Foliation and Sedimentation — Lawson. 175 
which I have quoted above. For, the great belts of schistose 
rocks, like that of the Lake of the Woods, are just as truly 
foreign fragments in the gneiss, only on a grand scale, as are 
the smaller inclusions along the shattered confines of those 
belts. The limits of these schist belts are, as I have stated, 
usually schist planes and because of “the tendency of the folia¬ 
tion to assume relations to external material conditions'’ 1 due to 
differential pressure and consequent flow against these limiting 
schist planes, it cannot be urged as Prof. W. urges that “no 
reason can be given for supposing subsequent foliation would 
so closely follow the schistic sedimentation etc.” 
By the way, Prof. W. is strangely silent as to how these 
“foreign fragments” became imersed in the gneiss.” 
10. Prof. W. says : “ Injected veins do not prove the igneous 
origin of the whole gneissic mass.” Taken in connection 
with the inclusion of • the innumerable more or less angular 
fragments of the overlaying schist in the gneiss, near the con¬ 
tact, and often at considerable distances from it, and also in 
connection with the excessive metamorphism of the schists at 
the contact, such ‘veins’ certainly do prove the igneous origin 
of the whole igneous mass. “Nor” he continues, “do they prove 
a completely igneous condition of any part of it—but only a 
softened state, which, as we know, might be produced at a tem¬ 
perature far below that of igneous fluidity.” 
We know nothing of the kind. We have yet to learn that 
rock forming crystals, or an aggregate of such crystals, may be 
softened by any temperature so that they will flow without 
losing their crystallinity. Rocks or rock forming crystals may 
be crushed to any grade of fineness and made to flow in a solid 
condition by intense shearing or friction of the constituent 
parts one upon another, and so become very schistose, and have 
new minerals developed from the decomposition of the original 
constituents; but it is a fallacious notion that rocks may be 
softened in any other sense, so as to flow and still retain the 
individuality of their constituent crystals. When that indi¬ 
viduality is lost at high temperatures, whether the result be a 
state of “igneous fluidity” or a thickly viscid, or even colloidal 
state by reason of the pressure, the only term we have for the 
change is fusion, or hydro-thermal fusion; and we have a mag¬ 
ma, which, on recrystallizing, gives rise to a new rock devoid of 
