94 DESCRIPTION OF PLAN. [CHAP. in. 



sluice, formed of fine wire, keeps out the fish that would de- 

 stroy the spawn at the time of fecundation. The spawn is 

 covered with a layer of fine round gravel, to the thickness of 

 m. 30, which the trout can easily raise as fast as it bursts 

 the egg. The snare or netting encloses the fish destined for 

 artificial breeding without hurting them, and also secures the 

 fish that are to be consumed, and those which it is necessary 

 to destroy because of their voracity, as the pike. A floodgate 

 placed at the lower end of the pond permits the pond to be 

 emptied when necessary, and an iron grating prevents the 

 escape of the fish. All the ponds are protected by a double 

 line of galvanised iron wire placed on posts armed with hooks, 

 and yet low enough to allow a boat to pass. The water of 

 the ponds finally passes into the Isere, where a permanent 

 snare allows strange fish to penetrate into the ponds. At 

 spawning time a great many trout deposit their spawn there. 

 The small pond (4) fed by the mill-stream is a sort of reservoir 

 for large fish destined for sale or domestic use. Throughout 

 the year the fish caught in the nets of the third pond are 

 placed in this basin, so when the spawning season arrives it 

 is a vast nursery for the purpose of reproduction. In the 

 house (0) built near the bridge (N) of the third pond lodge the 

 guard and the hatching-apparatus. The appareils are similar 

 to those employed at the College de France and are supplied 

 from a spring. One particular appareil, placed in a source of 

 which the temperature never varies, is slightly different from 

 the other models : it is simply zinc boxes pierced with very 

 fine holes. This apparatus, which has been in use for three 

 years, has given great satisfaction. It may be added that the 

 establishment at Buisse can supply 40,000 or 50,000 young 

 trout in the year at five centimes each, a result which is 

 mainly due to the care and solicitude with which M. de Gal- 

 bert has conducted his operations. 



What strikes us most in connection with the history of 



