the .second component for x = 0, 

 tlien the compositions of the tvo solid phases at the eutectic jioint loill 

 he complementary. 



YII. We shall now discuss the (jueslion, how the \\\u parts 

 ending in the cusps I' and li will gradually disappear. We may 

 follow this process step by ste[) in tiic fullowiug ligures. 



a) In tig. 10 we see that the ciisi) I* of the line 7' = f{.r), which 



. . d'^' / 



till now was situated msid(' thecurxe = 0, has n^^cA^^^/ that curve, 



in consequence of which the poiiil (^ of the line 7' = ƒ(./■') coincides 

 with P, and also with the maxiuniin point D, which lies between 

 /■* and Q. The curves T =: f {x) and 7'^f{.i'') run therefore both 

 horizontally in F, and henceforth the curve l' =z f {x') will no longer 

 touch the branch RP in PJ, but ihe branch PB (in a minimum). 

 After the horizontal position in fig. 10 the cusp at P will be turned 

 upvmrds instead of doAvmvards. 



This transformation is apparently determined by the relations 



x=:zx', —-, I.e. by 



T^ T,{l-ii\v"-)= rfl -\Ul--rA = rj^i3' .V{1-.^) . . . (13) 



This yields with the values assumed for T^ etc.: 



tJ' = 1,0611 ; ./• = 0,7006 ; T = 463\.5. 



b. The figures 11 and 12 show a second peculiarity of the tran- 



