OF GREAT BRITAIN. 55 



" At Encombe, in Dorsetshire, the seat of the 

 Earl of Eldon, there is an artificial pond of two or 

 three acres in extent facing the house. The pond 

 is paved with marble at the bottom and sides, and 

 is supplied with water from a small fountain fed 

 from a spring in the neighbouring valley, carried 

 by an artificial tunnel under some high hills. The 

 pond is, for all practical purposes, stagnant ; the 

 fountain's supply not being more than equivalent 

 to the summer evaporation . From 1862 to 1864 

 this pond was drained off and left absolutely dry, 

 in order to kill the weeds and clean the bottom. 

 In 1864 the water was turned in again, and in 

 August of that year a number of artificially reared 

 Trout of the same season's hatching, about three- 

 quarters of an inch long, were put into the pond. 

 In August, 1866, the pond was again dried for 

 cleansing purposes, when it was found that the 

 Trout had grown in the space of two years to an 

 amazing extent four or five pounds being the 

 smallest size, and a weight of six pounds ten ounces 

 having been attained in several cases. 



"When visiting at Encombe in September of 

 the following year, I examined the pond at Lord 

 Eldon's request, with a view to ascertaining to 

 what cause, in the absence of any artificial feeding, 

 the extraordinary growth-rate was to be attributed. 

 With the aid of a bucket and a rope, the explana- 

 tion was not hard to find : the whole pond was 

 simply swarming with water shrimps, and on ques- 



