TIME AND CHANGE 
transmutations they have undergone! They have 
passed through Nature’s laboratory and taken on 
new forms and characteristics. 
‘All sediments deposited in the sea,” says my 
geology, ‘‘undergo more or less chemical change,” 
and many chemical changes involve notable changes 
in volume of the mineral matter concerned. It has 
been estimated that the conversion of granite rock 
into soil increases its volume eighty-eight per cent, 
largely as the result of hydration, or the taking up of 
water in the chemical union. The processes of oxid- 
ation and carbonation are also expansive processes, 
Whether any of this gain in volume is lost in the pro- 
cess of sedimentation and reconsolidation, I do not 
know. Probably all the elements that water takes 
from the rocks by solution, it returns to them when 
the disintegrated parts, in the form of sediment in the 
sea, is again converted into strata. It is in this cycle 
of rock disintegration and rock re-formation that 
the processes of life go on. Without the decay of the 
rock there could be no life on the land. Water and 
air are always the go-betweens of the organic and 
inorganic. After the rains have depleted the rocks 
of their soluble parts and carried them to the sea, 
they come back and aid vegetable life to unlock and 
appropriate other soluble parts, and thus build up 
the vegetable and, indirectly, the animal world. 
That the growth of the continents owes much to 
the denudation of the sea-bottom, brought about by 
106. 
