Tr avers. — Fighting Pollution in Ohio 283 



pumped out, it decomposes the iron pyrite and sulphur, 

 forming- ferrous sulphate. This combination, going out 

 into a stream, will consume all the oxygen in the water, 

 killing off all fish life. Five minutes after treatment by this 

 process, fish will live in the water so treated. 



2. Steel mill pollution. An acid solution is put out by 

 steel mills. Where pickling vats are used, the mills dump 

 into our streams from three to ten thousand gallons a day 

 of from 1 to 4 per cent solution of sulphuric acid. It is 

 very deadly to fish life. An application of this marl com- 

 bination neutralizes the acid in a very short time. The 

 amount necessary to apply is very small, depending on the 

 acid strength of the solution. 



3. Canning factory pollution. We have an organic pol- 

 lution put out by a canning factory, of which there are a 

 number in our state. Pollution of this kind is very deadly 

 to fish life on account of the very fine particles of corn and 

 peas held in suspension in the waste as it leaves the factory. 

 This water is very impure, but about 100 grains of the 

 marl combination to 1 gallon will make the water clear as 

 crystal. This pollution is very offensive and is the cause 

 of considerable complaint. All organic pollutions are 

 handled in the same manner. The marl is applied by means 

 of an automatic dry feed machine in a tank of large 

 enough capacity to slow down the waste liquor as it issues 

 from the factory. The solids in the water drop to the 

 bottom of the tank, and the clear water, free from pollu- 

 tion, flows into the stream. I find that not all organic 

 pollutions, when they first flow out of a plant, are neces- 

 sarily fatal to fish life. However, after they are out in the 

 stream forty-eight hours or so a very decided change takes 

 place. In the process of nature, foreign matter held in 

 suspension will first precipitate to the bottom of the stream, 

 where it will soon commence to ferment and generate poi- 

 sonous gases which rise through the water, causing a de- 

 ficiency of oxygen. Where fish get into water charged 



