Contents xv 



Alkaline salt is shown to exist in quicklime, p. 154. Also 

 an acid salt, p. 155. Why quicklime does not become hot 

 when it is wet with spirit of wine or with any sulphureous 

 liquid, p. 156. Whence the contrary salts of lime arise, p. 

 157. Why these salts of quicklime do not effervesce unless 

 it is wet with water, p. 158. Why the contrary salts con- 

 tained in the water in which quicklime has been slaked do 

 not mutually destroy each other completely, p. 160. Of the 

 combination of contrary salts, p. 160. When they are mixed 

 they do not completely destroy each other, p. 160. The 

 spirit of nitre is shown to be a volatile acid salt, p. 161. 

 How a kind of vitriolated tartar can be produced from 

 nitre, p. 162. Acid salts seek union with metals, p. 162. 

 Alkaline salt combines with sulphur, p. 162. It is shown that 

 there is no acid salt in sulphur, p. 163. Salts of different 

 kinds should not rashly be included in the same prescription, 

 p. 164. The contrary salts of quicklime will not enter into 

 a closer union, p. 165. In what case contrary salts can come 

 together without the production of any ebullition, p. 167. 

 Why liquids become turbid by reason of precipitation taking 

 place in them, p. 168, Why quicklime added to lye makes 

 it more sharp, p. 169. 



CHAPTER XV.— Of the Thermal Waters of Bath. 

 Incidentally, of the Source of Springs. 



On the constituents of the said hot springs, p. 170. They 

 are charged with salts of an acid-saline character, p. 171. 

 It is shown that there is no nitre in the said hot springs, 

 p. 171. Nor is there sulphur dissolved in their water, p. 

 171. Not only so, but the water does not dissolve sulphur 

 when boiled with it, p. 172. Nor do these hot springs con- 

 tain sal armoniac, p. 173. Whether vitriol is contained in 

 the water or not, p. 174. It contains some metallic mineral 

 which, on the addition of an acid, is converted into vitriol, 

 p. 174. Whence comes the heat of the hot springs, p. 175. 

 It does not seem to have its origin in subterranean fire, p. 

 175. Biit from fermentation excited in the depths of the 

 earth, p. 175. On the origin of springs, p. 175. They do 



