NATURAL THEOLOGY. 83 



fusion, the validity of this example would remain 

 the same. If there were but one watch in the 

 world, it would not be less certain that it had 

 a maker. If we had never in our lives seen any 

 but one single kind of hydraulic machine, yet, if of 

 that one kind we understood the mechanism and 

 use, we should be as perfectly assured that it pro- 

 ceeded from the hand and thought and skill of a 

 workman, as if we visited a museum of the arts, 

 and saw collected there twenty different kinds of 

 machines for drawing water, or a thousand differ- 

 ent kinds for other purposes. Of this point each 

 machine is a proof independently of all the rest. So 

 it is with the evidences of a Divine agency. The 

 proof is not a conclusion which lies at the end of 

 a chain of reasoning, of which chain each instance 

 of contrivance is only a link, and of which, if one 

 link fail, the whole falls ; but it is an argument se- 

 parately supplied by every separate example. An 

 error in stating an example affects only that ex- 

 ample. The argument is cumulative, in the ful- 

 lest sense of that term. The eye proves it without 

 the ear ; the ear without the eye. The proof in 

 each example is complete ; for when the design of 

 the part, and the conduciveness of its structure to 

 that design is shown, the mind may set itself at 

 rest; no future consideration can detract any 

 thing from the force of the example. 



