take the place of natural sun-drying on some plantations.

In the dry method, the husks are removed either by hand (threshing and
pounding in a mortar, on the smaller plantations) or by specially
constructed machinery, known as hulling machines.

[Illustration: Coban Pulper in Tachira, Venezuela]

_The Wet Method--Pulping_

The wet method of preparation is the more modern form, and is generally
practised on the larger plantations that have a sufficient supply of
water, and enough money to instal the quite extensive amount of
machinery and equipment required. It is generally considered that
washing results in a better grade of bean.

In this method the cherries are sometimes thrown into tanks full of
water to soak about twenty-four hours, so as to soften the outer skins
and underlying pulp to a condition that will make them easily removable
by the pulping machine--the idea being to rub away the pulp by friction
without crushing the beans.

On the larger plantations, however, the coffee cherries are dumped into
large concrete receiving tanks, from which they are carried the same day
by streams of running water directly into the hoppers of the pulping
machines.

At least two score of different makes of pulping machines are in use in
the various coffee-growing countries. Pulpers are made in various sizes,
from the small hand-operated machine to the large type driven by power;
and in two general styles--cylinder, and disk.

The cylinder pulper, the latest style--suggesting a huge
nutmeg-grater--consists of a rotary cylinder surrounded with a copper or
brass cover punched with bulbs. These bulbs differ in shape according to
the species, or variety, of coffee to be treated--_arabica_, _liberica_,
_robusta_, _canephora_, or what not. The cylinder rotates against a
breast with pulping edges set at an angle. The pulping is effected by
the rubbing action of the copper cover against the edges, or ribs, of
the breast. The cherries are subjected to a rubbing and rolling motion,
in the course of which the two parchment-covered beans contained in the
majority of the cherries become loosened. The pulp itself is carried by
the cover and is discharged through a pulp shoot, while the pulped
coffee is delivered through holes on the breast. Cylinder machines vary
in capacity from 400 pounds (hand power) to 4,800 pounds (motive power)
per hour.

Some cylinder pulpers are double, being equipped with rotary screens or
oscillating