soda base, obtained by melting 2 parts sand with 3 parts of carbonate of
soda). As the colors applied do not stand the action of the brush, the
soluble glass is projected against the wall by means of a spray. After a
few days the walls should be washed with alcohol to remove the dust and
alkali liberated.

The colors used for this style of painting are zinc white, green oxide
of chrome, cobalt green, chromate of lead, colcothar, ochers, and
ultramarine.

Soluble glass has also been used in the manufacture of soaps made with
palm and cocoanut oil; this body renders them more alkaline and harder.

Interesting experiments have been made with soluble glass for coloring
corals and shells. By plunging silicated shells into hot solutions of
salts of chrome, nickel, cobalt, or copper, beautiful dyes in yellow,
green, and blue are produced. Here seems to be a field for further
application of this discovery.

Soluble glass has also been applied to painting on glass in imitation of
glass staining. By using sulphate of baryta, ultramarine, oxide of
chrome, etc., mixed with silicate of potash, fast colors are obtained
similar to the semi-transparent colors of painted windows. By this means
a variety of cheap painted glass may be made. Should these colors be
fired in a furnace, enameled surfaces would be produced. As a substitute
for albumen for fixing colors in calico printing, soluble glass has been
used with a certain degree of success; also as a sizing for thread
previous to weaving textile fabrics. Thus it would seem that this
substance has been used for many purposes, but since its application does
not seem to have been extended to any great degree, the defects here