Ebbing and Flowing Weil. 379 
both methods proved successful, but the 
fexmer appeared to introduce air into the 
glass with more expedition than the latter did ; 
the difference here mentioned, may however 
depend entirely upon management and acci- 
dental circumstances. The experiment which 
I have now related, shews the foregoing 
objection to be of no moment; consequently 
the present theory of irregular reciprocation 
may be pronounced to stand upon a safe foun- 
dation, and unexceptionable principles. 
The observations which have been made 
on Mr. Swainston’s accidental discovery, ren- 
der an elaborate inquiry into the constitution 
of Giggleswick Well unnecessary. Nature 
may he easily supposed to have produced an 
apparatus in the side of the hill, possessing 
the mechanical properties of the reciprocating 
tub, and all the phenomena will follow ; 
which are so remarkable in this fountain. 
Let us imagine a reservoir to be -concealed 
from view under the rocks; into which the 
stream of a subterranean brook falls, and 
beats part of its contents into foam by agi- 
tation. Let this cavity be connected with 
the external or visible basin, by a narrow 
serpentine chink concealed in the interposing 
strata; and the reader must perceive without 
farther explanation, that this conduit will 
3B2 
