48 HISTOllY OF 



Others that descend but a little way, and then spread theniseivca 

 often to a great extent below the surface. Many of these 

 caverns, it must be confessed, may be the production of an 

 and human industry ; retreats made to protect the oppressed, 

 or shelter the spoiler. The famous labyrinth of Candia, for in- 

 stance, is supposed to be entirely the work of art. Mr Tourne- 

 fort assures us, that it bears the impression of human industry 

 and that great pains have been bestowed upon its formation. 

 The stone-quarry of Maestricht is evidently made by labour ; 

 carts enter at its mouth, and load within, then return, and dis- 

 charge their freight into boats that lie on the brink of the river 

 Maese. This quarry is so large, that forty thousand people 

 may take shelter in it : and it in general 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 catacombs, 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 Christians against the fury of 

 the Moors, when the latter conquered that country. However, 

 an account of the works of art does not properly belong to a na- 

 tuial histor)'. It will be enough to observe, that though caverns 

 be found in every country, far the greatest part of them have 

 been fashioned by the hand of nature only. Their size is found 

 beyond the power of man to have effected, and their forms but 

 ill adapted to the conveniences of a human habitation, in 

 some places indeed, we find mankind still make use of th.ena 



1 Plijl. TrauB. Tol. ii. p. 363. 



