Geology and Natural History. 165 



the great resistance against the liquid permeating upwards 30 or 

 40 kilometers through interstices among the solid granules, this 

 process must have gone on somewhat slowly ; and, during all the 

 time of the shoaling of the larva ocean, there may have been a 

 considerable proportion of the whole volume occupied by the 

 mother liquor among the solid granules, down to even as low as 

 50 or 100 kilometers below the top of the heap, or bottom of the 

 ocean, at each instant. When consolidation reached the surface, 

 the oozing upwards of the mother liquor must have been still 

 going on to some degree. Thus, probably for a few years after 

 the first consolidation at the surface not probably for as long as 

 one hundred years, the settlement of the solid structure by mere 

 mechanical crushing of the corners and edges of solid granules, 

 may have continued to cause the oozing upwards of mother liquor 

 to the surface through cracks in the first formed granite crust and 

 through fresh cracks in basaltic crust subsequently formed 

 above it." 



After a further discussion of the probable origin of continents 

 and ocean depths, and also of the earth's atmosphere, the author 

 concludes as follows : 



" 43. Whatever may have been the true history of our atmo- 

 sphere it seems certain that if sunlight was ready, the earth was 

 ready, both for vegetable and animal life, if not within a century, 

 at all events within a few hundred centuries after the rocky con- 

 solidation of its surface. But was the sun ready? The well 

 founded dynamical theory of the sun's heat carefully worked out 

 and discussed by Helmholtz, Newcomb, and myself,* says NO if 

 the consolidation of the earth took place as long ago as 50 mil- 

 lion years; the solid earth must in that case have waited 20 or 50 

 million years for the sun to be anything nearly as warm as he is 

 at present. If the consolidation of the earth was finished 20 or 

 25 million years ago, the sun was probably ready, — though prob- 

 ably not then quite so warm as at present, yet warm enough to 

 support some kind of vegetable and animal life on the earth." 



" § 44. My task has been rigorously confined to what, humanly 

 speaking, we may call the fortuitous concourse of atoms, in the 

 preparation of the earth as an abode fitted for life, except in so 

 far as I have referred to vegetation, as possibly having been con- 

 cerned in the preparation of an atmosphere suitable for animal 

 life as we now have it. Mathematics and dynamics fail us when 

 we contemplate the earth, fitted for life but lifeless, and try to 

 imagine the commencement of life upon it. This certainly did 

 not take place by any action of chemistry, or electricity, or crys- 

 talline grouping of molecules under the influence of force, or by 

 any possible kind of fortuitous concourse of atoms. We must 

 pause, face to face with the mystery and miracle of the creation 

 of living creatures." 



*See "Popular Lectures and Addresses," vol. i, pp. 376-429, particularly page 

 397. 



