Iron County register. [volume] (Ironton, Iron County, Mo.) 1867-1965, 1889-11-14
SPAN LEVEL.

OF the crOSS-plece d e screw a common
rs cent spirit level G, SO that when
b stands on level floor the air
bubble shall show level, and its middle
be the middle of d e. Change the tri-
angle end for end on the floor
to be sure your spirit level is ex-
actly parallel with the bottom of c..
Then if you want to graduate it raise
b A-inch at a time, leaving C resting
on the floor, and mark the brass of the
spirit level for each quarter and half
inch up to two or three inches. Then
raise in the same way and graduate
the other side. Before the groove is
cut in the bottom of the ditch this span
level may be applied all along, and
show the exact fall per rod. Then the
groove cutter can take out humps, and
the level test its work. b is half
rod long, and so 4-inch fall for it's
length makes 15-inch fall per rod, and
so on. Never be content unless your
level shows some fall towards your
outlet.
The more uniform the fall the better.
If you know for example that your whole
fall is only one-half inch per rod, you
must keep your grade down to about
that rate, not varying, or you will have
trouble. Beginning at the lower end
the tendency of a new hand is to close
grade" that is, work towards the sur
face. The span level will help prevent
this. Instead of the spirit level
plumb bob may be hung by line from
it (see figure), SO that when b is level
the line shall come opposite the middle
of d e. Its scale may be graduated and
marked as in the case of the spirit
level.
How TO LAY THE TILEs.-The groove
should be cut so that the tiles will fit
without rolling, and shall touch bottom
all the way. Different sized scoops
should be used for different sized tiles.
Lay the tiles from the outlet up stream,
look through each tile to see that it is
clear of instructions, and lay it so that
it will not rock or wabble, i. e., curved
up, and not down in the middle, if curved
at all. Chuck it up tight against the
preceding tile, and then step forward
upon it and lay the next. I prefer to
stand in the ditch, lay each tile by hand,
and stand on it to press it firmly to its
place. Assert the tiles in scattering
them along the ditch so that the harder
burned (smaller) ones shall come to-
gether, and not be mixed in among the
softer-burned ones. But lay none that
are not hard burned enough to give a
clear, metallic ring when struck with
hammer, and lay no cracked or broken
ones. For functions with laterals get
from the kiln, if possible, main tiles
with functions formed, or at least holes
cut for functions. If you have to cut
with trowe1, use great care and secure
great perfection.
How TO COVER THE TILEs.-First,
stand in the ditch when the tiles are
laid, and with the ditching-spade shovel
in the fine clay (the subsoil last dug
QUIT, and see that it rattles or fills clear
down on both sides of the tiles. Tramp
very thoroughly with the feet as you
fill, until you have filled in some eight
inches deep. The rest may be plowed
in by running very long eyener and
long inside lines. and having one horse
on each side of the ditch. If possible,
the field drained in the fall should have
been tiled in hoed crops all summer.
The soil and subsoil are more moist
early in the fall, and dig far more easily
than when in turf, or even in wheat or
oats. Still further, the filling by team
is far easier, and the blowing of the
field for the next crop will efface all
signs of the ditch.