DAIRY AND SEED IMPROVEMENT MEETINGS. 21/ 



although the double wall with the air space is still better. But 

 there is a vast difference between putting a tank of that kind 

 inside a hollow walled building and putting it inside a building 

 like the one described in the paper. The ice would melt very 

 much faster in the latter than in the double walled concrete. 



Ques. I would like to ask about the septic tank. 



Ans. I will be very glad to tell you more about the septic 

 tank. It depends for its success practically upon just one thing, 

 and that is the exclusion of a circulation of air ; because the 

 bacteria that destroy sewage, the anaerobic bacteria, while they 

 can multiply in the presence of plenty of oxygen still their 

 deadly enemy, the putrefiers, multiply so much faster that it 

 would be like attempting to start a rat farm and a cat farm 

 together, — it would not succeed. The whole method of dis- 

 posing of sewage by a septic tank is to allow your friends, the 

 anaerobes, to multiply and destroy the organic matter. They do 

 not destroy the mineral matter, but there is very little mineral 

 matter going into a septic tank. It is just as good for the farm 

 home as for the dairy. The first question that always comes 

 up is. How often does it have to be cleaned? About once in 

 360 years. If you are so tender of the feelings of your chil- 

 dren's cliildren's children's children, that you do not want them 

 to have to do that, do not install the septic tank. 



Another question that very frequently comes up is, What is 

 the best disinfectant? If you should put a disinfectant in you 

 would kill your friends, the anaerobes. You do not want to put 

 in any disinfectant. An ordinary disinfectant used on the farm 

 may be allowed to run into the tank because it would be so 

 diluted that it would not have much eft'ect on the bacteria. 



Another question is. Does it freeze in the winter? It does not 

 freeze in the winter for the reason that all of the fluids that 

 go into it are so much warmer than the freezing point, and bac- 

 terial action creates heat. It has been used nine inches under 

 ground in places where the thermometer went to 45 below zero 

 without freezing, and a thing that has always been surprising 

 to me is that the outlet pipe, the bottom of which is only 12 

 inches under ground, does not freeze. Even that has never 

 made any trouble to my knowledge. 



As to the method of installation, for a family of six the size 

 should be six feet long, three feet deep and three feet wide. 



