80 BOUNDED KNOLLS AND BASINS. 



two of the localities within a short distance of otir route, 

 where cliffs of gypsum presented this mineral in exhaust- 

 less abundance, 



The most striking circumstance connected with these 

 extensive deposits of gypsum, where they occur near 

 the surface, is the singularly undulating character they 

 impart to the surface. Bound knolls, and equally round 

 pot-shaped hollows, perpetually occur, and give so charac 

 teristic an appearance to the district that an accustomed 

 eye will require little else to suggest the probable presence 

 of beds or masses of gypsum, wherever, in conjunction 

 with reddish soils, this appearance happens to be seen. 

 These cup-shaped hollows are sometimes of large dimen 

 sions hundreds of feet in diameter sometimes small 

 enough to be leaped across ; sometimes dry and covered, 

 as the rounded edges and knolls which separate them 

 from each other are, with a beautiful short, rich, green 

 herbage, or with trees of various kinds in vigorous 

 growth sometimes filled with water of great depth, and 

 forming even lakes of considerable size, with green 

 islands rising from them, loaded with luxuriant broad- 

 leaved trees. These hollows and round hills, and the 

 general aspect of the surface, are due to the sinking down 

 of the rain and other water at various places, where 

 cracks or fissures in the gypsum-rock allow it to descend, 

 and the consequent solution and washing out of the sub 

 stance of the gypsum-rock itself at these places. This 

 causes the surface to subside, and gradually to produce 

 the large and deep hollows and the rounded knolls, still 

 containing gypsum, which the country presents. The 

 most striking example I have seen of this kind of 

 appearance over a small space is in Sussex Vale, in New 

 Brunswick. I shall describe this spot in a subsequent 

 chapter. 



After dining at Amherst, where the traveller will find 

 a comfortable inn, we returned over the marsh-land we 



