the fabric firmly against the sand wall, and when the casting was
removed, the carbonized fabric was stripped off from its face without
injury. In this way several castings have been made from one carbonized
material.

These castings are as sharp as electrotypes, whether made of soft fluid
iron or of hard, quick-setting metal. This peculiarity is owing to the
affinity between molten iron or steel and carbon. The molten metal tends
to absorb the carbon as it flows over it, thus causing the fabric to hug
the metal closely. It is somewhat analogous to the effect of pouring
mercury over zinc. You know that when mercury is poured upon a board, it
runs in a globular form, it does not "wet" the board, so to speak; but
when poured upon a plate of clean zinc, it flows like water and wets
every portion of the zinc, or, as we say, it amalgamates with the zinc.
So when molten iron is poured into an ordinary sand mould, which has
been faced with this refractorily carbonized fabric, it wets every
portion of it, tending to absorb the carbon, and doubtless would do so
if it remained fluid long enough, but as the metal cools almost
immediately, there is no appreciable destruction of the fibers.

The casting which I shall now exhibit represents a very interesting and
novel experiment. In this case, the piece of lace, having open meshes a
little larger than a pin's head, instead of being laid upon one face of
the mould, was suspended in it in such a way as to divide it into two
equal parts. Two gates or runners were provided, leading from the
"sinking head" to the bottom of the mould, one on each side of the lace
partition. The molten iron was poured into the sinking head, and flowing
equally through both runners, filled the mould to a common level. The
lace, which was held in position by having its edges embedded in the
walls of the mould, remained intact. When the casting was cold, it was