PRELIMINARY CONSIDERATIONS. 5 



and the more nearly it approaches in its qualities to 

 that in which the eggs were hatched, the nearer will it 

 be to perfection as a receiving stream. 



Any little stream possessing these characters will 

 answer for rearing purposes, and it should have a 

 moderate current, not too strong for the very young 

 fishes, but not still and lifeless ripple and pool alter- 

 nating form, perhaps, the best home for fry, as they 

 can then select their own quarters. To be perfect in 

 this respect it should vary in depth from a few inches 

 to two feet, as this supplies all that is necessary for 

 the growth of trout to a considerable size. 



Next in importance to the quality of the water is 

 its quantity. This must be constant, as a stinted or 

 unequal supply, especially at the hatching-house, is 

 very injurious. Therefore, in planning an establish- 

 ment, this point should be kept well in view, so as to 

 make sure that, under no circumstances, and by no 

 accident, can the supply run short. To have to stint 

 and starve the eggs; or to think of every pint of water 

 that can be scraped and saved, adds greatly to the 

 troubles of fish culture, and detracts very much from 

 the results, as eggs hatched under unfavourable con- 

 ditions will never thrive. 



The means of supply, again, forms a matter of some 

 importance. If the water be derived from waterworks, 

 it will, of course, only be necessary to have it laid to 

 the hatching-house, and to see that the pipes are 

 sufficiently large. Hydraulic rams are expensive; but 

 if one be already on the estate, should it throw plenty 

 of water, it may be used. However, there is always 

 an uncertainty about rams, as the least thing puts 

 them out of order, and it takes some time to induce 



