THE EARTH. 75 



Nor are these vapours, which thus escape to 

 the surface of the earth, entirely unconfined ; for 

 they are frequently, in a manner, circumscribed 

 to a spot. The grotto Del Cane, near Naples, is 

 an instance of this ; the noxious effects of which 

 have made that cavern so very famous. This 

 grotto, which has so much employed the atten- 

 tion of travellers, lies within four miles of Naples, 

 and is situated near a large lake of clear and 

 wholesome water. * Nothing can exceed the 

 beauty of the landscape which this lake affords ; 

 being surrounded with hills covered with forests 

 of the most beautiful verdure, and the whole 

 bearing a kind of amphitheatrical appearance. 

 However, this region, beautiful as it appears, is 

 almost entirely uninhabited; the few peasants 

 that necessity compels to reside there, looking 

 quite consumptive and ghastly, from the poison- 

 ous exhalations that rise from the earth. The 

 famous grotto lies on the side of a hill, near 

 which place a peasant resides, who keeps a num- 

 ber of dogs, for the purpose of shewing the ex- 

 periment to the curious. These poor animals al- 

 ways seem perfectly sensible of the approach of 

 a stranger, and endeavour to get out of the way. 

 However, their attempts being perceived, they 

 are taken and brought to the grotto ; the noxious 

 effects of which they have so frequently expe- 

 rienced. Upon entering this place, which is a 

 little cave, or hole rather, dug into the hill, about 

 eight feet high and twelve feet long, the observer 



* Kircher, Mund. Subt. vol. i. p. 1 91 . 



