TEKEDO NAVALIS. 377 



gular fact of their generally boring iu the direction of the 

 grain. 



Teredines abound in Holland, where the great rivers are 

 held up by dykes at the height of twenty or even tliirty feet 

 above the level of the land. Here the Teredines frequently 

 work their way into the wooden piles, which sustain these 

 important barriers, and threaten their total demolition, if 

 the precaution of sheathing their sides with copper, or a 

 composition of tar and glass, has been neglected. During 

 the year 1731, considerable apprehensions having been 

 excited on this subject, persons were appointed by the 

 Dutch Government to examine into their state. On drawing 

 up one which had been driven in rather more than twenty 

 years previously, it was found, though apparently sound on 

 the outside, to be completely perforated within by innume- 

 rable Teredines J some of which exceeded a foot in length. 



All the various parts of nature are beautifully designed 

 to act in concert. In various instances, tlie lower we de- 

 scend in the chain of creation, the more obvious are the uses, 

 and the more extraordinary the instincts, of many of 

 the links which compose it. Providence has mercifully 

 provided that such should be the case ; and the reason is 

 clear : for, if the destructive and congregating propensities 



