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The Process. In the preparation of glass in the smelters three
substances are used, namely, sand, soda ash and lime. The sand is
imported from Fontainbleau in France, the reason being that it is free
from iron. Local sand has a percentage of iron, and if this were used
it would cause discolouration of the glass and other peculiarities. This
Fontainbleau sand is as white almost as driven snow and is exceedingly
fine in texture—almost like castor sugar. The soda ash and lime are
obtained locally. These substances are passed through a mixing
machine in accordance with the required proportions, and are fed into
the smelting furnace by hand—the workmen using a shovel—where it
remains for five days. At the end of that time the furnace presents a
fascinating appearance. The temperature, which is at 1,200 degrees
Centigrade, leads eventually to the production of a wonderful scene;
the whole consists of a shimmering, viscid, ruddy, molten mass, highly
incandescent, of a consistence of that of treacle. There are two
processes concerned with the manufacture of the bottles, namely, the
power and hand machines. Taking the power machine first, this is of
the rotary type and is fed directly from the smelter. A globe of the
molten mass runs into the trough ; the amount released by a cutter
represents the exact volume required for the mould. Immediately the
molten mass passes into the mould two things happen: a dye presses
down creating a hollow in the mass, and at the same time lateral
pressure is exerted which gives it the desired form in accordance with
the particular type of bottle which is being made. The horizontally
revolving table gives turn in a circular direction, the mould opens, and
the bottle, still red hot, is picked up neatly at the bottle neck by a
projecting metal arm. This swings over and deposits the bottle on a
broad moving belt until finally quite a number of bottles are seen on
this belt. These are picked up by a scoop and transferred to the
annealer; this latter is simply a slow cooling process, which, if not
used, would lead to the brittle bottles smashing easily. The annealing
process imparts toughness to the bottles. It is really a long compartment
in which the bottles pass through from a fair temperature (created
by gas heating) to a normal temperature. In the hand work process
the machine is fed by a man who scoops out a certain quantity of the
mass from the smelter with a ladle. It may be said that this process
is used for special orders where a few thousand special kinds of bottles
have been ordered. This process is in contrast to the other one in
which enormous numbers of stock bottles are turned out as a routine,