PRACTICAL NOTES ON UNDERDRAINING. 593 
line at the outlet of the drain is represented by the dotted lineog. To commence 
properly, drive a stake three feet high at h and one at *, where the ditch is to be cut ; 
then drive another at i, so that the Fie. 16 
tops of each will be in an exact line sa Site 
as represented by the dotted line be- 
neath, hik. The stakes at h and i 
must be just far enough apart to sup- 
port the two legs of the level, (Fig. 
13.) After the stakes, h i, are driven, 
place the level on the top of them, 
and make a mark on the cross gradu- 
ated bar at the point where the f 
plumb-line settles while the rfile is 
on the tops of the stakes; the ditcher 
will then have a cheap and reliable 
rule to enable him to grade the bot- 
tom of the ditch with the most desirable accuracy, at any point from atob. Let him com- 
mence at a and sink the ditch as deep as the outlet can be dug; set the level in the bottom 
frequently until the correct inclination is secured; then, if there should be any danger 
that either bank will cave in, let the tiles, planks, or stones be put in the bottom and 
covered with dirt at once, when the digger can proceed to excavate another lineal 
rod, and grade the bottom with as much accuracy as it could be done were all the 
ditch excavated before any portion of it is stoned or tiled. 
Different styles of ditching-plows.—By employing strong teams and plows of proper 
construction, a vast amount of manual labor may be avoided. A steel mold-board plow 
with a sub-soil attachment is employed in many States both for ditching and pulver- 
izing the soil, where the substratum needs to be broken up. In many instances it 
becomes necessary to put the weight of a man on the beam in order to make the plow 
enter the hard ground. A strong piece of plank is bolted to the underside of the beam, 
on which aman can stand. The plank also serves to prevent the plow from plunging 
down too deep in a soft place. By having a spar of wood bolted erect to the side of 
the beam, a person can ride a plow-beam without danger and with little fatigue. 
Where there are but few stones to obstruct a plow, a ditch can be sunk rapidly with 
such an implement. 
Fig. 17. 
Figure 17 represents the Iowa deep-trench plow, which is so constructed that the 
entire furrow slice rises and slides up the inclined mold-board almost as high as the 
lower side of the beam before it is turned over. By driving twice or thrice in a furrow 
where it is desirable to make a ditch, if the substratum is not too stubborn and strong, 
such a piow will open a ditch thirty inches deep, which will only require a small 
amount of manual labor to grade the bottom for a course of tiles. 
These plows are very large, strong, and heavy, weighing three or four hundred 
pounds. Three or four yokes of strong, heavy oxen are required to draw one satisfac- 
torily. No part can be broken by any tair means. <A gauge-wheel should be employed 
beneath the beam until the implement is required to enter its full depth, when the 
wheel may be removed and the plank-shoe substituted. Where there are many large 
boulders, or much hard-pan, such a plow would require more teams than could be made 
to draw advantageously in a line withont much previous training. 
The subsoil plow proper, (Fig. 18,) is employed extensively, in sinking deep ditches, 
simply to turn up and pulverize the hard substratum in the bottom of a ditch, so that 
the earth may be thrown out with shovels. The standard consists of a plate of cast- 
iron nearly one inch thick, of the form shown by the cut. The share or point is made 
strong, so that it cannot be easily broken. The light-colored portion above the share 
38 A 
