RATS, 4S 



*taln. The former I am inclined to believe to be 

 the case in this state, but of this I am not certain. 

 The waters of these western streams have a self- 

 puddling power. Thej^ are saturated with lime, 

 gypsum, and vegetable and mineral decomposi- 

 tions, and their depositions will gradually fill up 

 the leaks and fissures in the canal. You know- 

 that a canal has been cut through the bog of Allan 

 in Ireland at an inunense expense, and which is 

 perfectly water tight. The comparative facility 

 of making the western canal in the worst places is 

 obvious. The freshets of spring and autumn— 

 the heavy rains and snows of winter — and the 

 operations of frost, have exhausted, the last season, 

 all their powers against this communication, and 

 it has stood the shock at a trifling expense. In 

 some places there is quick sand, which ever shift- 

 ing and sliding, requires strong protection against 

 Its ravages. 



I presume you know that moles and rats are so 

 injurious to canals in England, that rat catchers 

 are employed to extirpate them. I have seen 

 already in some places the holes of these animals ; 

 I do not know whether the brown, gray, or Nor- 

 way rat, the mus decumanus of Linnaeus and mus 

 sylvestris of Pennant, or the black rat, mus rattus 

 of Linnaeus, have extended their migrations as far 

 as this part of the country. They both follow 



