34 M. Andre de Luc on the Ope>n?igs in Mountain-Chains 



the Alps, and has a long valley, that seems hewn out on pur- 

 pose to give its waters a passage amidst so many rocks and 

 mountains that are on all sides of it. This brings it almost in 

 a direct line to Geneva. It would there overflow all the coun- 

 try, were there not one particular cleft that divides a vast cir- 

 cuit of mountains, and conveys it off to Lyons. From Lyons 

 there is another great rent, which runs across the whole country 

 in almost another straight line, and, notwithstanding the vast 

 height of the mountains that rise about it, gives it the short- 

 est course it can take to fall into the sea. Had such a river 

 as this been left to itself, to have found its way out from among 

 the Alps, whatever windings it had made, it must have formed 

 .several little seas, and have laid many countries under water 

 before it had come to the end of its course." 



Similar reflections may be made on the Elbe at its depar- 

 ture from Bohemia. This river finds a deep passage across 

 the mountains which separate that country from Saxony. 

 This passage is a valley of surprising variety of aspects ; it 

 intersects an entire chain of mountains of very variable height. 

 The following are a few details respecting this passage, de- 

 rived from the geological travels of De Luc in Germany. 



At Aussig, De Luc remarked in a first range of mountains 

 a transverse opening, which aftbrded a passage to the Elbe, 

 and, after issuing from thence, the river all at once changed 

 its course nearly at a right angle, to follow the direction of 

 another valley. De Luc descended the Elbe from Tetschen 

 to Pirna in a boat. The course of the river serpentines be- 

 tween steep rocks, the correspondence of which presents all 

 the characters of a double fracture ; sometimes the strata of 

 these rocks descend towards the river, sometimes they mcline 

 in an opposite du-eetion. The mountains which border the 

 river are intersected by many valleys or combes, the sides of 

 which are abrupt. In one place the passage of the Elbe ap- 

 ears coompletely closed up ; in front of the observer rises a 

 steep mountain, but the river soon tm'ns to the right, and tra- 

 verses one gap, then a second, and finally issues from this 

 chain of mountains altogether. 



As we approach Pirna, the rocks on both sides become 

 lower, their declivities gentlex', and some of them are covered 



