570 HYDRAULIC ADJUSTMENTS. 
nomy of the Globe, we may further include the 
circumstance, that these fractures are the most 
frequent channels of issue to mineral and ther- 
mal waters, whose medicinal virtues alleviate 
many of the diseases of the Human Frame.* 
" Thus in the whole machinery of Springs and 
Rivers, and the apparatus that is kept in action 
for their duration, through the instrumentality 
of a system of curiously constructed hills and 
valleys, receiving their supply occasionally from 
the rains of heaven, and treasuring it up in their 
everlasting storehouses to be dispensed perpetu- 
ally by thousands of never-failing fountains, we 
see a provision not less striking, than it is 
important. So also in the adjustment of the 
relative quantities of Sea and Land, in such due 
proportions as to supply the earth by constant 
evaporation, without diminishing the waters of 
the ocean ; and in the appointment of the Atmos- 
phere to be the vehicle of this wonderful and 
unceasing circulation ; in thus separating these 
waters from their native salt, (which though of 
the highest utility to preserve the purity of the 
* Dr. Daubeny has shewn that a large proportion of the 
thermal springs with which we are acquainted, arise through 
fractures situated on the grreat lines of dislocation of the strata. 
See Daubeny on Thermal Springs, Edin. Phil. Jour. April, 
1832, p. 49. 
Professor Hoffman has given examples of these fractures in 
the axis o^ valleys of elevation, through which chalybeate waters 
rise at Pyrmont, and in other valleys of Westphalia. See PI. 
67, fig. 2. 
