NATURAL THEOLOGY. 37 



appropriate, or more mechanical ? If it be over- 

 looked by the observer of nature, it can only be 

 because it is obvious and familiar. This is a ten- 

 dency to be guarded against. We pass by the plain- 

 est instances, whilst we are exploring those which 

 are rare and curious ; by w4iich conduct of the 

 understanding, w^e sometimes neglect the strong- 

 est observations, being taken up w4th others w^hich, 

 though more recondite and scientific, are, as solid 

 arguments, entitled to much less consideration. 



In order to keep the eye moist and clean (which 

 qualities are necessary to its brightness and its use,) 

 a wash is constantly supplied by a secretion for the 

 purpose ; and the superfluous brine is conveyed to 

 the nose through a perforation in the bone as 

 large as a goose-quill. When once the fluid has 

 entered the nose, it spreads itself upon the inside 

 of the nostril, and is evaporated by the current of 

 warm air which, in the course of respiration, is con- 

 tinually passing over it. Can any pipe or outlet, 

 for carrying off the waste liquor from a dye-house 

 or a distillery, be more mechanical than this is ? It 

 is easily perceived that the eye must want moisture : 

 but could the w^ant of the eye generate the gland 

 which produces the tear, or bore the hole by which 

 it is discharged — a hole through a bone ? 



It is observable that this provision is not found 

 in fish — the element in which they live supplying 

 a constant lotion to the eye.'^ 



" We have entered into a much fuller explanation of the appa- 



4 



