422 Sir Humphry Davy on the relations , &c. 
Another application of importance which may be made, 
is the prevention of the wear of the paddles or wheels, 
which are rapidly dissolved by salt water. 
But I will conclude. Whenever a principle or discovery 
involves or unfolds a law of nature, its applications are almost 
inexhaustible ; and however abstracted it may appear, it is 
sooner or later employed for common purposes of the arts 
and the common uses of life. 
