Burlington free press. [volume] (Burlington, Vt.) 1827-1865, 1843-06-02

glass of which this mosaic is composed show n
surface of from one twelfth to one fourth of an
inch square, which is however much above the
size of the pieces used in smaller mosaics. II &C.
cuped the constant labour of five skilful artists
for eight years, and cost above $4,000.
In the middle ages, stained window glass was
one of the principal decorations Of ecclesiastical
structures, and was carried to an admirable de-
gree of perfection. This art, after having fallen
much into decay, has been lately revived, and
specimens are now produced at Munich, in no
wise inferior to the finest from the middle ages.
The principal modern Improvements in glass
are in casting large plates for Mirrors afterwards
ground and polished, and in its adaptation to op.
teal purposes, to which the progress of modern
astronomy and many branches of physical science
is in great measure to be ascrbcd. The inven-
ton of achromatic object glasses for telescopes
by Dollond was an era in the art, and the Eng
fish had for many years the highest reputation
for optical instruments, but the improvements of
Guinaud in France, and Fraunhofer and his sue.
cessors in Bavaria, have led to the production of
large masses of glass of great transparency, and
perfectly homogeneous and uniform in texture
"a point of great difficulty and reffacting tele.
scopes are now made at Munich of much greater
power and excellence, than any hitherto attemp-
ted in England.
We have no direct evidence that the ancients
possessed any means of aiding the sight by opti-
cal instruments, or even that they were acquain.
ted with the magnifying power of convex trans
parent objects, but it seems impossible, that the
latter property should have escaped the notice of
their glass orkers, and the of magnifiers by
them has been inferred, with great probability,
from the extreme minuteness and delicacy of
their wrought gems and figured works in glass.
The beautifully executed figures of their lap.
daries and glass workers are often very mi
mute, that they can be appreciated only by the
aid of powerful convex lens, and it seems i'm
possible that the naked eye of the most practiscd
artist could guide the tool, direct and arrange
the threads of glass, in lines of such extreme fine
ness and precision. The possibility of accom-
plishlng this receives some support from the
known fact, that some of the best modern en-
gravers on wood use no magnfers, but the sur
face upon which they work is plane, or very near
ly so, and therefore more accessible, to speak,
in every part, to the eye, than the sunken figure
of an ntaglio, peroration in tablet of glass,
and the opinion of Winckelmann, that the ancient
artisans made use of simple lenses or some other
optical instrument, is therefore not hastily to be
rejected.
The manufacture of glass has been at all times
remarkable for the simplicity of its processes,
and the fewness Of the implements required, and
the modern Improvements in machinery have
not yet exercised much influence on its produc.
ton Lenses both concave and convex are
ground by hand, no mechanical contrivance hav.
ing been found to answer so perfectly.
A recent new application of glass has excited
some interest in Europe. 1t consists in inter-
weaving tilaments of glass with silk in such a
way as to produce flexible and highly brilliant
and beautiful texture. Specimens of this fabric
have been exhibited in this country, and it is
thought to be capable of such improvements, as
to furnish very beautiful, and not extravagan,
article of dress.
/ shall now give some account Of the arts con
cerned in the most important of manufactures
the PRODUCTION OF BOOKS. The earliest sub
stances, upon which characters were written OF
rather traced, were probably the bark of trees
thin slabs Of wood, lead, and wax tablets, ancient
specimens of all which are yet extant. But none
Of these materials are suited for receiving wr
tings of much length, and books, properly speak
ing, could not exist, until it was discovered, thai
parchment and vcllum would receive and retain
characters formed by colored fluids. The appi
cation of the Egyptian papyrus to the manutac
tnre of paper was an important step, in the pro
gress of the arts connected with literature. Pa
per of this substance bears some resemblance tc
the paper cloth of the Sandwich islands, anC
their modes of preparation are not wholly dis
similar. The Egyptian paper was formed of two
or more layers of thin slices of the pith of tho
plant, laid transversely to each other, cementet
by thin glue or sizing, and dried under a heavy
and being more durable and convenient, ant
probably also cheaper, than parchment, was il
general use in Europe until the eighth century
when cotton paper was introduced into Spain By
the Moors, and gradually supplanted the pape
of Egypt. The oldest linen paper is supposed t.
have been produced in Germany about the yea
1900. Parchment and vellum however have beef
at all times more or less in use, not only for wri
ting but for printing. Books printed on vellun
n nj ttpp hut
in Europe to strike off on vellum few copies o
works of permanent value, and these are highl,
priced, for their rarity, by bbiomanacs.
The scarcity and high price of parchment il
the middle ages not untrequcntly led the posses
sors of old manuscri pts to the original wrI
ting for the purpose of substituting what they es
teemed of greater interest and value. Manu-
script thus rewritten are called palimpsests, o
c0dices reScripti and a method has been latell
discovered Of restoring and decphering the orig
| inal characters. In this way some important los
works have been recovered, and new discoverie
| in this curious branch Of research are continual
| ly making.
The ancient form of books was the roll, lonl
! narrow strip Of parchment or papyrus written OF
one side, and attached to and rolled upon rount
stick, as is now practsed with maps. A library
of such volumes, consisting Of about 100 rolls
was found at Herculaneum, near the middle o
| the last century, and though charred, and other
wise injured, many of them have been unrolle'
and deciphered.
The present form of books is older, by man,
centuries, than the art OF printing, and very few
ancient manuscripts exist in any other form. Thu
volumes were at first bound in parchment with
out wood, pasteboard, or other stifftning, ant
this mode of binding is still sometimes practiset
| particularly in Spain. 1t is perhaps the hes
mode of binding yet discovered being not onl,
durable, but not liable to be attacked by worms
For some time after the invention of printing
books were generally bound in wood, covere,
with parchment or leather, often stamped will
the arms of the possessor or other devices, ant
frequently ornamented and strengthened will
metallic bosses, corners, and clasps. Book
were sometimes bound in gold or silver, of which
the famous CodcL 4rgenteus at upsal is re-
markable instance. This is n volume of pnrch
ment, containing a translation of part Of tn,
of the Scriptures into the Mesogothic dialect, BY
Ulphilas a bishop of that nation, who lived il
the fourth century. The volume is of great an
hqulty, perhaps even cotemporaneous with thu
translator 1t has excited much attention among
scholars, not only on account of the language, o
which it is almost the only considerable speci
men extant, but from the manner in which tn,
| contents are executed. The letters are in silver
and to the eye appear to have been impressed o
stamped with punches, but most antiquares arr
at present of opinion, that they were produced
hv n h.,, 10 ~