The Redwood gazette. [volume] (Redwood Falls, Minn.) 1873-1940, 1875-05-13
Unbreakable Glass.

n Paris correspondent OF the Philadel-
phla Bulletin writes: Some curious ex-
periments in glass, which were quite
novel to myself, though | cannot say
whether they may be so to what is tech
nically called the trade" took place be-
fore the French Academy of Sciences at
the Institute last week, and seem de-
serving of some mention. If l am re-
peating only what is we'll known already,
or has been even carried to a further
extent by American manufacturers of
the article in question, | must apologize
for my ignorance; but what was exhib-
tied at the French Institute seemed very
extraordinary, and was regarded by all
present as representing something which
has been considered as hitherto unattain-
able. There was brought in what is re-
garded in most French domestic estab-
lishments as an article of lndispersa-
BILE household necessity, familiar under
the name of a Ve're d'Euu, and which
consists of stand, a water bottle, two
glasses, and sugar-basin, all of glass,
to which is generally appendeda smaller
bottle for fem doramge, the whole being
intended, of course, for the fabrication
of that most universal of "d1inks"
amongst all classes OF French peo-
pie, from the orator in the trib-
une to the ccncierge's wife in her
| toge, u glass of can sacree. Well,
all these different ohjects-water-bot-
tie, glasses, sugar-basin, stand itself
were taken up separately by NJ. de Lu-
bac, the well-known member of the So
ciety for the announcement of French
Manufactures, and on the responsibility
of the inventor, NJ. de la Bastie, pitched
one after the other to a considerable dis
lance, and, to our no small establishment,
without giving rise to any occasion for
"picking up the pieces" They all, in
fact, remained unbroken and uninjured.
The secret of "unbreakable glass;" that
great boon to the peace of families and the
nerves of housekeepers, seemed to be
solved. There were several ladies look
interest they took in discovery which
promised security to many of the most
cherished objects of their chdnabre-a a. couch
er and their dinner tables. Even bobectes,
or sconces for candles, of the very light
est and thinnest description, were thrown
down upon the floor, from which they re-
bounded again without the slightest inju-
ny. The secret of imparting this invalua-
able property to glass does not, it ap-
pears, consist in any particular method of
fabrication. Any sort OF glass can be
rendered unbreakable by q subsequent
process to which it has to be submitted
for this purpose. The process consists
in "tempering' or hardening" the glass
after it is made (tremper is the French
word used to express the operatlon) by
immersing it in solution at the heat ut
which it usually melts. The composition
of the solution aud the heat at which it
is to be applied vary with the quality of
the glass which is to be submitted to it.
OF what the composition consists, the
exact mode of using it and of procuring
its results, the inventor, of course, told
US nothing; but a large usine de tremepage,
or g.ass-tempering works, is now in
course OF erection at Pont d'Ain, in the
Ain, near Bourg, for carrying on the
process on large scale. am told that
at the Society for the Encouragement of
Manufactures itself the experiments
were lately exhibited in a still more re.
markable manner, and that while plates
of ordinary glass there broke to pieces
by fall of one yard, those of Item
pered" glass fell uninjured from height
of four yards, and when even struck
violently with hammer broke only like
flint or granite.