604 



SCIENTIFIC RECREATIONS. 



pure when condensed from the clouds, absorbs carbonic acid, etc., from the 

 atmosphere. We have shown how this water as soon as it comes upon the 

 earth attacks the rocks, and as it progresses carries away lime. After 

 descending deep down, it rises again in the form of SPRINGS. 



Now what are these springs ? They are the result of percolation of 

 rain-water through certain strata. When water falls it is absorbed into the 

 ground, unless it happens to rest upon an impermeable rock, in which case 

 it becomes a rivulet. But it can penetrate between the atoms of many rocks, 

 and thus falls through sand and harder rocks, till it reaches a stratum 

 which will not receive it like clay. We then find that it will flow away in a 

 spring, or if tapped will be an Artesian well. These water-wells are of very 

 ancient date, but the name is more modern.* The springs flow out, and 



Fig. 691. Distribution ofland and water. 



develop, with the assistance of tributaries, into rivers. These again receive 

 more tributaries, which swell the volume of their waters, and widen out, carrying 

 millions of gallons hourly to the sea with sediment and gravel and stone. 



Water has enormous power of disintegration. We have only to cast 

 our eyes upon the illustrations in any volume of continental travel in Europe 

 or America to perceive the gorges and canons worn out by the resistless 

 and frequently gently-flowing river to estimate the part which water plays 

 in Physical Geography and Meteorology. 



But springs occur not only in the case mentioned ; there are mineral 

 springs, hot springs, and oil springs, all following the same rules of nature. 

 The Artesian well has been mentioned. The Geysers of Iceland have often 



* From Artois, where the first European well of this kind existed. 



