Emerald Isle, to be used by the peasants for the weak infusion called
"miserables."

Now comes the important process of grinding, performed between
horizontal mill-stones, the friction of which produces heat and melts
the "butter," while it grinds the "nibs" till the whole mass flows,
solidifying into a brittle cake when cold.

The thick fluid of the consistency of treacle flowing from the
grinding-mills is poured into round metal pots, the top and bottom of
which are lined with pads of felt, and these are, when filled, put
under a powerful hydraulic press, which extracts a large percentage of
the natural oil or butter. The pressure is at first light, but as soon
as the oil begins to flow the remaining mass in the press-pot is
stiffened into the nature of indiarubber, and upon this it is safe to
place any pressure that is desired. As it is not advisable to extract
all the butter possible, the pressure is regulated to give the
required result. In the end a firm, dry cake is taken from the press,
and when cool is ground again to the consistency of flour; this is the
"cocoa essence" for which the firm of Cadbury is so well known in all
parts of the world.[13]

Between cocoa and chocolate there are essential differences. Both are
made from the cocoa nib, but whereas in cocoa the nibs are ground
separately, and the butter extracted, in chocolate sugar and
flavourings are added to the nib, and all are ground together into a
paste, the sugar absorbing all the superfluous butter. If good quality
cocoa is used, the butter contained in the nib is all that is needful
to incorporate sugar and nib into one soft chocolate paste for
grinding and moulding, but in the commoner chocolates extra cocoa