THE EARTH. 



19 



CHAPTER VH. 



OF CAVES AND SUBTERRANEOUS PASSAGES THAT SINK, BUT NOT PER- 

 PENDICULARLY, INTO THE EARTH. 



IN surveying the subterranean wonders of 

 the globe, besides those fissures that descend 

 perpendicularly, we frequently find others 

 that descend but a little way, and then spread 

 themselves often to a great extent below the 

 surface. Many of these caverns, it must be 

 confessed, mny be the production of art and 

 human industry; retreats made to protect the 

 oppressed, or shelter the spoiler. The fa- 

 mous labyrinth of Candia, for instance, is 

 supposed to be entirely the work of art. Mr. 

 Tournefort assures us, that it bears the im- 

 pression of human industry, and that great 

 pains have been bestowed upon its formation. 

 The stone-quarry of Maastricht is evidently 

 made by labour: carts enter at its mouth, 

 and load within, then return, and discharge 

 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 drop- 

 pings 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 ca- 



a Phil. Trans, vol. ii. p. 368. 

 NO. 3. 



verns that 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 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 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 them as houses; particularly in 

 those countries where the climate is very se- 

 vere;" but in general they are deserted by 

 every race of meaner animals, except the 

 bat : these nocttirnal solitary creatures are 

 usually the only inhabitants ; and these only 

 in such whose descent is sloping, or, at least, 

 not directly perpendicular. 



There is scarcely a country in the world 

 without its natural caverns; and many new 

 ones are discovered every day. Of those in 

 England, Oakey-hole, the Devil's-hole, and 

 Penpark-hole, have been often described. 

 The former, which lies on the south side of 

 Mendip-hills, b within a mile of the town of 

 Wells, is much resorted to by travellers. To 

 conceive a just idea of this, we must imagine 

 a precipice of more than a hundred yards 

 high, on the side of a mountain which shelves 

 away a mile above it. In this is an opening 

 not very large, into which you enter, going 

 along upon a rocky uneven pavement, some- 

 times ascending, and sometimes descending. 

 The roof of it, as you advance, grows higher; 

 and, in some places, is fifty feet from the 

 floor. In some places, however, it is so low, 

 that a man must stoop to pass. It extends 

 itself, in length, about two hundred yards: 

 and from every part of the roof and the floor, 

 there are formed sparry concretions of various 



b Phil. Traus. vol. ii. p. 368. 

 G 



