gaze beholds "two or
three vast circles, that have their revolving satellites like moons,
each on its own axis, and each governed by master wheels. Watch them for
any length of time and you might find yourself presently going round and
round with them until you whirled yourself out of existence, like the
gyrating maiden in the fairy tale."

In this type of grinding machine one mill stone rotates on a fixed
stone. The cacao nib falls from a hopper through a hole in the centre of
the upper stone and, owing to the manner in which grooves are cut in the
two surfaces in contact, is gradually dragged between the stones. The
grooves are so cut in the two stones that they point in opposite
directions, and as the one stone revolves on the other, a slicing or
shearing action is produced. The friction, due to the slicing and
shearing of the nib, keeps the stones hot, and they become sufficiently
warm to melt the fat in the ground nib, so that there oozes from the
outer edge of the bottom or fixed stone a more or less viscous liquid or
paste. This finely ground nib is known as "mass." It is simply liquified
cacao bean, and solidifies on cooling to a chocolate coloured block.

[Illustration: SECTION THROUGH GRINDING STONES.]

This "mass" may be used for the production of either cocoa or chocolate.
When part of the fat (cacao butter) is _taken away_ the residue may be
made to yield cocoa. When sugar and cacao butter are _added_ it yields
eating chocolate. Thus the two industries are seen to be
inter-dependent, the cacao butter which is pressed out of the mass in
the manufacture of cocoa being used up in the production of chocolate.
The manufacture of cocoa will first be considered.

(_i_) _Pressing out the excess of Butter._

The liquified cacao bean or "mass," simply mixed with sugar and cooled
until it becomes a hard cake, has been used by the British Navy for a
hundred years or more for the preparation of Jack's cup of cocoa. It
produces a fine rich drink much appreciated by our hardy seamen, but it
is somewhat too fatty to mix evenly with water, and too rich to be
suitable for those with delicate digestions. Hence for the ordinary
cocoa of commerce it is usual to remove a portion of this fat.

[Illustration: A CACAO PRESS.
Reproduced by permission of Messrs. Lake, Orr & Co., Ltd.]

If "mass" be put into a cloth and pressed, a golden oil (melted cacao
butter) oozes through the cloth. In practice this extraction of the
bu