6o6 



SCIENTIFIC RECREATIONS. 



the Artesian principle. 



Fig. 693 Colorado Canon (effects of water erosion). 



compare with any in the world 

 we will now consider briefly. 



The petroleum is bored for, as we bore for water, 

 and the oil rushes up with great force, 

 and in enormous quantities. Gas wells 

 are also to be found in Pennsylvania, 

 and have supplied towns with gas for 

 years. Both these Artesian wells are 

 caused by the decay of vegetation. 

 The gas is in the coal formation, and the 

 oil has been pressed out from vegetable 

 deposit, and as anthracite is a stony coal, 

 petroleum is a kind of coal-tar, of natural 

 formation. 



We have alluded to the river, which 

 emerges from the spring, which has fallen 

 as rain. But there is another, and, to 

 many minds, a much more interesting form 

 of the universal fluid we call water. This 

 is ice. Familiar as ice is, either to the 

 stay-at-home invalid, the skater, and the 

 traveller, there is a great deal to be said 

 about it. It is a subject we would dwell 

 upon had we space, for the remembrance 

 of many a pleasant hour passed upon 

 snow and glacier call upon us to go back 

 again, even though only in imagination. 

 No one who has not climbed the glacier 

 even the Mer de Glace to the Jardin, 

 now such a common excursion can fail to 

 be struck with the beauty and grandeur of 

 the scene presented to him, and to carry 

 away a fond recollection of the icy regions 

 he penetrated. 



For the ordinary hard-working man 

 there is no change, no rest so truly bene- 

 ficial as a trip amongst the mountains and 

 snowfields of Europe. He need not be a 

 climber ; that is, a climber like Tyndall 

 or Whymper, those giants of the Alpine 

 Club. But a stroll up to the Bel Alp, the 

 ^Eggishhorn, the RiffeJ, the Mon tan vert, or 

 the Grimsel, will give the average pedes- 

 trian some of the finest glacier scenery 

 in Europe, and which may, we believe, 

 for beauty. These glaciers ice-rivers 

 We may take the Mer de Glace as an example 



