AN IMPROVEMENT IN FURNACES TO BE
Year: 1868

page_text: LETTERS PATENT to Clarence Delafield, of Factoryville, in the County
of Richmond, and State of New York, in the United States of
America, for the Invention of "AN IMPROVEMENT IN FURNACES TO BE
Sealed the 20th November 1868, and dated the 22nd May 1868.

page_text: the same, and have made solemn Declaration that I am the true and
first Inventor thereof.
NOW KNOW YE, that I, the said Clarence Delafield, do hereby
declare that the following Complete Specification, under my hand and
seal, fully describes and ascertains the nature of the said Invention, and
in what manner the same is to be performed, in and by the following
statement, that is to say :-
My Invention appertains more especially to the manufacture of the
yellow oxide of lead, and consists of a furnace made substantially as
follows, reference being had to the Drawing accompanying this Speci-
fication, and making part of the same.
In the Drawing above referred to Figure 1 is a transverse vertical
section through the grate bars, fire chamber, melting pans, and oxydizing
chamber, and Figure 2 is a longitudinal section through the same,
showing the direction of the flues.
The fire chamber of this furnace, the grate bars of which are shown
by g, is formed in brickwork in the front-end thereof, and is made about
four feet wide, and equal in length to the entire width of the furnace.
This fire chamber is covered with three pans which reach back over the
flues thereof, as shown in the Drawing by a, a, b. Thesc pans con-
stitute the crown or cover of the fire-box, and are the receptacles in
which the metallic lead is melted and oxydized. Over the top of these
pans a cover is placed, consisting of an iron plate A supported on the
brickwork, the sides and back of which are carried up about eighteen
inches above the pans, leaving the front open, by which a low broad
chamber is formed in which the oxydizing is carried on, and which I
style the oxydizing chamber. In this chamber I arrange in suitable
bearings two shafts c, c, one in the front and the other in the rear
thereof, exactly parallel with each other, and on each of which I arrange
and secure three chain wheels d, d, d, adjusting those on the front shaft
precisely on the same plane or parallel with those on the rear shaft,
thus forming three pairs of chain wheels, over each of which I draw an
endless chain e, e, e, and on these chains across them and exactly
parallel with the shafts aforesaid I secure a skimmer, shown by b.
This skimmer is carried along and over the chain wheel, dropping in
the rear ends of the pans, and moving forward in them skims the oxide
off of the melted lead and throws it out over the front ends of the
pans, leaving it to fall down in front of the furnace, the lower edge

page_text: of the skimmer being serrated to allow it to pass readily through the
melted lead. The Drawing shows the doors of the fire chamber made
in the front wall of the furnace showing three doors, but I prefer to
have but one door, and that in the side wall of the furnace at the end
of the fire chamber, or in case the chamber be too long to fire con-
veniently there may be two doors, one in each end of the fire chamber
through the side walls of the furnace, and the ash-pit door instead of
being in front, as appears in the Drawing, should also be in the side,
by which the front of the furnace may be also kept clean to receive
the oxide of lead as it falls from the pans.
Now in operating this furnace the atmospheric air by which the
oxydization is carried on also supplies the furnace by which the com-
bustion of the fuel is supported, that is to say, the air enters the mouth
of the oxydizing chamber and passes back over the melted lead, carrying
the fumes therefrom with it through the the flues down. through the
flues B and into the furnace, and out through the flue into the
chimney, as illustrated by the arrows. By these means it will be seen
that the attendant is never exposed to the deleterious fumes of the lead,
that the lead is constantly supplied with a current of fresh or pure air,
that the smoke and gas of the furnace never come in contact with the
melted lead, and that the same current of air which passes over the lead
pans also passes through the furnace and supplies it with the oxygen
necessary for the combustion of the fuel, the ash-pit door being never
opened for any purpose but to clean the ashes from under the grate bars.
The advantage resulting from the use of this furnace is a very pure
clean oxide of lead, produced with great rapidity, and at very small
cost of fuel and labor, and without detriment to the health of the
operator.
Having now described and ascertained the nature of my Invention,
I claim as new herein and as my Invention,―
First. Making an open-mouthed oxydizing chamber with a flue in the
rear end or side thereof, to insure a draft of fresh air over the surface
of the melted lead, and with the bottom thereof made of metal in the
shape of a pan or paus, and with the bottom of said oxydizing chamber
so made in relation to the fire-box or chamber as to form the cover or
covers thereof.
Second. Combining in said oxydizing chamber a pair of shafts and
endless chains fitted with a skimmer to travel with said chains over said

page_text: shafts and skim the oxide off from the surface of the melted metal,
substantially as described.
Third. Making and arranging the flue from the oxydizing chamber
and the flues of the fire chamber in relation to each other, so as to draw
the air and fumes from the oxydizing chamber through the fire and up
the chimney.
In witness whereof, I, the said Clarence Delafield, have hereunto
set my hand and seal, this Twenty-fourth day of April, A.D.
One thousand eight hundred and sixty-eight.
CLARENCE DELAFIELD. (L.S.)