The liquid is boiled for a time, and then put into a cistern excluded
from the light, having holes at the bottom into which long tubes
of thick twilled cotton are fastened, through which the solution
runs as bright as water; they all hang down into another cistern
below, also kept from the light, from which it is pumped up into the
evaporating apparatus--a copper vessel entirely air-tight, heated by
steam and having a powerful air-pump attached to it by which all the
vapour and air are removed as the syrup becomes hot; this is called
a “vacuum pan” (see engraving), and by this the syrup is condensed
to the proper consistence, and is put into moulds of the shape the
loaf is to be, having holes at the lower part which are plugged up,
the syrup as it cools forming a solid mass of crystals; these moulds
are arranged in rows over a channel leading to a proper receptacle,
the plugs are taken out from the holes at the bottom of each and some
pure concentrated syrup is poured on to the upper part; this slowly
descending filters through the sugar, carrying with it any “caramel”
that may have formed, finally escapes at the hole, and runs into the
cistern; this completely whitens the sugar, and gives it a brighter
and coarser grain. The loaves are then taken from the moulds, dried
in an oven at a gentle heat, and finally packed in paper for sale.
If the pointed ends are discolored or ragged the loaf is put into
a lathe (fig. 3) and the end turned to a proper figure or cut off.