The Houston daily post. [volume] (Houston, Tex.) 1886-1903, 1899-01-29

in cutting the lenses from natural stone.
which was commonly called pebble glass
This was done by cutting or grinding the
Lenses from a crystal substance, which Was
round in considerable quantities in differ
ent countries. the best coming from Brazil,
South America. These stone spcctaccs
are very superior to the ordinary glass, in
many respects, rs they are very hard and
take very brilliant polish, but they have
these disadvantages which remain for the
scientist to overcome. This rock being OF
the natural formation, has grain to 1t
the same as is found In wood and unless
| the greatest of care Is used in cutting tho
glass the right way of the grain, there are
more or less imperfections which no
amount of surface polishing can obviate.
| But within the last twenty years this has
| been done away with and we now have
what Is called the french crystal lens,
| which is produced to the greatest perfec-
ton by certain French manufacturer.
In the manufacturing of these glassca.
| which are used for superior lenses, such
| as spectaCles, Photographic, microscopic
| and telescope lenses II has become an art.
| and is done by reducing the finest material
| obtainablc for lenses to condition whore
! Eli foreign elements can be taken out ut
! It, and II is then put In the form of glass
| ready foi grinding for whatever purpose
| II may be desired Now comes the work,
| by u slow process of grinding these pieces
of glass. about two inches square aud
| tbree-quarters of an inch thick, by ma
| cbinery to the certain curves desired, 10
| be snre these are done by machinery and
| IN large numbers. where similar lenses are
TO be made of like curvptures. But when
1t comes to making lenses of odd curyn.
lures. where two or more combinations
must be included In n single lens, this
work must all be done by hand; and, as
can be imagined, particularly If you have
ever tried 10 grind piece of glass, is very
slow and tcdtous work and requires tho
utmost skin. a
These lenses ground by hand are called
compounds. and n single glass may possess
two or more distinct features, which com
bination is utterly impossible to obtain In
lenses that are not ground for individual
cases. Men who make n science of fitting
glasses today will tell you that with the
exception of few simple troubles 1t Is
necessary to have lenses ground for almost
every patient and by so doing great bene-
Ats can be derived from lenses very much
milder than would be necessary II ready
made glasses were prescribed.
OF course you are not going to know this
from tho man who does not make II bust
ness TO Mt your eyes and simply wishes to
sell YOU a pair of spectaces the same as
he would sell you any article of merchan-
disc. such rs ring, pin or the like. and
expects to make his profit from the trim
mipgs, Did you ever give this matter
thought enough to go into the office OF an
expert optcian and make some Inquiries
as to the differences In glasses, or go
through the proceedings of having your
eyes examined by the modern methods in
use today by the best opticians?
To enumerate the different methods aud
the endless appliances that are in use at
the present time for testing sight and eX-
aiming eyes. many of which have a great
deal of virtue, would take more time than
we now have space for. We predict that
the day of the spectacle peddler with his
case OF glasses and little focusing rod is
fast drawing to nm end.
CHANGE IN SIZE.
One fact which has struck many people
ms rather curious is the change in the size
of spoctacles. which has been made in the
Inst few years. This can be assigned in q
general way to the fact that every year
adds something to the perfecting of
glasses. and as they are now ground much
thinner than heretofore they can be made
larger without adding more weight than
was previously contained In the old-style,
small eyed lenses 1t can be readily seen
that there Is n very great advantage in
having the lenses large, as 1t gives the
wearer much larger field OF vision and
does not hamper one with the constant
seeing of the rims. The fact that our we'll
to do people are the first to take advantage
OF these improvements, II is quite natural
that the large glasses should become the
STYLE and while many look at II as fad,
| Il does not depreclate the tendency 10
larger glasses, and even now the smaller
lenses are looked upon as uncomfortable
and out OF date. particularly by those who
have had some experience in the matter.
AMERICAN FRAMES,
! Now word about the frames. This
| has grown to be great industry, In GER
tain parts OF the country, particularly In
| Massachusetts,. whore there are number
of large factories which employ thousands
of people in this line alone. The French
may have the best of us In producing nne
| lenses. but there is no country in the world
| that can excel us In the manufacture of
| frames. Even the frames made In Eng
| land are not as perfect as our American
| make. There are many different metals
! used In this art tor such II has become),
commencing with steel or brass and ending
In the finest OF solid gold But the metal
which has given tho best satisfaction is
composition Of metals similar to silver in
color. which for general durability cNccls
any single metal that We have and besides
does not corrode. This is called alilmni
cum Many have asked why the pure
aluminium Is not used for this purpose.
II Is because aluminium in itself Is alto
gether too bulky md viii not hold the
fine screws that are necessary In putting
together a pice appearing frame,
Another frame which is coming very
gensrally into use aud which Is considered
by opticians as very practical and dur
able article is the gold flled frame, Taere
have been gold plated and gold filled
frames on the market for years. but Il Is
only recently that a real credtable article
| has been made
We are Indebted to Dr. Seymour for
much interesting matter on the subject Of
eycsight and many readers have become
interested IN these articles aud have called
on him. fully approaching the advantages
offered by his presence In he city. This
! Is indicated by the increasing numbers
who daily avail themselves OF his Invita-
ton, and Or. Seymour has decided TO pro-
long his visit and viii again give free con
sultation during the coming week.
| Teachers mt waxahachic.
Waxahachie, Texas. January 2s,--Thc