448 J. W. Gibbs—Hquilibrium of Heterogeneous Substances. 
ties which prevent the commencement of discontinuous changes. 
But a phase which is unstable with respect to continuous 
changes is evidently incapable of permanent existence on a 
large scale except in consequence of passive resistances to 
change. To obtain the conditions of stability with respect to 
continuous changes, we have only to limit the application of 
the variables in (14) to phases adjacent to the given phase. 
_ The equation of the limits of stability with respect to con- 
tinuous changes may be written 
2 
(7) = Oo (<2 =o, (15) 
dy t fy, ee oe fa—1 d,? t, Fay cee Se -n—1i 
where 7, denotes the density of the component specified or 
M,~v i 
suffix , is regarded as relating. 
Hn ey (++) 
BY alt yy. pany | yg? ]8 yy. . pants 
pecan 
