284 American Fisheries Society 



with such gases they will soon die. It is very essential 

 that the tanks at the factories be so constructed as to re- 

 tain the residue or sludge and not allow it to enter the 

 stream. This sludge, if taken care of, makes a very valua- 

 ble fertilizer, which often more than pays for the treat- 

 ment of the sewage and gives the manufacturer a profit. 



4. Leather-hoard factory pollution. This water is taken 

 from a leather-board works. The deep red color is caused 

 by the small invisible particles of leather held in suspen- 

 sion and also by the great amount of anilin dye used in 

 the process of making leather-board. Seventy-five thou- 

 sand gallons a day of this pollution is put into the Hocking 

 River at Lancaster, Ohio. All life in the river is destroyed 

 for miles. This plant is now constructing a tank and ar- 

 ranging to use our process for the treatment of all their 

 waste liquor before permitting it to enter the stream. 



5. Creamery pollution. This sample of pollution comes 

 from a large creamery at South Charleston, Ohio. The 

 plant puts out about 100,000 gallons of waste liquor every 

 day. It is contaminated mostly by the rinsing of milk 

 cans, along with some buttermilk. This pollution, after 

 being exposed to the sunlight for one day, throws off a 

 very offensive odor. It also causes a deficiency of oxygen 

 in all water it mingles with, making it deadly to fish life. 

 You will note the action of the marl combination on it. 

 The firm has just about finished a tank to treat all the waste 

 by our process. The residue, or sludge, when utilized as a 

 fertilizer filler, is expected to more than pay for the treat- 

 ment. 



6. Sewage disposal plant pollution. This sample of 

 water, although it looks clear, is very impure. It comes 

 from one of our many sewage-disposal plants and is put into 

 the streams as pure water. You can notice that the smell 

 is very offensive. I find that odor is a very good indica- 

 tion of organic impurities in water. You will note that an 

 application of the marl combination causes a very de- 



