more than enough to fill the scraper can be shoved forward. It is made in two and four-horse sizes, and should be rapidly introduced.

The wheel scraper is an improved form of the scraper mounted on wheels, and is adapted to work where the earth must be drawn longer distances than will warrant the economical use of the slush or the Fresno scraper. The common field plow and the heavy road grading plow are sometimes used in opening out the first portion of small drains and loosening the earth in large ditches

Figure 113. Outlet which of necessity opens under the surface of a stream or pond, thus endangering the tiles from splitting by freezing, when filled with water. A few rods of the drain next to the outlet might better be made of oak boards nailed together so as to form a square box.

where other machinery or even spades are used to take up the loosened earth.

The reversible road machine has come to be recognized as a very important implement in making open drains. With this machine, broad, flat drains can be made which will carry large volumes of water and which can easily be cleaned out by using the same machine. In many cases crops can be grown over the banks and within the broad flat ditches, thus making the drain useful for removing the flood water without seriously injuring the area useful for the common crops of the field. In other cases, these broad, flat drains may be sown to permanent grass and mowed two or more times annually. This insures a ditch free from debris and

often crops of valuable forage. Since the use of road machines is described more in detail under the heading of road making, a discussion of their operation will not be necessary here. In Figure 118 is shown the crosssection of a ditch made with a reversible road machine where it is desirable to have the ditch next to a fence with one side not rounded so as to be crossed with teams and implements. The side next to the fence can be left nearly vertical, as at A; it can be made slanting, as shown by the dotted line, B; or, if it is desired even thus close to the fence, it can be made rounded as at the dotted line, C. The earth taken from the ditch can be left in a sharp ridge, as at D; can be thrown up into a rounded form, as at F; or can even be smoothed down by

Figure 114. General plan of a si1t well, two branch tiles entering and main discharging. The silt accumulating at O by settling in the nearly quiet water should be cleaned out as required, lifting the stone, X, for that purpose.

carrying it back on the adjacent land, as at E. This class of machine is not adapted to making very heavy ditches, though, in many cases, the upper portion of the ditch may be opened by means of the road machine.

Figure 115. Drag or slush scraper.

The elevating grader is very useful in opening large drainage canals. This machine does heavy work at a comparatively low cost per cubic yard of earth handled.

Ditching plow.-A very strongly constructed plow

made to resemble somewhat the common stubble plow and very useful in drainage operations. Either this or the common plow is often used to break up the soil before carrying it to one side with the reversible machine, or

picking it up with the wheel or slush scraper, or throwing it into wagons with the shovel or spade.

Vertical and special drains.-While most farm drainage can be accomplished by means of either open drains or

tile drains, there are other forms of drains which are useful for special conditions. Drainage wells are useful where vertical drains can be made cheaply through impervious layers of clay or stone which hold the water

Figure 118. Showing forms of ditch beside a

fence line, as at the side of a public highway.

A-D, ditch made with steep bank and dirt left in

in the saucer-shaped area, thus carrying the water downward into the nonwater-bearing stratum of gravel or sand below. In Figure 131 the hills surrounding the low area are so high that a horizontal

high ridge. B-F, ditch made with slanting outer drain under the ad

bank and ridge rounded down. C-E, ditch

rounded and earth spread out so that land can be joining hill would be

mowed or even cultivated to the roadway, as at P.

very expensive. A well is sunk at one side, or if a dry time can be found when the low area is dry, the well can be sunk in the midst of the wet area. Drain tiles, laid from 1 to 3 feet under

neath the surface, receive the water, thoroughly filtered and clear of sediment, and carry it to the drainage well by which it is carried through the impervious layer and

enters the loose gravel or sand layer below. If the water were allowed to run from the surface into the drainage well, so much debris would be carried in that the well would soon become clogged and water would

Figure 120. Floating dredge. the ditch in front of the boat. earth on the bank of the canal.

Longitudinal view showing scoop taking earth out of
Cross-section showing scoop in position to deposit

no longer sink freely through it. However, in some instances, where the impervious layer is near the surface and is not thick, drainage wells may be left open