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disagreeable job. The plan which Mr. Ainsworth has in- 

 vented obviates, in a great degree, these objections. As 

 his apparatus is not patented, but generously offered free 

 to the public, we describe it here. The difficulty in getting 

 eggs impregnated naturally has been that the Trout would 

 eat so many of them, when laid, and that being scattered 

 about, on and under the stones and gravel, they could 

 not easily be collected, and many, in any event, would be 

 lost. The problem which Mr. Ainsworth had to solve was, 

 then, to keep the Trout from eating the eggs after they were 

 laid, and to devise a plan by which they could be easily 

 collected. This he accomplished by laying in the raceway 

 two wire screens. The lower one of such fine wire that 

 the eggs will not pass through ; that is, of about ten or 

 fourteen threads to the inch. This wire is attached to a 

 frame, made of inch stuif, and another inch strip nailed 

 above it. Another frame is provided, of the same width 

 and length, but the sides of which are from three to five 

 inches deep ; upon this a coarse screen, of three or four 

 wires to the inch, is fastened. The fine screen is first laid 

 in the race, which being made of proper width, it fills, and 

 the coarse screen is laid over it, with the wire side down. 

 And there is a space, between the two screens, of one inch, 

 protected from invasion on the top and bottom by the wire 

 screens, and on the sides by the inch strip, on every side 

 of the small screen. The top screen, which has sides three 

 or four inches deep, is then to be filled with coarse gravel 

 (so coarse that it will not pass through the meshes), to the 

 depth of two inches. This gravel will overcome the buoy- 

 ancy of the wooden frames, and cause them to sink into 

 the water. Now the screens are ready for use. Let us see 

 how they operate. A Trout comes along, and finds the 

 gravel. She sees no screens — only some nice gravel for 

 nest-building, in what appears to be a shallow box. Sus- 

 pecting no evil, she proceeds to make her nest, and in the 



