CHAPTER X 



USING THE HOSE-LEVEL WITHOUT LEVELING 



RODS 



FOK drains of moderate length, when the surface of the 

 land is fairly regular, and when the fall does not exceed 

 three feet for the whole line, a very simple procedure may 

 be followed. Figure 75 represents the profile of a piece of 

 field in which a 400-foot lateral is to be laid. The lateral 

 must be 40 inches (3 feet 4 inches) deep at the main. The 

 grade stakes are in place (50 feet apart) as shown in the 

 figure. Stake 1 was a grade stake of the main and the 

 depth of the main at that stake has determined the depth 

 of the lateral at that point. 



235. Long stakes. Two inches back from each grade 

 stake, there must be driven firmly into the ground one of 

 the stakes that will later be needed to carry the grade bar 

 (or " batter board " as it is sometimes called). This 

 stake should be 1 X 4 inches, and after driving, should 

 stand out of the ground 3 to 5 or more feet, depending 

 upon its location in the line and the fall of the land and 

 of the drain. Each stake must be as high as the level 

 of the grade bar at the head of the drain will stand. When 

 in place, it should be perpendicular and its face should 

 stand at right angles to the line of the drain. These 

 stakes are shown in Fig. 76. 



236. To establish datum plane. The depth of the 

 drain at its upper end should now be determined. That 



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