TWELFTH ANNUAL REPORT. 99 



counties. They contain no living thing — neither fish, frog, cray- 

 fish, nor any form of animal or plant life. 



The coal and coke industries which have brought about these 

 conditions may possibly be regulated at some future time. At 

 present their vast importance and the state of public opinion do 

 not give us any hope for stream purification in coal mining 

 regions. 



The well-known conditions of pollution extending throughout 

 the Hudson River and its tributaries may be found in all rivers of 

 the country where the population is great and the manufacturing 

 industries well developed. 



Boards of health throughout the country are considering the 

 conditions, but little is accomplished except where local condi- 

 tions here and there become intolerable. Officers are usually 

 unable to enforce existing laws and juries will not convict. 



The Herculean labor involved in setting things right will re- 

 quire the consent of the population and a liberal use of the money 

 and efifort of the present generation, wdiile the next generation 

 will need to be vigilant in sustaining whatever protection may be 

 secured. 



In Europe many of the problems connected with sewage dis- 

 posal have been solved, and considerable help is thus available 

 from the experience and practical efiforts of other countries. 



It is not the object of the present article to discuss the condi- 

 tions which prevail in such rivers as our own Hudson ; the large 

 navigable rivers, flowing through densely populated sections, will 

 have to be dealt with from the viewpoint of public health. Anglers 

 as a class are, however, interested in the upper waters of our 

 streams, where they go for recreation, and the protection of such 

 waters is quite possible. 



Many years of experience in the field as an officer of the United 

 States Fisheries Bureau has led me to the belief that there is 

 hope for the early salvation of our mountain streams where the 

 population is not yet sufficient to cause damage by sewage. Here 

 we have to deal chiefly with such matters as pollution by saw- 

 dust and wood pulp refuse. 



Sawdust not only blackens the water, but drifts into eddies, 

 where it becomes water-logged and settles, forming deposits 

 which are very destructive to young fishes. It also settles into 

 the gravel beds, and to some extent covers them, making unsafe 

 for fish eggs many important spawning grounds. 



Recent experiments by the National Fisheries Bureau have 

 shown that sawdust promotes the growth of fungus on fish eggs 



