SALMONOIDS AND TURBINES. 249 



at 3.1 p.m. In a few minutes a number of the Trout appeared 

 in the tail-race, and they continued to drop down at intervals. 

 Shortly after commencing, however, the right pole of the net in 

 the tail-race gave way, but in a few minutes (five) it was put in 

 position and fixed. In half an hour the net in the tail-race was 

 lifted, and a dead fish dropped from it, whilst a few escaped from 

 the pocket. Only one of those put in was secured, though two 

 Parr, considerably larger in size, were captured, but these may 

 have come only from the tail-race. Many of the young Trout 

 of the series placed in the pit were observed at the right wall of 

 the tail-race above the net, but though Mr. Armitstead carefully 

 fished, after stopping the turbine, the tail-race above the bridge 

 to which the net had been fixed, he caught none. They were 

 too nimble in the dark water. 



The turbine-pit was in this instance emptied by a great rush 

 outward, and unfortunately every Trout was swept out with the 

 current. No dead or mangled fish was observed in any part of 

 the apparatus, with the exception of that already mentioned. 



(VI.) The sixth experiment took place at Mr. Webb's Mills, 

 Eandalstown, Co. Antrim, on September 26th, 1900, with one of 

 a pair of turbines situated in a large chamber (pit), into which 

 the water had a fall of 12 ft., entering from a wide sluice-gate 

 through iron bars. By the inexperience of the men to whom 

 Mr. Armitstead had committed the charge of the Trout (for he 

 had missed the night-train), the box — containing two hundred 

 and fifty Trout 4-6 in. in length — was carried under the gates, 

 and all escaped except twenty-two. At 12.48 p.m. the twenty- 

 two Trout were placed in a box having a bottom of perforated 

 zinc, with various holes in the sides and lid, and with long 

 stays or struts reaching to the platform, where they were 

 held. The lid was hinged, and could be lifted by a cord, so 

 that the Trout on escape were within the powerful currents 

 entering the apertures of the turbine. The fishes were thus 

 brought close to the apertures of a 33-in. Achilles turbine, 

 having one hundred and twenty-five revolutions in a minute. 

 During the first few minutes of the experiment, indeed, the 

 revolutions were three hundred per minute. As the machinery 

 was used solely for electric light, a steady rate was necessary. 

 The tail-race led into a broad open pit, from which the water 



