45 2 FUNDAMENTALS OF AGRICULTURE. 



keep farm machines in good working order. All 

 breakages should be repaired at once, and duplicate 

 parts should be kept on hand to save delay. The 

 failure to repair farm machines promptly, often causes 

 a loss of much time and sometimes the discarding of 

 valuable machinery. 



EXERCISE. Make a list of the farm machines you are familiar with. 

 Classify them under the heads as given in this article. How much 

 more labor did it take to' raise an acre of corn in the year 1800 than 

 at the present time? What do you attribute this saving of labor to? 

 Do you know any farmers who do not keep their farm machines in 

 a sheltered place? State how these farmers lose money from year to 

 year by such practice. 



The teacher should take the class out to a large farm and examine 

 the machinery. 



SECTION LXXVI. THE DISPOSAL OF SEWAGE ON 

 THE FARM. 



By PROF. J. B. DAVIDSON, 

 Department of Agricultural Engineering, Iowa State College. 



The Requirements of Sewage Disposal. Modern 

 ideals of sanitation demand that new methods be util- 

 ized to dispose of the sewage from the farm house 

 and the outbuildings. Methods in use a few years 

 ago are not acceptable now, largely on account of the 

 installation of plumbing fixtures in the farm houses. 

 A good sewage disposal system should prevent an ac- 

 cumulation of material to harbor disease, should not 

 endanger, by contamination, the water supply, and 

 should provide for the saving of fertilizer material 

 which would otherwise be wasted. The sewage from 

 a farmstead may be emptied into a large stream of 

 flowing water if available, similar to the method pur- 

 sued by the larger river cities. It is not often, how- 

 ever, that this method can be made use of. 



The Cess-Pool. The sewage may be discharged 

 into a cess-pool, which is a reservoir with an open wall 

 through which the liquids seep away into the soil. 

 This method is the cheapest, but has little to commend 

 it. A cess-pool for average requirements can be con- 



