and originall of a hot Bath, one[errata 1] the cleareſt and beſt account that I ever heard or read, of the cauſe of the heat in Bathes is that which is given by Mounſieur de Rochas, & that in a demonſtrative way; His words are theſe. As I was (ſaith he) with ſome of my companions wandring in Savoy, I ſound in the valley of Luzerne betwixt the Alps a hot ſpring; I began to conſider the cauſe of this heat, and whereas the vulgar opinion is that the heat of fountains is from mountains fired within, I ſaw reaſon to think the contrary, because I ſaw ſnow upon a mountaine from whence this hot ſpring came, unmelted, which could not have poſſibly but have been diſſolved by the hot fumes of the mountains, had they been fired. Whereupon being unſatisfied I with my companions and other labourers (whom I could very hardly perſwade to undertake ſuch a buſineſſe by reaſon they were afraid that fire would thereupon break forth out of the ground and conſume us) got tools and ſet upon digging to ſind out the true cauſe of the heat of this fountain. After we had digged 15. dayes (having before perceived the water to be hotter and hotter by degrees as we came neerer to the ſource) we came to the originall of the heat, where was a great ebullition: In three houres more we digged beyond this place of ebullition and perceived the water to be cold, yet in the ſame continued ſtream with the other that was hot: upon this I began to wonder much at the reaſon of theſe things. Then I carryed to my lodging ſome of this hot water (which was both ſaltiſa, and acid) and evaporated it, and of forty ounces I had in the bottome five drans of ſaltiſh matter, which I then yet ſarther purified, and extracted thence three drams of pure nitrous Hermetick ſalt, the other two ounces being a ſlimie ſulphurous ſubſtance. Yet with this I was not ſatisfied, but with my labourers went again to the place, and digged twelve daies more, and then we came to a water which was inſipid as ordinary fountain Water, yet ſtill in a continued ſtream with the ſaltiſh and hot water. At this I wondred much, whereupon I digged up ſome of the earth where the cold, and ſaltiſh ſtreame runned, & carried it home with me, and out of a hundred weight thereof, I extracted a good quantity of nitrous ſalt, which was
- ↑ Correction: one should be amended to now
