water, then their depth at the centre need never be more 

 than from three to five feet, shelving to the sides as before 

 stated; but if only an indifferent supply can be obtained, 

 then they must be twelve or eighteen inches deeper. 



It is not, however, desirable to have the ponds so situated 

 that a large quantity of fresh water shall suddenly be able 

 to find its way into them, as it both thickens the whole by 

 moving the mud, and being colder and of other properties, 

 it sickens the store for some time and checks their thriv- 

 ing. A well-regulated supply and co-equal discharge is to 

 be recommended and must be attended to. 



Having thus far described the base and positions which 

 the ponds ought to have, I shall proceed to lay down the 

 requisite rules, by attention to which a lucrative rental can 

 be obtained, where an estate is adapted for succession 

 ponds. The first pond should be the smallest of the three, 

 the second next in size, and the third the largest, for the 

 following reasons. At the period of fishing, as before stated, 

 a great portion of the brood escapes with the flood, which 

 cannot be prevented ; and as another year must elapse be- 

 fore the water or pond in succession can be fished, too much 

 of the food of the original store would be consumed were 

 not the second pond larger, and so capable of receiving the 

 addition ; it would moreover prove extremely detrimental, 

 as I shall afterwards show. 



In order to come to the dimensions of the ponds I shall 



