and Soft States in Metals. 263 
oriented units. In attenuated forms like leaves or thin films 
the structure is determined by surface-tension, and has none 
of the characteristics of crystalline aggregation *. 
25. The micro-structure of hardened silver is vitreous 
looking on the surface, ana finely granular immediately below 
the surface. The forms assumed by surfaces and edges are 
rounded and smooth, and suggest the flow of a viscous liquid. 
When the glassy surface is carefully removed by a solvent, 
the granular structure underneath is more fully disclosed. 
By further action of the solvent this granular layer may be 
completely removed, disclosing the crystalline grains or 
skeletons of the C phase more or less deformed or broken up. 
26. It seems probable that the granules which are thickly 
distributed through the vitreous layer are produced by the 
breaking down of the lamellee and the setting free of the units 
of which they are built up. The granules and their vitreous 
matrix always appear at surfaces of flow, the thickness of the 
layer being determined by the thoroughness of the flow at 
that particular place. The persistence of the units of the 
C phase in the granules may be accounted for by their being 
encased in an envelope of the hardened A phase. 
27. Within a mass of metal the flow never reaches the same 
degree of completeness as it does at or near the outer surfaces, 
the relative amount of the hardened phase which is produced 
may therefore be smaller ; butit wiil be found encasing units, 
lamellze, or grains at all surfaces at which slipping has occurred, 
cementing them together, and producing a conglomerate in 
Fie. 1, 
7) 
which the hardness is much greater than that of the annealed 
phase, but less than that of the completely transformed 
A phase. 
28. Figs. 1 and 2 are diagrammatic sketches in which I 
* Proc. Roy. Soc. vol. lxxil. p. 232. 
