92 NATURAL THEOLOGY. 



add to this argument examples without number. 

 Of all large terrestrial animals the structure is 

 very much alike ; their senses nearly the same ; 

 their natural functions and passions nearly the same ; 

 their viscera nearly the same, both in substance, 

 shape, and office : digestion, nutrition, circulation, 

 secretion, go on in a similar manner, in all ; the great 

 circulating fluid is the same ; for, I think, no differ- 

 ence has been discovered in the properties ofblood, 

 from whatever animal it be drawn. The experi- 

 ment of transfusion proves that the blood of one 

 animal will serve for another. The skeleton also 

 of the larger terrestrial animals show particular 

 varieties, but still under a great general affinity. 

 The resemblance is somewhat less, yet sufficient- 

 ly evident, between quadrupeds and birds. They 

 are all alike in five respects, for one in which they 

 differ. 



In fah, which belong to another department, as 

 it were, of nature, the points of comparison be- 

 come fewer. But we never lose sight of our ana- 

 logy, €. g. we still meet with a stomach, a liver, a 

 spine; with bile and blood; with teeth; with eyes, 

 (which eyes are only slightly varied from our Ovvn, 

 and which variation, in truth, demonstrates, not an 

 interruption, but a continuance of tlie same exquisite 

 plan ; for it is the adaptation of the organ to the ele- 

 ment, viz. to the different refraction of light passing 

 into the eye out of a denser medium.) The provin- 

 ces, also, themselves of water and earth, are con- 

 nected by the species of animals which inhabit 



