200 HISTORY OF THE 



formation ; the corals, as was said, dissolve in 

 acids, the sponges burn with an odour strongly 

 resembling that of burnt horn. We are left some- 

 what at a loss with regard to the precise manner 

 in which this multitude of cells, which at last as- 

 sume the appearance of a plant or flower, are 

 formed. If we may be led in this subject by ana- 

 logy, it is most probable that the substance of 

 coral is produced in the same manner that the 

 shell of the snail grows round it : these little rep- 

 tiles are each possessed of a slimy matter, which 

 covers its body, and this hardening, as in the 

 snail, becomes an habitation exactly fitted to the 

 body of the animal that is to reside in it ; several 

 of these habitations being joined together, form 

 at length a considerable mass, and as most ani- 

 mals are productive in proportion to their minute- 

 ness, so these multiplying in a surprising degree, 

 at length form those extensive forests that cover 

 the bottom of the deep. 



Thus all nature seems replete with life ; almost 

 every plant on land has its surface covered with 

 millions of these minute creatures, of whose exist- 

 ence we are certain, but of whose uses we are 

 entirely ignorant ; while numbers of what seem 

 plants at sea are not only the receptacles of in- 

 sects, but also entirely of insect formation. This 

 might have led some late philosophers into an 

 opinion, that all nature was animated ; that every, 

 even the most inert mass of matter, was endued 

 with life and sensation, but wanted organs to 

 make those sensations perceptible to the observer : 

 those opinions, taken up at random, are difficultly 



