88 TILE DRAINAGE. 



spade will, of course, make 16 inches of perpendicular depth. 

 Exactly horizontal, it will make no depth at all. Held at 

 u half pitch, 7 ' that is, at an angle of 4o degrees, it will make 

 about Hi inches of perpendicular depth. As ordinarily held 

 by a good ditcher, at a slight angle from a perpendicular, 

 say 20 degrees, it will make about 14 inches. If the entire 

 ditch is to be 30 inches, I usually try to make fully 7 or 8 

 with the plow, and 13 or 14 with the first spade, and that 

 leaves only 8 or 9 inches for the second, or bottoming spade. 

 The subsoil at the bottom is far more compact and hard, and 

 it is better not to have too deep a course to dig. Great care 

 should be taken to keep the grade of this course exactly 

 right, so that, when you draw the double-ended crumb- 

 cleaner and groove-cutter through the few loose crumbs of 

 clay that are always left by the spade of even an expert, 

 you will leave a true groove ready for the tiles. When the 

 ground is very wet, or the atmosphere either moist or 

 frosty, in digging and cleaning the bottom couise I always 

 keep the crumb cleaner, or "bottorner," close at hand, and 

 clean out the bottom and "true up " the groove every 6 or 

 8 feet of digging, standing at the top of the bottom course, 

 and thus never getting into the bottom of the ditch. The 

 tiles, too, if the ditch is very muddy, are laid with the tile- 

 hook shown in the hands of the first workman in Fig. L(). 

 This s-.ives one from getting very muddy. 



THE FOOT-IKON FOR DIGGING. 



One important little thing I forgot to describe among the 

 digging-tools, and that is the foot-ironsee Fig. 23. It is 

 made of plate iron or steel, about an eighth of an inch thick. 

 It is fitted to the bottom of the hollow of the boot, between 

 the heel and the ball of the foot. It is bent down behind 

 about f inch at right angles, to protect the boot-heel, and 

 bent up on a curve about an inch along each side to protect 

 the sides of the boot from wear against the handle and cor- 

 ners of the spade in digging. It is buckled over the instep 



