BULLETIN OF T1IE UNITED STATES FISH COMMISSION. 31S 



103.-EFFECT OF WASTE PRODUCTS I'lCO.'l PAGE 'S ABUnONIACAl. 



WORKS UPON YOIIVG Mil A l» FRY. 



By MARSHALL JVIcDONALD. 



[Keport to Prof. S. F. Baird for the District Commissioners.] 



I respectfully transmit herewith a report of a series of experiments 

 made in obedience to your instructions, with the object of determining 

 the extent of the injurious or deleterious influences exerted niton young 

 fish confined in water containing different proportions of the waste- 

 products from the ammonia works in West Washington. 



The sample experimented with was furnished by the Board of Health, 

 through Dr. J. H. Kidder, and was obtained from the Page ammonia 

 works in Georgetown. A portion of the original solution has been re- 

 tained for reference. The experiments were conducted by W. F. Page, 

 superintendent of propagation at the Central Station, and the result 

 shows that this waste product exerts a distinctly deleterious influence 

 when present in water to the amount of one-fourth of 1 per cent, or in 

 the proportion of 1 gallon to 400 gallons of Potomac Eiver water. No 

 experiments were made with solutions of less strength than one-fourth 

 of 1 per cent. If we consider only the direct effect on young shad which 

 have not yet begun to feed, it is probable that the area of injurious pol- 

 lution in the case of the Potomac Eiver does not extend very far from 

 the point at which the waste products are discharged into the river. 



Before coming to any definite conclusion, however, we must take into 

 consideration the fact that very young shad, which have not yet begun 

 feeding, are much less sensitive to injurious influences in the water in 

 which they are than the same fish after their sacs have been absorbed 

 and they have begun feeding. We must further consider that the 

 minute food upon which the young shad feed is much more sensitive 

 to injurious influences (especially those exerted by the presence of coal- 

 tar products) than are the young fish which feed upon them. 



RECORD OF EXPERIMENTS. 



1. — One hundred newly-hatched shad were put in 20 ounces of tin 

 refuse, 100 per cent strength, at 9.40 a. m., May 21, 1885. In 40 inin 

 utes they were all weak, at the bottom of the dish, and barely moving; 

 12 m., all dead. 



2. — One hundred newly-hatched shad were put in 20 ounces of mixt 

 ure, 75 per cent strength (3 parts refuse, 1 part Potomac water), at 

 9.40 a. m., May 21 ; 11 a. m., commenced to weaken and go to the bot- 

 tom ; 12.30 p. m., very few alive; 1.30 p. m., all dead. 



3._One hundred newly-hatched shad were put in 20 ounces of mixt- 

 ure, 50 per cent strength (10 ounces of refuse, 10 ounces of Potomac 



