48 NATURAL AND CIVIL 



began to flow. In the rocks at these falls, there 

 are several cavities, Avhich appear to have been 

 formed by the circular motion of small stones, 

 constantly kept in action by the force of the de- 

 scending waters. Some of these cavities arc 

 two or three feet in diameter, and from two to 

 four feet in depth ; and probably they are yet in- 

 creasing. Such phenomena are not uncommon 

 wherever there are deep falls in our rivers. 

 Bi;^ the most singular appearances of this na- 

 ture which I have ever seen, are at Cavendish, 

 upon Black river, near the house of Salmoi> 

 Dutton. Here, the channel of the river has 

 been worn down, one hundred feet ; And rocks 

 of very large dimensions, have been undermin- 

 ed, and thrown down, one upon another. Holes 

 are wrought into the rocks, of various dimen- 

 sions, and forms : Some of them are cylindrical, 

 from one to eight feet in diameter, and from 

 one to fifteen feet in depth : Others are of a 

 spherical form, from six to twenty feet diame- 

 ter, M^orn almost perfectly smooth, into the solid 

 body of a rock. 



How long a period nature has been employ- 

 ed in carrying on these operations, Ave can 

 scarcelj^ hope to determine. All the circum- 

 stances relating to the channels of rivers, and 

 the intervales which they liave formed, ai-e such 

 as denote periods of time very remote, and of 

 the highest antiquity. It can scarcely be sup^ 

 posed that in the formation of the intervales, the 

 annual increase has amounted to the tenth part 

 of an inch. At present, the freshets in the 

 spring and fall, and throughout the year, do not 

 ^ftfiually deposit the one laalf of this quantity of 



