Frostburg mining journal. [volume] (Frostburg, Md.) 1871-1913, 1897-07-31
SUBSTITUTES FOR GLASS.
Three Compositions Coming Into Use In
Europe.

Three Compositions Coming Into Use In
Europe.
There are several substitutes for glass
in use in Germany, the chief among
them being tectorium, fensterpappe and
hornglas. Tectorium consists of gall
vanized iron web covered with gelat-
nous substance and is translucent, but
not transparent. 1t is described as a
rubstance that can be bent without be-
ing broken and is both tough and flexi-
BILE. 1t is said not to be softened by the
rays of the sun, is nonsoluble, and is
not affected by severe cold. 1t is a poor
conductor of heat and is well adapted
for roofs OH account of its extreme light
ness.
When exposed to the sun, it loses its
original yellowish color in time and be-
comes harder and more durable. One
advantage is that it can bs easily re-
paired in case it is cut, does not break
and is well adapted for factory windows
and skylights for lighthouses, market
halls, verandas, transportable buildings
and for roofing.
For ordinary hotbeds pnd forcing
houses, such as are used by most florists
and market gardeners, there is another
and cheaper substitute for glass in the
SO called fensterpappe, which is tough,
strong manila paper, that may be
stretched OH large sashes or frames and
saturated by painting the exposed sur
face with boiled linseed oil until it be-
comes translucent and impervious to
water. Light wooden frames, 40 inches
in width, and of any desired length, are
provided and covered with the paper,
which is fastened by mailing at the
edges and then painted with ordinary
boiled linseed oil until the paper is so
saturated that the last coat of Oil forms
a smooth, glistening surface, like var
nish. AS soon as dry the frame is ready
for use. 1t admits sufficient light for
growing plants, does not require to be
shaded in hot sunshine, is light, dur
able, secure against breakage by hail or
ordinary accident, and, taking every.
thing into account, is said to be about
100 times cheaper than glass. 1t is
largely used by florists and market gar
deners in the district of Frankfort, and
their general verdict is strongly in its
favor, although for handsome conserva-
tories, skylights, ETC., it possesses less
durability and none Of the neatness and
elegance of tectorium.
Finally, there is a new product, called
hornglas, which has been recently pat
ented and placed on the German market.
Hornglas resembles tectorium in appear
ance. with the difference that it is thin
ner, and consequently lighter in weight,
and the insoluble gelatin with which
the wire gauze is covered is whittier and
more nearly transparent than tectorium,
although it may be colored red, green,
blue or any other tint that may be de-
sired for special purposes. It is manu-
featured i'll two qualities, one being of
heavier wire and with larger meshes
than the other. The special advantage
claimed for hornglas is that it does not
soften under sun heat and is therefore
adapted to use in any climate without
the danger of becoming so soft and adj
hesive as to retain dust and dirt. Its
uses and general characteristics are SIM
liar to those of tectorium. st. Louis
Globe-Democrat.