m
piping sufficient to make them boil. A second pipe passes into them,
making a single turn at the bottom of the vessel; this is pierced on
the lower side with small holes, through which a stream of carbonic
acid gas is forced.

This decomposes the saccharate of lime, which has been formed in
consequence of the large excess of lime added to the clarifiers.

The lime is precipitated as carbonate. When precipitation has
ceased, steam is turned on, and the whole made to boil; this expels
any excess of carbonic acid; the liquor is then run off, undergoes a
similar partial filtration to that mentioned above, and is then
passed through the charcoal filters to be decomposed. The sugar made
by this process, directly from the beet-root juice, is nearly white.
The molasses is re-boiled as often as six times; each time
undergoing a clarification and filtration through animal charcoal.
And the proceeds of the last re-boiling is certainly in appearance
not worse than a great deal of muscovado I have seen shipped from
Trinidad.

In this work there are about 150 people employed. The work goes on
night and day, one gang replacing the other. The whole evaporation
is done by two vacuum pans, each 61/2 feet in diameter, 80,000
kilogrammes of beet-root are used daily, from which about 6,000
kilogrammes of sugar are obtained, equal to about 6 tons English
weight.

In these and every other works I visited--eight in all--the
centrifugal machines were in use, and had in most cases been so for
two years; those lately made have been much simplified in
construction, and work admirably. Cail & Co., of Paris, are the
makers; their charge is 3,000 francs for each machine (L120 stg.).
They require about one and a half horse power each. As they are
wrought in France, one machine is about equal to work off a ton and
a half of sugar daily, working all the 24 hours. Mr. Cail recommends
a separate engine for those machines; so that they can be used at
any time, independent of the other machinery. The charge put into a
machine is about 80 kilogrammes, from which about 30 to 35
kilogrammes of dry sugar is obtained; the calculation is, I believe,
40 per cent. I weighed some of the baskets of sugar taken out after
drying, and found them 35 kilogrammes. Sugar intended for the
machine is never concentrated