58 HISTORY OF 



into boats that lie on the brink of the river 

 Maese. This quarry is so large, that forty thou- 

 sand people may take shelter in it : and it in ge- 

 neral serves for this purpose, when armies march 

 that way ; becoming then an impregnable retreat 

 to the people that live thereabout. Nothing can 

 be more beautiful than this cavern, when lighted 

 up with torches ; for there are thousands of square 

 pillars, in large level walks, about twenty feet 

 high ; and all wrought with much neatness and 

 regularity. In this vast grotto there is very little 

 rubbish ; which shows both the goodness of the 

 stone, and the carefulness of the workmen. To 

 add to its beauty, there also are, in various parts 

 of it, little pools of water, for the convenience 

 of the men and cattle. It is remarkable, also, 

 that no droppings are seen to fall from the roof, 

 nor are the walks any way wet under foot, except 

 in cases of great rains, where the water gets in 

 by the air-shafts. The salt-mines in Poland are 

 still more spacious than these. Some of the cata- 

 combs, both in Egypt and Italy, are said to be 

 very extensive. But no part of the world has a 

 greater number of artificial caverns than Spain, 

 which were made to serve as retreats to the Chris- 

 tians, against the fury of the Moors, when the 

 latter conquered that country. However, an ac- 

 count of the works of art does not properly be- 

 long to a natural history. It will be enough to 

 observe, that though caverns be found in every 

 country, far the greatest part of them have been 

 fashioned only by the hand of nature. Their 

 size is found beyond the power of man to have 



