138
AGRICULTURE ON THE RHINE.
Fig. 2 is a narrow spade bent at the angle, shown in
Fig. 2, B, to the handle. With this the grass is cut
under the roots when sods are to be raised, and it serves
to transport the soil or rubbish, as may be required, from
one spot to another. TLe bottoms of the canals are
levelled with this instrument.
Fig. 3 is a board nailed at right angles to a pole, and
is used in levelling the surface and the bottoms of the
canals. Three of these sight-boards are requisite.
Fig. 5 is a tube of tin, the ends of which are raised at
right angles. At the top of these raised ends continua-
tion tubes of glass are affixed, that allow the play of the
water, with which the tube is filled, to be seen. The
contrivance is intended to save expense in the glass, of
which material the whole tube may be made. When
fixed upon a pole by means of the socket this instrument
shows the level of the surface.
Fig. 4 is a common plumb on a long board. It is
used for ascertaining the level at short distances.
Thepropertime for cleaning out the ditches and canals
is late in the autumn, when the cattle are no longer driven
to the meadows. A day is fixed by the overseer of the
meadows by which all the canals have to be cleaned out
under a certain penalty. Then it is that the principal
watering for the year takes place. If there has been
heavy rain and the irrigating brooks are muddy, the water
is not let on to the meadows until it begins to get clear.
Too great a sediment fills up the canals and leaves un-
equal deposits on the surface that mar the labours of the
meadow-owner. In the autumn no fear is entertained of the
meadows being overwatered. The great point sought to
Agkicultuke on the rhine,
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