IM- PROVEMENTS IN STEAM AND OTHER BOILERS
Year: 1869

page_text: PROVISIONAL SPECIFICATION left by Charles Markham at the Office
of the Commissioners of Patents, with his Petition, on the 26th
February 1869.
I, CHARLES MARKHAM, of Brimington, in the County of Derby,
Engineer, do hereby declare the nature of the said Invention for "IM-
PROVEMENTS IN STEAM AND OTHER BOILERS," to be as follows:-
This Invention has, firstly, for its object so to construct a steam or
other boiler of a number of tubes of cast iron that none of the joints
by which the several tubes are bolted together or otherwise attached to
one another shall be exposed to the action of the fire by which the
tubes are heated. For this purpose I form the boiler of a number of
sets of tubes, each composed of two horizontal tubes at a distance apart
from one another, and connected at intervals by vertical tubes, which
are cast in one piece with them. Several such sets of cast tubes are set
up side by side with the ends of all the horizontal pipes passing through
two parallel brick walls which form the side walls of the boiler furnace;
one end of each of the horizontal tubes is, by preference, closed by a cap
or cover whilst the opposite ends of all the lower horizontal tubes are
connected to a pipe to which the feed water is admitted, and the
opposite ends of all the upper horizontal tubes are similarly connected to

page_text: a pipe which forms a steam chamber. The several sets of tubes are
thus each connected to a feed water pipe and to a steam chamber, and
all the joints by which they are connected to these pipes are exterior of
the boiler furnace, so that they are not affected by the heat of the fire.
In each of the upper horizontal tubes openings are formed above each of
the vertical tubes which pass down from them; these openings are fitted
with covers, by removing which the interior of the vertical tubes can
readily be cleaned. The upper and lower horizontal tubes can also
readily be cleaned by removing the caps or covers from their ends. The
fire-grate for heating a boiler so constructed is by preference placed
below one of its ends, and the products of combustion from it are led
along below the bottom of the boiler to its further end, and are then led
back through the spaces between the vertical tubes, or the flues might
be otherwise arranged. The openings between the sides of the tubes of
each row of horizontal tubes are closed by fire-brick or otherwise in
order the better to expose the several vertical tubes to the action of the
fire; the vertical tubes of one casting are by preference placed opposite
to the spaces between the vertical tubes of the adjacent castings, and in
order that this may be effected, and yet that all the castings may be of
one pattern, I cast each set of tubes with its two horizontal tubes which
project out beyond the vertical tubes longer on one side of the vertical
tubes than the other by a distance equal to the distance between the
vertical tubes, so that if sets of tubes so cast are placed together side by
side with the alternate sets placed end for end the vertical tubes of one
set will come opposite the spaces between the adjacent sets when the
ends of all the horizontal tubes are in a line with one another, so that
they can all readily be bolted or otherwise connected to flanges on one
tube running along in front of them. In place of a boiler such as is
above described being made up of sets of cast tubes such forms of boilers
may also be made of tubes of wrought metal connected into sets as
above described, and with the joints by which they are connected to the
water supply pipe and to the steam pipe exterior of the boiler furnace, so
as not to be affected by the heat of the fire. Boilers for hot water
apparatus and such like purposes may also be constructed in a similar
manner to that above described.,