549 
under constant P and the pressure at constant 7’ in order to 
pass from a limit-curve into the corresponding region. 
We take the equilibrium F=L+ F,+ F,+... of n—1 com- 
ponents in m phases (or of 2 components in 2 + 1 phases). Herein 
fF, F,... represent solid substances of invariable composition and 
L a liquid. On addition of a new substance X this occurs then 
only in the liquid. 
When in this equilibrium Z at constant 7’ and under constant P 
there occurs the reaction: 
; ALE Alo IE PV a De S02 peo (19) 
then E(Àz)—2, 2, when viz. a represents the concentration of the 
new substance in the liqnid. 
When we put A, =1, then 2(AH) and L(V) are the increases 
of entropy and volume, when one quantity of liquid is formed at 
the phase-reaction. We represent them by AH and AV. 
(12) and (15) pass now into: 
ze and (AP) =. REZ) 
When we represent by AW the quantity of heat which is to be 
added in order to form with the reaction one quantity of liquid, 
then (20) passes into: 
(dT)p = — 
redt as TRIE 8 
NT 
See l= Ry 
Reaction (19) may represent the common melting of the solid 
substances PF, F,...; this is the case when the reaction is of the form: 
VIRE IRE RR Le NEEN Eer (22) 
and when 4, 4, are positive. 
When the reaction is of the form: 
(d7)p = — 
(21) 
AT AR, Hated ag beta Po! ee ame . (23) 
in which we take also positive all coefficients, then it represents the 
conversion of the liquids 7, #,... into #,... when simultaneously 
liquid is formed. 
Now we assume that heat is to be added at the formation of 
liquid from solid substances, consequently at melting in accordance 
with (22) and at conversion in accordance with (23); then AW is 
positive; the change in volume at melting or conversion may be as 
well positive as negative. Now it follows from (21): 
The common melting- or conversion temperature of one or more 
substances is lowered by addition of a new substance; 
the common melting- or conversion-pressure of one or more sub- 
stances is; 
