FEEDING THE SENSES. 75 



the mouth receives food and drink for repairing 

 the general waste of more rude and common parts 

 of the body ; and it is equally probable that the 

 immediate organs of all the other senses receive, 

 the same renewalfrom exercise; and that, as the eye 

 gets healthy, and fat, and vigorous, by beautiful 

 views, just so does the ear fatten upon sweet 

 sounds, and the nose upon grateful perfumes. We 

 must not be startled at the immeasurably small 

 quantity which is added, or passes from object to 

 organ in these cases, because, supposing that size 

 and weight are necessary for the accomplishment 

 of nature's purposes, and that the purpose effected 

 is in proportion to either of these, are among the 

 prejudices, against which we must especially guard. 

 In common materials, size and weight are so far 

 the measures of strength, but beyond a certain 

 extent they become weaknesses ; and there is an 

 elevation, and not a very high one, to which, if 

 reared, a tower would crush its foundations, though 

 of adamant, or a mountain reduce its granite to 

 dust. But, in all cases where there is natural 

 action, we must bear in mind that size and weight, 

 instead of being elements of that action, or assist- 

 ants to it, are clogs and hindrances, and probably 

 the only clogs and hindrances, by which it is re- 

 strained and diminished. It is, indeed, the same 

 in all action, whether natural or artificial. Ac- 

 tion is exactly the same thing with motion ; and 

 in all cases of change of matter, which is the only 

 evidence we can have of action, there is change 

 of place, though in many instances that change is 

 so small that we are unable to perceive it. When 

 brine, that is, water holding common salt dissolved 

 or in a liquid state, is boiled, and allowed to 

 H 2 



