672 Scientific Proceedings, Royal Dublin Society. 
Or, as another example, suppose the two assemblages to be 
subjected to a uniformly applied force of attraction which affects 
them differently, so that when the patches of one of them exceed a 
certain size they have a relative motion with respect to those of the 
other, which causes them to pass to and assemble themselves at one 
end of the mixture, leaving only the patches of less magnitude 
mingled with the other assemblage at the opposite end. 
A large class of cases of solution, or diffusion of one liquid in 
another in variable proportions, may be cited as resembling the 
sort of intermixture here treated of. For comparison with the 
ease last alluded to, an instance of a pair of liquids commonly 
spoken of as not intermixing, may be referred to, e.g., water and 
ether. The two liquidsin these cases form two saturated solutions. 
which are moreover in equilibrium together. Thus in the case 
referred to, we have—l. A saturated aqueous solution of ether ; 2. 
A saturated etheral solution of water, and both solutions have the 
same vapour pressure.* 
Other kinds of diffusion are referred to later.’ 
Let us pass on to the consideration of the fourth class of effects 
mentioned at the opening of this memoir. 
IV.—The interlacing of different kinds of groups or individuals con- 
verting a fortuitous assemblage into an assemblage which 
approximates to homogeneity, but does not reach it because 
the arrangements for closest-packing are not homogeneous 
ones. 
This effect of the law of closest-packing is, in all probability, 
precisely that already treated of in dealing with thin curved 
assemblages ;* it is likely that in all cases where the closest-packed 
arrangement is not a homogeneous one, it will be some such 
symmetrical departure from homogeneity as that already shown 
to be productive of curved assemblages. 
A mass of similar assemblages of the kind referred to, if 
the curved fragments be of smai/ extent, will be practicaily 
1 As to saturated mutual solvents see Duclaux, Ann. chim. phys. (5) 7,267, 1876. 
Alexejew Wied. Ann. 28, p. 305, 1886. Comp. ‘‘Die Phasenregel” von Dr. W. Meyer- 
hoffer, p. 40 and Lothar Meyer, ‘‘ Grundztige &ec.,”’ p. 119. 
2 See page 679. 3 See p. 569. 
