LECTURE XII. 213 



which require a calm sea,, and thus another food 

 from the animal kingdom is presented to strangers. 

 The shallows also afford a quiet and desirable situ- 

 ation to Mollusca, and shell-fish of all kinds, and 

 contribute greatly towards supplying the inhabit- 

 ants ef the islands with a variety of food. Thus 

 we perceive that the Coral tribe, however insigni- 

 ficant it may at first appear, is one of those power- 

 ful engines in the hand of the Author of nature 

 which can produce the most stupendous effects from 

 the most seemingly weak and unpromising agents. 

 After this general survey of the Zoophyte tribe, 

 I shall beg leave to direct your attention to a Class 

 of Animals which, till the latter part of the seven- 

 teenth century, had escaped all human attention and 

 investigation, and constituted a kind of invisible 

 world : a series of beings, the structure, powers, 

 and properties of which, are perhaps more aston- 

 ishing than those of most other animals : yet of 

 such minuteness as, in general, to elude the sharp- 

 est sight, unless assisted by glasses. The ancients 

 therefore were totally unacquainted with this class 

 of beings. To them the Mite was made the nt 

 pivj ultra, or utmost bound of animal minuteness -, 

 but the moderns, assisted by the invention of the 



