[ 5 G 4 } [BookVIL 



CHAP. VII. 



HOT SPRINGS. 



PrcbaLle Cc>ufis of tl?efe f-henomena. Abound moft in volcanic Re- 

 gions. Hot Springs in Iceland, near Mount Hecla. At Geyfer. 

 Li the IJland of Ifcbici. At Viterbc. Explanation of tbefe Pheno- 

 mena. Burning Well in Lancafoire. Explained. 



THERE are few objects in natural hiftory, 

 which prefent: themfelves to our confideration, 

 accompanied with greater difEculties than thofe tepid 

 fprings, which exift in different parts of the world, 

 pf different degrees of temperature, and exhibiting 

 a variety of the moft curious phenomena. Many of 

 thefe have exifted as long as the earlieft records, and 

 for whole centuries have exhibited little variation in 

 their temperature. 



If any circumftance could ferve to fupport the 

 very dubious hypothefis of an immenfe refervoir of 

 fire in the center of the earth, it would be thefc 

 phenomena j yet there is but little reafon to fuppcfe 

 that the origin of thefe tepid fprings lies at any vaft 

 depth beneath the furface ; and, indeed, if we admit 

 the notion of a central fire, its effect ought to be more 

 general than it is found to be. The moft probable 

 nypothefis is, therefore, that the fame caufes operate 

 to produce thefe, which produce volcanoes i and the 

 only inference to be drawn from their permanent tem- 

 perature is, that the mafTes of matter, which produce 

 volcanic eruptions, may exift for a long feries of 

 time, even in a ftate of inflammation, without burfting 

 thole bandages with which nature has confined them ; 

 arid that heat may long be continued to a confiderable 



degree 



