157 
water course, for on each side of the rivulet we find the same 
formations, as though no doubt there were once continuity in 
structure and unbroken surface. 
Such is the destroying and transporting agency of atmos- 
pheric waters. 1st, in consuming away the sohd substance of 
the rocks ; and 2ndly, in conveying the detached fragments, 
mechanically suspended, from one part of the earth to another 
at a lower level, and ultimately to the sea. 
Springs, being impregnated with foreign ingredients, deriv- 
ed from the strata and soils through which they pass, serve to 
augment this perpetual process in a two-fold manner; 1st, by 
their volume and gravity, and 2ndly, by their carrying off 
various mineral matters, which, being in a state of solution, 
are not, except by analysis, discernible. 
The source of the water of springs is usually the filtration 
of rain through the loose alluvial soils and cracked joints of 
rocks. Having arrived at the water-bearing level so far on 
its vertical descent, it commences an horizontal course, and 
after having traversed the loosely laminated surfaces and 
fissures of continuous strata, it is again, either by a disloca- 
tion, or (as more commonly occurs with the springs of this 
parish) by meeting with softer argillaceous deposits on the 
sloping sides of the hills from breach of contiguity of strati- 
fication, thrown out by gravity, and the vis a tergo, upon 
the surface charged with saline ingredients from what has 
proved soluble in its tortuous subterranean course. 
The loose soils, beds of gravel, and porous ragstone of 
this neighbourhood, readily absorb water, which descends 
until its downward progress is arrested by a stratum of clay, 
compact sandstone, or some other impermeable material, 
where it accumulates, forming a subterranean sheet of water, 
beneath which bearing level, practical well-sinkers know there 
is no occasion to go for a permanent supply of this fluid : in- 
deed, it is seldom necessary to sink so far. 
