SALMONOIDS AND TURBINES. 255 



As the larger Trout (six in number) had again been lost in the 

 stream by careless fastening of their box, only small Trout of the 

 same size as previously were available. Fifty of these small 

 Trout were pushed through the wooden tube, as before, at 

 4.36 p.m. The turbine was kept in action for half an hour. 

 No fish occurred in the net, showing that the Trout had either 

 lurked in the tail-race or had escaped by chinks. Fragments of 

 lacerated forms would in all probability have been carried against 

 the net by the currents. In the turbine-pit a single example 

 was secured, but others were observed escaping by the iron 

 shoots. These had refused to be carried down the shoots during 

 the action of the turbine. A single large Trout appeared behind 

 the wire guards as the man entered. It had either lurked in the 

 pit after the previous experiment, or found an aperture large 

 enough for entrance, though the latter is unlikely. It could 

 scarcely have passed up the iron shoot. 



(XIV.) In this case the Alcott turbine was employed. At 

 5.46 p.m. fifty small and two larger Trout were pushed as before 

 down the long wooden tube into the iron shoot. The eddies in 

 the tail-race, as previously, pushed the upper part of the net 

 inward, and thus it was less fitted for service. The turbine was 

 in action for half an hour, and was then stopped. On raising 

 the net a portion (4 in.) of the posterior end of a large Trout was 

 found. Such evidently had been lacerated in the turbine. No 

 evidence of the smaller Trout was obtained. 



(XV.) Both turbines (Alcott and Hercules) were put in action 

 at 6.30 p.m., and, the wooden tube having been removed, fifty- 

 two small Trout, two Perch, and one larger Trout were placed in 

 the general cavity of the pit, which had both butterfly valves 

 open. The fishes thus had perfect freedom in the large cavity 

 formerly indicated. The current rushing out at the tail-race 

 floated the bag of the net more satisfactorily than when either 

 turbine was worked singly. The turbines were stopped in 

 twenty-five minutes, as darkness was coming on. Only a single 

 Perch, devoid of its head and with the body split, was in the net. 

 Two small Trout were caught in the turbine-pit, whilst three or 

 four escaped over the edges of the iron shoots as the water 

 drained off. As before, these and probably others declined to be 

 drawn into the vortex over the shoots. In the ordinary working 



