fuel to be prohibitive in competition with coal and
gas. An electric roaster was demonstrated at the Food Conservation Show
in New York, in 1918, at a time when the federal government was urging
the necessity of conserving coal as a war economy measure. The inventor
claimed that his machine would reduce roasting cost, improve the flavor
and the aroma, and maintain a constant and easily controlled heat. He
declared also that when roasted in his devices, less coffee was required
for brewing.

An expert coffee-roasting-machinery man who has been working on the
development of a practical electric roaster says that if it were
possible to bake the coffee in an oven, just as the baker does his
bread, the fuel cost would then compare favorably with that of gas or
coal. It is because the heat chamber must have an exhaust to release the
chaff and smoke that the use of electricity to replace the heat loss
proves prohibitive when compared with coal or gas.

In all types of coal and coke burning roasters, the cylinders are heated
by a fire underneath; while in gas roasters, the flame may be underneath
or within the cylinder itself. Roasters in which the heat is within the
cylinder are known as direct-flame or inner-heated machines. All three
systems are used in the United States and Europe.

_Facts About Coffee Roasting_

The modern commercial roasting outfit is as near fool-proof as human
genius has been able to devise. The more advanced types are almost
automatic in operation, and are designed to insure uniformity of roasts.
In such machines the green coffee is conveyed to the roasting cylinder
by means of bucket elevators, which pour the beans into a feed hopper.
From the feed hopper, the coffee is dumped through the opening in the
front head-piece into the cylinder. The cylinder is perforated, and has
inside flanges which keep tossing the coffee about while the cylinder
revolves, so that the coffee will not burn during the roasting process.

[Illustration: GERMAN GAS COFFEE-ROASTING PLANT EQUIPPED WITH
IDEAL-RAPID MACHINES]

To roast coffee by coal or coke usually requires from twenty-five to
thirty minutes, depending on the moisture-content of the beans; whether
they are spongy or flinty; whether a light, medium, or dark roast is
desired; and on the skill of the operator. Gas roasting requires from
fifteen to twenty minutes. The quicker the roast, the better the coffee,
is the opinion of many trade leaders, one of whom[