582 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [116] 



be 1,150 pounds, and for the month of July 35 i^er cent, l. e., 102.5 

 pounds. We desire to obtain the same increase for the period from the 

 beginning of September till the end of October — forty-five days — i. e., 

 for September 402, for October 201 ; in all, 603 pounds. Five per cent 

 of this desired increase — in round figures, 30 pounds — is obtained by 

 means of natural food, and the remainder, 573 pounds, will have to be 

 produced by artificial food. We know that 1 pound of ground meat pro- 

 duces an increase in the weight of fish of almost 1 pound. In order, there- 

 fore, to supply the required quantity of food during these forty-five days, 

 so as to make the supply equal to that of July, we need 573 pounds of 

 ground meat, which, at the rate of 15 marks [83.75] per 100 pounds, would 

 involve an outlay of 86 marks [$21,50]. By using this quantity of ground 

 meat we are able to produce 573 pounds of fish flesh, which, at the rate 

 of 50 pfennige [12 J cents] a pound, would realize the sum of 280.50 marks 

 [$71.53], leaving a net profit of 200.50 marks [$50.12.;i], from which sum 

 there should be deducted the comparatively small amount for conveying 

 the food to the pond. We are, therefore, fully convinced that the use 

 of artificial food for carp, even if there is used still more expensive food 

 than the one given in our example, will insure quite a handsome profit; 

 for although all the above calculations may not be correct in every 

 little particular, they are certainly approximately correct. 



As regards the other articles of food mentioned in the table given 

 above, those must always be considered the most profitable whose pro- 

 portion of nutritive substances comes nearest to the standard propor- 

 tion. The proper proportion can in all cases easily Jae restored by add- 

 ing a suitable quantity of food containing less nitrogen. Even in 

 employing food containing more nitrogen the pond cultivator will still 

 realize some profits, but he will find it impossible to restore the proper 

 Ijroportion of nutritive substances. Tliis, however, would hinder the 

 carp from deriving the greatest possible benefit from their food ; and, 

 with an equal (and often greater) expense, it will be found impossible 

 to obtain the same fiivorable results as with a food or mixture of differ- 

 ent articles of food which, not only as to quantity but also as to the pro- 

 portion of its nutritive substances, comes nearer to the standard pro- 

 portion. Food containing but little nitrogen, if used exclusively, will 

 always prove injurious. An example will serve to make this clear. If 

 rape-cakes are used the expense for 1,080 pounds of albumen, *. e., for 

 4,265 pounds of rape-cake, at 6 marks [$1.50] per 100 pounds, would he 

 256 marks, 8 pfennige [$04.02]. The difference in the price of this food, 

 which contains much nitrogen, will not be very great, but by the neces- 

 sary addition of some article of food containing still more nitrogen and 

 less hydrates of carbon, e.g., blood, the cost may be increased to about ! 

 300 marks [$75]. Peas, even at their lowest market price, will be too 

 expensive. The necessary quantity of albumen is contained in 5,400 , 

 l)ounds of peas, at 8 marks [$2] per 100 pounds, and this would make ! 

 the outlay 452 marks [$113] ; and, as with rape-cake, some other food i 

 would have to be added, reducing the net profits to a minimum. 



