96 THE OYSTER. 



Many methods of doing this have been devised and 

 employed, and the possibility of increasing the area 

 and value of the natural beds, and of building up new 

 beds, or restoring old ones, in this way has been proved. 



As this is by far the most important aspect of the 

 oyster problem, I shall devote considerable space to 

 the history of these experiments, and to a description 

 of the means and apparatus which have been employed 

 for the purpose. 



Although the development of this industry on a 

 large scale is quite modern, seed oysters for planting 

 have been raised artificially upon a small scale in Italy 

 for more than a thousand years, by a very simple 

 method. 



Pliny tells us that the artificial breeding of oysters 

 was first undertaken by a Roman knight, Sergius 

 Grata, in the waters of Lake Avernus, and that the 

 enterprise was so successful that its director soon be- 

 came very rich. 



At the present day the methods which were intro- 

 duced, and probably invented by Grata, are still em- 

 ployed by the oyster cultivators of Lake Fusaro, a 

 small salt-water lake. Upon the deep, black mud of 

 the lake they have constructed here and there heaps of 

 rough stones, high enough to keep them above the mud 

 and slime ; upon these rocks, oysters which were' taken 

 from the sea have been placed to supply the spat, and 

 these breeding oysters grow and multiply and do not 

 need to be renewed, unless they are killed by some 

 accident such as a volcanic eruption. Each pile of 



