MEANING OF ROCK FLOWAGE. Bil 
are in a state in which solution is easier than for unstrained or larger 
mineral particles. However, it is probable that the solution of such 
mineral particles and the deposition of the material in an unstrained 
crystallized condition is considerably slower than that of amorphous 
glass, for it cannot be supposed that the same amount of energy is po- 
tentialized in the mineral particles as in the glass. But the further the 
strain goes before fracture the more energy is potentialized, or if frac- 
tures occur smaller particles are produced. Moreover, the contained 
water is in small capillary or subcapillary spaces, and therefore a given 
volume is acting upon a. much larger surface than in the capillary 
tubes used by Barus in hisexperiments. Inso faras granulation occurs, 
the surface of action is still further increased. All these conditions are 
favorable to solution and redeposition ; therefore the greater the strain- 
ing and resultant granulation, the more rapid the process of recrystalli- 
zation ; hence in the deep-seated zone mechanical disintegration never 
gets far in advance of solution and redeposition (see pages 303-305). 
If it be supposed in the capillary and subecapillary spaces within the 
rocks that the speed of solution of minerals is .1 of that of glass, water 
would dissolve its own volume of minerals and redeposit the material in 
about five hours. If the deep-seated rocks be supposed to contain 2 per 
cent of water by volume—that is, less than 1 per cent by weight—the en- 
tire mass of rocks might be recrystallized in about 250 hours, or little 
more than 10 days. The percentage of water premised is known to be 
lower than the amount ordinarily found in the crystalline schists (see 
page 308), and the rate hypothesized seems reasonable; but if this speed 
be decreased to .1 of that suggested or to .01 of that of glass, still the 
entire mass of the rocks might be dissolved and redeposited in about 100 
days. Make the rate .1 of this or .001 of that of glass, and still recrys- 
tallization might be complete in about 1,000 days, or three years. If it 
be supposed that a mountain-making period occupied 150,000 years, and 
this is probably less. rather than more than the time required for most 
mountain-making movements, during this period, at the slow rate sug- 
gested, the rocks could be recrystallized 50,000 times by 1 per cent of 
water, and this number certainly seems adequate to fulfill the require- 
ment that at any given moment the crystalline rock shall exhibit but a 
slight strain effect. 
Of course, it is not thought probable that any rock has completely re- 
crystallized 50,000 times. Indeed, it is well known that many of the 
rocks in which recrystallization is complete, in so far as the finer particles 
are concerned, contain many larger particles which have not been com- 
pletely recrystallized or even granulated. Perhaps one of the best in- 
stances of this is furnished by the schist-conglomerates. The typical 
schist-conglomerates contain a crystalline schist matrix, embedded in 
