128 
THE PRINCIPAL FLOOR. 
Indian trades. The art o£ making glass beads was first dis- 
covered in Murano, where the trade is still great. Here also 
will be found pieces of enamelled, painted and etched glass, &c_ 
Etching on glass may be effected by covering the glass with a. 
coating of wax, and then, with a needle removing it along the 
lines to be etched. The drawing being formed, the glass is 
exposed to the action of hydro-fluoric acid, liberated from fluor- 
spar by the action of sulphuric acid. Most glass, however, is 
now etched by means of the sand blast. 
Toughened glass is prepared by plunging the finished article 
into oil or melted fat at a high temperature. Glass may be also 
hardened by rapid and uniform cooling, as practised by 
Mr. Siemens, of Dresden. 
Ancient Glass. Case 53. — Specimens of Assyrian, Babylonian, 
Egyptian, Greek, and Roman glass are here exhibited. 
The cinerary urns of green glass will be inspected with much 
interest : and of these Mr. Apsley Pellatt writes, “ The round 
vases are of elegant forms, with covers and two double handles,, 
the formation of which must convince any one capable of appre- 
ciating the difficulties which even the modern glass-maker would 
have to surmount in executing similar handles, that the ancients 
were well acquainted with the art of making round glass 
vessels.” One of the bottles found at Nismes has been formed 
by being blown in a mould. The lachrymatories , which pro- 
bably contained the unguents and aromatics which it was usual 
to deposit with the dead, have been so called from the romantic 
notion that these bottles, usually found in tombs, were filled 
with the tears of the mourners. 
The Roman glass beads, from the number of them which have 
been discovered in various parts, must have been much in use. 
Here, too, will be found some examples of so-called “ Druidic beads.” 
These beads were also called Glain Neidyr, from glain pure and 
holy, and neidyr a snake. It is curious to find these beads in 
the ancient British tombs, in the graves of our Roman con- 
querors, in the tumuli of the Anglo-Saxons, and at the present 
day in the Ashantee district of Africa; while a bead in all 
respects similar, is made in Venice. 
Venetian Glass. Cases 71, 72. — Venice, for a long period 
during the middle ages, was celebrated throughout Europe for 
its glass. Familiar with the manufacture from an early date, 
the Venetians, on the capture of Constantinople, in 1204, pro- 
fited by their intercourse with the East, and glass factories soon 
became so numerous at Venice, that towards the latter part of 
the thirteenth century they were removed to the adjacent island 
of Murano. During the fourteenth century, the art was prin- 
cipally directed to the production of beads and other trifles, but 
a fresh impulse was given to the manufacture on the fall of the 
Eastern empire ; and during the fifteenth and sixteenth centuries 
Venice produced those peculiar examples of glass work, which, 
from their ingenuity of design and delicacy of execution, 
