rails, _e_, and parallel with them, are fixed two strong screws, _e'_,
held by supports that raise them to the bottom of the car frame, so
that they can be affixed thereto. When once the car is fastened in
this way, the screws are revolved by means of winches, and the block
is thus made to advance or recede a sufficient distance to make the
lines marked on its surface come exactly opposite the saw blade.

In sawing hard stones, it is necessary, as well known, to keep up a
flow of water and fine sand upon the blade in order to increase its
friction. Upon two platforms, _b_, at the extremities of the machine,
are fixed the water reservoir, C, and the receptacles, C', containing
fine sand or dry pulverized grit stone. As may be seen from Figs. 5
and 6, the bottom of the sand box, C', is conical and terminates in a
hopper, T, beneath which is adjusted a slide valve, _t_, connected
with a screw that carries a pulley, T'. By means of this valve, the
bottom of the hopper may be opened or closed in such a way as to
regulate the flow of the sand at will by acting upon the pulley, T',
through a chain, _t'_, passing over the guide pulley, _t²_. A rubber
tube, _u_, which starts from the hopper, runs into a metal pipe, U,
that descends to the guide, H, with which it is connected by a collar.
Under the latter, this pipe terminates in a sphere containing a small
aperture to allow the sand to escape upon an inclined board provided
with a flange. At the same time, through the rubber tube, _c_, coming
from the reservoir, C, a stream of water is directed upon the board in
order to wet the sand.

As the apparatus with but a single endless saw makes but two kerfs at
once, Mr. Auguste has devised an arrangement by means of which several
blades may be used, and the work thus be expedited.