286 American Fisheries Society 



process treats it very quickly. At Cedarville, where they put out 500,000 

 gallons of water a day, they will feed this marl in at the factory and 

 let it run through the sewer to their retaining places, where it will ht 

 precipitated. In doing that, there is always a sort of scum that comes 

 on all polluted water. A bafifle-board is put across to keep it from going 

 over. This marl is fed in and allowed to run down, and it will precipi- 

 tate as soon as it slows up ; the scum is kept back and the clear water 

 will go on under the baffle-board to the next compartment. This factory 

 is going to pump its water back and use it over and over again ; they 

 are not going to let it flow into the stream. A sugar beet factory can 

 be run the same way. Unfortunately, one of the sugar beet factories 

 that I visited had adopted an inside treatment by the time I got there. 

 I made an examination of the plant and was asked to offer suggestions. 

 They applied it all right, but it was a very complicated and expensive 

 system. They let the water, after being treated, go down into a reser- 

 voir five acres in extent, and there the residue is allowed to decompose 

 and generate gases — which, of course, should not be permitted; as soon 

 as the organic matter is removed the water should be allowed to go into 

 the stream. When gases are created, the water becomes fouled again. 



Mr. Lydell: In some of these large factories they have a couple 

 of tanks through which the water is allowed to run, and while one is 

 clearing up they let the water run into the other ; then the watei- is 

 allowed to flow into the stream in a pure state. 



Mr. Travers : At most sugar beet factories and straw-board fac- 

 tories, places of this kind have already been constructed, usually some- 

 where out in the fields. 



Mr. W. E. Barber, La Crosse, Wis. : In the application of this 

 purification system, when the water stands still, all the organic matter 

 settles to the bottom. Now, if your stream is flowing all the time, the 

 water will not clear as it flows along, will it? 



Mr. Travers : Oh yes ; you do not have to stop the flow of water in 

 order to precipitate it. At one factory a waste vat has been constructed 

 to take care of 150,000 gallons a day. It is fifty feet long, six feet deep at 

 one end, and three feet deep at the other. The water comes over from 

 the factory and the clay is fed into it. The water is pumped over to the 

 vat and as it strikes the end it is slowed up, the heavier part drops down 

 first and the water flows to the other end. It has to go under the 

 baffle-boards, and the water that goes in first must be the first out; and 

 when it gets over to the sewer it is as clear as crystal. 



Mr. Barber: The sanitary engineer connected with our Wisconsin 

 Board of Health recommends a filtration plant constructed of coke. 

 They are going to compel manufacturing plants, turning out paper, sul- 

 phite, etc., to install that kind of arrangement. 



Mr. Travers : It will probably break some of them to do so, because 

 it is a very expensive outfit. I recently visited a disposal plant at 

 Canton, Ohio, which is constructed along that line. They have 16 

 coke filtering beds, each half an acre in extent. The city of Canton is 



