930 
and many different machines. In what 
follows, reference is made to what the 
writer himself saw. 
When thoroughly dry, the coffee beans 
are gathered into heaps, put in sacks, and 
loaded on a hand-car, which travels on 
small tracks from the terreiros to a large 
building containing the storage bins and 
the machinery. The beans are first 
dumped into large bins containing coffee 
of various grades, and from these they 
are carried, as needed, to the first of the 
final stages. The first machine is a ven- 
tilator, in which an upward current of 
air, driven at a high velocity by a blower, 
carries the dust, outer shells, and lightest 
beans upward, but lets the heavy beans 
and any remaining stones and sand fall 
to the bottom, where a sieve, in rapid 
oscillation to and fro, separates the beans 
from the sand. 
The modern machinery now in use in 
Brazil for removing the two inner en- 
velopes from the coffee beans is of many 
different patterns and makes, but the ob- 
ject is the same in all forms, viz., to 
manipulate the beans between two sur- 
faces, one of them in motion, until by 
friction the envelopes, or shells, come off 
and are carried in one direction while the 
beans go in another. Coffee which, be- 
cause too dry, or too green, or imperfect, 
could not be pulped, is, as already noted, 
dried on the terreiros. It is then sent 
through the hulling machine just as if 
the outer skin and pulp had already been 
removed. 
The general principle on the huller is 
very simple. A metal cylinder with a 
grooved or convoluted surface rotates 
inside of an adjustable metal cover, also 
grooved on the inside. The coffee beans, 
passing between these two grooved sur- 
faces with much friction, gradually have 
their coverings rubbed off. Other hullers 
have a sort of Archimedes screw ar- 
rangement of varying sizes of thread, 
while others, again, produce the desired 
result by the friction of an iron or steel 
network against a rubber surface. 
REMOVING THE DUST AND HULLS 
From the hulling machine the coffee 
goes through a second ventilator, which 
THE NATIONAL GEOGRAPHIC MAGAZINE 
throws off the dust and hulls, leaving the 
coffee beans clean and ready for sorting, 
and then to a separator. This, in a com- 
mon form, is a hollow wire or copper 
cylinder in three or four compartments, 
all communicating, each compartment 
having holes of a certain definite size. 
The cylinder is gently inclined and is 
kept revolving, the coffee beans traveling 
slowly down the incline. Sometimes 
there is a spiral worm running down the 
central portion of the cylinder, which 
helps the beans to travel down the slope. 
Those which fit the openings in any one 
compartment fall out of the cylinder 
there; those which do not, slide alone 
into the next compartment, and so on 
until they meet with perforations through 
which they can escape. ‘There is thus a 
first classification, according to size. 
Another form of separator, sometimes- 
used alone or in addition to the one just 
described, consists of a series of wire 
sieves with mesh of various sizes ar— 
ranged vertically so that each successive 
sieve slopes off at a small angle in the 
opposite direction from that of the sieve 
above, each division being slightly over- 
lapped by the one above. ‘The coffee 
beans fall in at the top, into the uppermost 
sieve. This, kept in rapid vibration to 
and fro, lets any beans which fit the 
mesh of the first division fall through, 
while those which do not fit these open- 
ings are shaken down onto the next 
sieve, and so on, all the way to the bot- 
tom. In this way the beans may be 
mechanically sorted into six or eight 
categories. They fall directly from the 
machine into the bags through funnel- 
shaped troughs. 
The final stage is the catador, in which 
the beans are subjected to a strong up- 
ward current of air, which separates. 
them according to weight into two (or 
more) categories. There is usually a 
glass window in the front of the catador, 
through which the beans may be seen 
carried up by the strong draft, the 
heavier ones falling, the lighter ones ris- 
ing. The strength of the draft can, of 
course, be regulated. 
A very ingenious single conmbininem 
machine, recently installed at Santa Veri— 
