Chap. 6.] [ 491 ] 



CHAP. VI. 



OF SPRINGS AND RIVERS. 



Origin cf Springs. Digging cf Wells. Nature of Springs. Marjkej. 

 Cheap and eajy Mode of draining them.'~~Intermiiting Sfrings.-f 

 Rivers. Their Source, &c. 



THE water which falls on the furface of the earth, 

 in rain, fnow, &c. penetrates its'fubfrance till it 

 meets with a ftratum of clay, (lone, or fomc other 

 matter which flops its defcent ; it then glides laterally 

 on the ftratum which fuftains it, and in the direction 

 to which it leans, till meeting with an aperture, it ap- 

 pears on the furface of the earth in the form of a 

 ifpring. As water always has a tendency to defcend, 

 fprings are always lower than the fource from which 

 they are fupplied ; fprings are mod common on the 

 fides and at the bottom of mountains ; they are fel- 

 dom found quite at the fummit of a mountain, and are 

 rare where a country is every where level to a confi- 

 derable diftance, becaufe there the flrata are parallel, 

 and do not conduct the water to any particular point. 

 In order to obtain water, therefore, in flat countries, 

 it is in general neceflfary to dig into the earth, when it 

 is found to flow copioufly from the fides of the open- 

 ing, at no great diftance from the furface. Whea wells 

 are dug in elevated fituations, water is feldom met 

 with till we have dug to a confiderable depth, and got 

 below the general level of the country. 



A curious circumftance occurs in the making of 

 wells at Modena and Stiria in Italy. The workmen 

 begin by digging through feveral ftrata or foils, till 



they 



