Marsh. — Sewage and Fish Culture 175 



and clean water admitted to the ponds, the quantity 

 and distribution of the higher plants, which afford pro- 

 tection and attachment for many animals, and lurking 

 places for yong fishes, the adaptation of the stock of 

 fishes to the capacity of the pond, these are prime ele- 

 ments in the even driving of the process. They require 

 constant supervision and regulation. Moreover the 

 method as a whole, while it has been made workable by 

 repeated modification through a long series of experi- 

 ments, will be further perfected by the experience gained 

 from continued use. 



As is not difficult to infer, the introduction of fish 

 from the sewage ponds to the market as table fish did 

 not fail to encounter the opposition of natural prejudice, 

 even in Germany where the carp, the principal species 

 produced by this method, is in high favor and where the 

 public is highly amenable to reason. It required an 

 organized campaign of education by means of lectures 

 and various authoritative propaganda. It was explained 

 that the carp in its natural habitat sought the vicinity 

 of whatever sewers were available, finding there its 

 food most abundant ; that the public had long been eating 

 carp bred under similar and less well controlled condi- 

 tions; that there was no offense in or about the sewage 

 fish ponds, as anyone might see by inspecting them ; that 

 there was no logical or hygienic objection to the use as 

 food of fish grown in them ; and finally by serving them 

 to a representative public, directly from the ponds, 

 these fish were shown to compete in attractiveness with 

 any other. The whole product of the ponds is disposed 

 of without difficulty in Strassburg. The fish are taken 

 alive in tanks of water to the city and the consumer 

 may make his choice of an obviously fresh specimen, a 

 fact which no doubt facilitates the sale. The income 

 from the sale of the total products of the disposal plant 

 suffice, according to the management, to pay all the ex- 

 penses of the process and leave a small margin of profit. 

 Exact figures are not available, but the attainment of 

 an even break between profit and loss has doubtless been 

 the goal sought and one hitherto entirely beyond reach. 



