s per rod, (if the
scraper, Fig. 39, can be successfully used for the rough filling, the cost
will be reduced considerably below this.)

The four items of the cost of making one rod of lateral drain are as
follows:

Digging the ditches - - - .43
Grading - - - .06
Tiles and laying - - - .21
Covering and filling - - - .10
- - -.80 cts.

If the drains are placed at intervals of 40 feet, there are required 64
rods to the acre,--this at 80 cents per rod will make the cost per
acre,--for the above items,--$51.20.

How much should be allowed for main drains, outlets, and silt-basins, it
is impossible to say, as, on irregular ground, no two fields will require
the same amount of this sort of work. On very even land, where the whole
surface, for hundreds of acres, slopes gradually in one or two directions,
the outlay for mains need not be more than two per cent. of the cost of
the laterals. This would allow laterals of a uniform length of 800 feet to
discharge into the main line, at intervals of 40 feet, if we do not
consider the trifling extra cost of the larger tiles. On less regular
ground, the cost of mains will often be considerably more than two per
cent. of the cost of the laterals; but in some instances the increase of
main lines will be fully compensated for by the reduction in the length of
the laterals, which, owing to rocks, hills too steep to need drains at
regular intervals, and porous, (gravelly,) streaks in the land, cannot be
profitably made to occupy the whole area so thoroughly.(22)

Probably 7-1/2 per cent. of the cost of the laterals for mains, outlets,
and silt-basins will be a fair average allowance.

This will bring the total cost of the work to about $60 per acre, made up
as follows:

Cost of the finished drains per acre - - - $51.20

7-1/2 per cent. added for mains, etc. - - - 3.83

Engineering and Superintendence - - - 5.00

Of course this is an arbitrary calculation, an estimate without a single
ascertained fact to go upon,--but it is as close as it can be made to what
would probably be the cost of the best work, on average ground, at the
present high prices of labor and material. Five years ago the same work
could have been done for from $40 to $45 per acre, and it will be again
cheaper when wages fall, and when a greater demand for draining tiles
shall have caused more competition in their manufacture. With a large
general demand, such as has exi