VIVAEIA. 41 



dug down about nine feet, and the conduit pipes placed 

 about two feet from the top ; they should be as capa- 

 cious as possible, to admit sudden flushes of water, which 

 will help the issue of the stagnant mass lying below the 

 sea's level. Here it would be absurd to make those re- 

 cesses and alcoves spoken of above, and always to be 

 practised under favourable conditions : the water here 

 is all too still already, and the further it is drawn out 

 from the source of supply, the more stagnant will it be- 

 come, and thus more harm will accrue to its scaly inha- 

 bitants from putrid water suffered to remain, than any 

 conceivable degree of good from the cover' it may offer 

 against the heat, ' plus nocet putris unda, quam prodest 

 opacitas/ In providing for the issue of the water from 

 the pond, the 'exundation' is best effected by means of 

 a brass grating, with apertures of a size sufficiently great 

 to let it run freely out, but too small to allow the escape 

 of the young fish. If the dimensions of the pond per- 

 mit, it is no bad practice to remove fragments of rock, 

 covered with seaweed, from the neighbouring shore, 

 and to scatter them here and there in these little enclo- 

 sures, in imitation of the open sea. As the gites of fish 

 are very various, some lying on a bed of sand, some am- 

 bushed in mud, others feeding among rocks, your pond 

 should be constructed according to the character of the 

 sea in the neighbourhood; and finally, when the work 

 is completed, a series of stakes should be planted in a 

 semicircular form round that part of it which lets in the 

 water. These must be placed above the level of the 

 waves, so closely as to break the force of the impinging 

 waters, and to keep out the wrack and weeds which 

 would soon else fill the piscina. Having thus constructed 

 and secured the pond against casualties, the next point 

 should be to stock it wisely ; for as on land all fields 

 will not bear the same crops, just so is it in the vast 

 acreage of waters ; we must not think, for instance, be- 



