Lesley.] 4Q0 [June. 



surface water, which penetrates all its formations, and descends step 

 by step to a depth, which is probably limited by the horizon of 

 radiant heat equal to 100° C, that is, to a depth of at least two 

 miles. At various stages the descending percolation, aided by a 

 universal fissure and crevasse system, forms water horizons and re- 

 servoirs, subject to enormous hydraulic pressure, reproducing the 

 water at the surface, either through natural springs or artificial wells. 

 It is not too much to say, then, that 20 per cent, of the crust of the 

 earth, to a depth of two miles, consists of disseminated and collected 

 water. This will take into account condensation descending. 



What, then, was the case in early days when the horizon of 100° 

 C. was at the surface ? We must conclude that all this water was at 

 that time excluded from the crust, and compelled to remain above 

 the surface as heated ascending aqueous vapor, and descending rain ; 

 and, of course, keeping the general sea-level higher than at present. 



Taking the mean density of all rocks near the surface at 3 00, the 

 20 per cent, of water contained in a stratum of crust two miles deep, 

 will represent more than six hundred feet of water in mass; and, 

 taking; one-third of the earth's surface as land, and confinins; the 

 desiccation to the land surface alone, we have an elevation of the 

 general level of the other two-thirds, or ocean-surface of the planet, 

 equal to four hundred feet ; enough to submerge a considerable per- 

 centage of the area of each one of the existing continents. 



Pending nominations Nos. 522, 523, 524, and new nomi- 

 nation No. 525, were read. 



On motion of the Librarian, seconded by Dr. Coates, it was 

 ordered, that copies of Part I of the Catalogue be sent with 

 Part I, Volume XIII, of the Transactions, in the next distri- 

 bution, to Corresponding Societies which receive the Transac- 

 tions. 



And the Society was adjourned. 



