IMPROVEMENTS IN ROASTING COFFEE AND OTHER SUBSTANCES AND IN APPARATUS THEREFOR."
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by William Parnall at the Office of the
Commissioners of Patents on the 1st January 1881.
WILLIAM PARNALL, of Victoria Street, Temple, in the City and County of
Bristol, Grocer's Outfitter. "IMPROVEMENTS IN ROASTING COFFEE AND OTHER
SUBSTANCES AND IN APPARATUS THEREFOR."
My Invention consists mainly as follows:-
Mounted upon two standards (or sides) preferably of cast iron, each of which are
cast in one piece and held by horizontal bars, is a cylinder or drum, both ends of
which are covered with a wire network of about one eighth of an inch in the
square hole or mesh. This network is held in position at each end by a frame and
spindle. Upon these frames are fixed, either by rivets or nuts and bolts, a body of
network of the same dimensions or thereabouts as before described. This network
forms the circumference or outside of the revolving cylinder. Fastened to the
standards or sides by means of brackets is a pipe, preferably of wrought iron, of
from two to six inches in diameter, and upon this pipe is fixed a number of gas
jets or burners. Over each of these burners is fixed a piece of iron pipe of about 3/4
to 1 inch in diameter, and about six inches in length, with four or more air holes
at the end nearest the burners before mentioned.
When gas is forced through this combined atmospheric burner, and a light placed
in front of same, a blue flame of gas and air is produced. This blue flame I arrange
to come in contact with the outside of the revolving cylinder of iron net work, the
heat from which flame passing through the network to the interior of the cylinder
roasts the coffee or other substance therein contained. For roasting some substances
I omit the wire net work, and make instead the body of the cylinder of sheet
iron.
The cylinder before described is enclosed by a sheet iron casing, which casing is
held in position by two or more sheet or wrought iron bands, at each end of which
is a screwed piece of round iron'; this screwed iron is attached to the frame on both
sides by means of a nut.
At the top of the before mentioned enclosure, or in any other suitable position,
is a sliding door held in position by two sheet iron plates or guides; these guides
are fixed to the casing by means of rivets.

page_text: A similar arrangement I adopt underneath the chimney, which is attached to the
said casing for the purpose of checking the outlet of heat from the body of the
cylinder or interior revolving drum. The front standard or side has a sheet iron
door fixed by means of a nut and bolt at its base; upon this bolt the door rests
and partly revolves to allow the operator to draw out the slide of the revolving
drum.
This sheet iron door is prevented from springing out of position by means of a
strap of wrought iron fixed to the interior of the frame, and grooved to allow
free working of said door. Momentum is given to the revolving drum by means
of a cog wheel and pinion, the handle being cast onto and forming part of the
pinion by this arrangement.
This handle will pass the sample extractor which passes through the axle in
which the cog wheel is attached. In the face of the cog wheel is a hole of
about 3/4 inch diameter, which receives a stop pin. This stop pin when passed
in the hole in cog wheels, enters a boss forming part of the frame, and holds the
• revolving cylinder in position, so that the sliding door of the cylinder may be more
readily removed,