WHY BO SFEINGS AND WELLS OVERFLOW? 401 



stracted from the summer and autumn supplies of the river Colne." 

 Hence, even if the -wells in Germany were, as stated rather strongly 

 by Mr, Green, "a new and important source of supply to the rivers 

 themselves," it would not alter the fact, shown by experiment, that 

 the proprietors of mills on the river Colne, and the owners of adjacent 

 water-meadows, would have been robbed of rights which they had 

 inherited from time immemorial, by drawing the water-supply of the 

 great city of London from wells in the chalk formations of Hertford- 

 shire, 



But Mr, Green's two propositions that differ most essentially from 

 the commonly accepted theory of artesian wells are — 1, That the flow 

 of water from them is not due to pressure transmitted from water at a 

 higher level, but to " some force not yet identified " ; and, 2. That the 

 supply of water for such wells, and indeed for ordinary springs, comes 

 from " subterranean waters, seldom if ever influenced by rains " (p. 75, 

 line one), Mr, Green identifies the required force as " the resultant 

 of the earth's centripetal and centrifugal forces," and, having found 

 that the tendency of this resultant is to force water iip, wherever 

 there is an opening upward in the earth's crust, of course it is neces- 

 sary to suppose that there is a plenty of subterranean water already 

 down. He seems to think it entirely unnecessary to suggest any 

 means of replenishing the supply of this subterranean water, or even 

 to imagine that it could ever need replenishing. 



Listen to Mr, Green : " Imagine the ' majestic column ' at Grenelle 

 rising thirty feet high, and the overflow in the other cases being due 

 to hydrostatic pressure — i. e,, due to the fact that all these immense 

 floods were the result of a flow from some other higher bodies of water." 

 Ordinary people will find it as easy to imagine this as to suppose that 

 these floods are the result of flow from loioer bodies of water uncon- 

 nected with higher ones. But he goes on : " Why did it not occur to 

 Professor Buckland that, however high and abundant the source, such 

 drains must of necessity have sooner or later exhausted the supply, if 

 no equivalent streams were flowing into that also ? But suppose this " 

 {sic) " to be so, whence could come the higher head to flow into and 

 supply that in turn ? Carry this on until a flow is secured from the 

 highest land on the earth, and then whence comes the flow to supply 

 that ? " This is beautiful. Why did it not occur to Mr. Green that, 

 however loic and abundant the source, such drains must of necessity 

 have sooner or later exhausted the supply if no equivalent streams 

 were flowing into that also ? But suppose this to be so, whence could 

 come the loicei^ head to flow into and supply that in turn ? Carry this 

 on until a flow is secured from the center of the earth, and then where 

 are you ? 



In another place (p. 81) Mr. Green says : " Suppose it had been fulli/ 

 proved that a particular overflowing spring was caused by hydrostatic 

 pressure, it would still remain to be accounted for how the water 

 VOL. XVI. — 26 



