818 EEPOET OF COMMISSIONER OF FISH AND FISHERIES. 



these examinations affords us tlie data not only for a daily summary of 

 the breeding stock of either sex on hand, but also for some generaliza- 

 tions on the movements of the fish as affected by the weather and other 

 phenomena. 



The main pound, where the most of the fish were kept, was, as before, 

 very commodious — about 70 feet long and 40 wide, with a maximum 

 depth of about 5 feet. In this many hundred salmon lay quietly together, 

 making, so far as we could observe, no very strenuous exertions to es- 

 cape, except a few cases. Another pound of equal size was provided 

 for the spawned fish to lie in while awaiting their transfer to the lake. 

 Besides these, the two trap-pounds, and the "main lead," five other 

 enclosures were provided to enable us to properly assort the fish as we 

 were using them ; for instance, in one would be placed those that were tried 

 and found unripe ; in another those that had yielded their eggs and 

 were waiting to be pressed the second time, which was always done ; 

 another would contain surplus males ; another, fish notable for any pecul- 

 iarity which it was desired to observe further. All these enclosm^es were 

 formed of fine-meshed nets hung on stakes and for the most part held 

 down at the bottom by the weight of chains, which rendered it easy to 

 transfer a whole body of fish from one enclosure to another by lifting 

 the bottom of the net and driving them under. 



The only change made at the hatching-house was the complete clean- 

 ing out of the brook which afforded an outlet both for the water of the 

 spring and the surface water of the vicinity. This flows for a long dis- 

 tance over flat, low ground, and on two former occasions sudden rains 

 had raised the water until it reached the tops of our hatcliing-troughs, 

 threatening, but not accomplishing, serious mischief. To avoid a disas- 

 ter from this source the brook was cleared out, widened, and deepened 

 for a distance of about 140 rods. Even with this improvement, how- 

 ever, the site of the hatching-house is a very unfavorable one. Both 

 spring and brook water can be used, but the brook is a tiny one, and in 

 cold and dry weather shrinks to a very insignificant volume, while the 

 spring issues from the ground at such a slight elevation above the swamp 

 through which it flows that at best we can barely get our troughs high 

 enough to avoid flooding by freshets. There is thus no opportunity of 

 iaerating the water by a fall, and the trough must be placed on a level 

 with the floor, an unfavorable position for work. However, no better 

 arrangement could be made. No larger spring could be found in the 

 neighborhood ; there was no clean and ample brook j and the water of 

 Grand Lake Stream itself, though probably unsurpassed for such a pur- 

 pos^e by any in the world, could not be used on account of certain phys- 

 ical difi&culties w^hich I saw no way of surmounting with the means at 

 my disposal. 



2. — The fishing. 



The main nets were placed in the stream September 17, and at the 

 same time a strong movable net iDlaced across the head of the canal 



