IMPROVE- MENTS IN THE METHOD OF HEATING OR FIRING OVENS FOR THE MANUFACTURE OF POTTERY AND PORCELAIN BY MEANS OF GAS, AND IN APPARATUS CONNECTED THERE-- WITH
Year: 1860

page_text: PROVISIONAL SPECIFICATION left by Henry Alfred Jowett at the
Office of the Commissioners of Patents, with his Petition, on the 19th
November 1860.
I, HENRY ALFRED JOWETT, of Sawley, in the County of Derby, Civil
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE METHOD OF HEATING OR FIRING OVENS FOR THE MANUFACTURE OF
POTTERY AND PORCELAIN BY MEANS OF GAS, AND IN APPARATUS CONNECTED THERE--
WITH," to be as follows, namely:-
By the above title it will be readily comprehended that gas is the agent to
be substituted in place of the present firing system adopted by manufacturers
of the above wares, but it must also be distinctly understood that of whatever
nature the gas may be it will not in its natural state of combustion yield
sufficient or adequate heat for achieving the desideratum in question without the
united aid of atmospheric air and steam in combination with the gas, the gas
being the inflammable body, the air supplying a sufficiency of oxygen for the
support of its combustion in confined ovens, and the steam being added to
increase the heat to the intensity of the "blow pipe," and diffuse it equally but
in volume, instead of concentrating it to one point, as in the case of the blow
pipe. The construction of the burner by which the gas, air, and steam are
employed in combination will entirely depend upon the shape of the oven in
which the saggers or retorts containing the china or earthenware articles for
firing are to be placed, but by way of example, without rigidly binding myself
to the precise method herein set forth, I claim, first, the construction of a

page_text: hollow fire-clay brick with separate compartments for the introduction therein
of the three agents to be combined for producing an intensity of heat. On
one side of the hollow brick I attach in moulding the same a fire-clay tube of
two inches diameter and six inches in length, at an angle of forty-five degrees,
the end which is moulded on the brick being in the upper compartment for
gas, and the lower one being for the admission of air and steam by a transverse
division in the lower compartment of the brick. These solid bricks and hollow
brick burners will be built in the oven as bricks are now built, that is to say,
in a round oven; the first layer or circle would be the solid brick, built on the
stock or foundation bricks, the second layer would be the hollow or burner brick,
the third layer, solid brick laid upon the burner brick, and so on alternately
until the conical oven is considered of sufficient heighth, and by a series of
pipes uniting each and every hollow brick externally by short pieces of tube.
from the upright pipes, the lower ends of the latter are inserted into a circular
hollow casting, which is made in two halves, and bolted together by flanges,
This casting
and traversing externally and entirely round the circular oven.
is the receptacle for the inflammable gas, which is supplied by a main pipe
direct from the gasometer, which may be regulated by a main stop-cock. The
upright pipes are closed at the top, so that the gas passes from them through
the short connecting pipe into the upper compartment of the brick, and from
thence igniting in the interior of the oven upon the fire-clay tube, which is
moulded on the hollow brick of the oven, the gas, air, and steam will be
admitted, and perfect combustion effected in the interior of the oven, and
regulated to the greatest nicety from the exterior. Should it be found
necessary to increase the heat more than the present plan described will give,
the solid bricks may be dispensed with and hollow burner bricks substituted,
and a hollow column of fire-clay in the centre of the oven with burners all round
it from the base to the heighth of the other burners; this column to be
supplied with gas, air, and steam, by pipes or flues underneath the floor
of the oven.
Drawings and further explanations will be duly enrolled in the permanent
Sunsification