Trout Breeding. 27 



perhaps, on the details of the manufacture. In great 

 cities, where gas is made in large quantities, the sec- 

 ondary products of the distillation, such as tar, coal oils, 

 ammonia, etc., are saved and sold. But in small towns 

 these products are allowed to run off- in a drain, and are 

 then very deleterious to fish. The Lawrence gas-house 

 is reputed to have destroyed a shad fishery hard by, and 

 that opposite H(jlyoke is said to have driven the small 

 fish from the neighbprhood. Whereas the dock into 

 which empties the>draiavof the Boston north-end gas- 

 works, is noted as a good place to catch smelts (Os- 

 merus viridescens)." 



The Commissioners then, thirty-three years ago, be- 

 lieved in the theory that the effect of sawdust on trout is 

 mechanical, a belief which I do not share. In the re- 

 port of the Ohio Fish Commission for 1873 they say : 



"Deleterious substances prevent the increase of fishes. 

 The habit of throwing all the offal and waste material 

 from factories into the river, not only prevents the in- 

 crease, but actually destroys myriads of fishes annually. 

 The waste discharged into the river from distilleries 

 often destroys millions of fish ; the waste discharges 

 from paper mills consist of lime and other alkalies; 

 from woolen mills the waste is mostly refuse dye stuffs, 

 containing acids in various chemical combinations ; 

 from tanneries, acids, etc. The gas tar from gas estab- 

 lishments, while not absolutely poisonous, most ef- 

 fectually destroys the flavor of the fish and unfits them 

 for table use. The gas works in the city of Columbus 

 discharges the gas tar into the Scioto. What effect this 

 has up on 'scale' fish we do not know, not having heard 

 any complaint from the fishermen. During the winter 

 of 1872-73, a large quantity of cat-fish were observed 

 stranded on the 'riffles' several miles south of the city. 



