The very latest Methods. 



397 



SECTION SECOND. 



AINSWOETH'S EACB AND SCREENS. , 



A. Top of Race. B. Water Level. C. Upper Screeu, or Sieve. D. TJuder Screen. E. 

 Bottom of Race. Q. Supply Pond. H. Filtering Gate. 



The Upper Screen is represented from the gronnd-plan, in order to show the form of 

 the perforated bottom, and the same after paving it with pebbles. The bottom of 

 the Race is also represented from the same view ; but the side only of the Under 

 Screen is represented. The whole is suggestive, calling for judgment and science 

 in construction. 



The object of this invention is to induce trout to spawn where 

 the fish-culturist may gather the eggs and protect them 

 until he can transfer them to the hatching-boxes once or 

 twice a week, and it is a valuable step on the road of aqua- 

 culture toward husbanding all the resources of a stream. 

 The object is to form a race-way of water in a stream of 

 moderate flow, and divide this race into three compart- 

 ments. Those are the bottom of the race paved with cob- 

 ble-stones, E ; a few inches above it, and of the same width, 

 is the lower screen or sieve, D ; a few inches above which 

 is the upper screen, C. Trout have access to screen C for 

 spawning, and as the bottom of it is perforated with holes 

 twice as large as a trout's egg, of course the eggs laid on 

 it will run through the bottom of the screen and lodge on 

 the under one, which is perforated with very small holes 

 to drain it, but not pass the eggs. Screen C is divided into 

 trays, with handles at the sides for removing them by the 

 hand; the bottom is then covered with pebbles, as indi- 



