IMPROVEMENTS IN OR APPLICABLE TO LOCOMOTIVE, MARINE, AND OTHER STEAM BOILERS FOR THE PURPOSE OF PROMOTING THE COMBUSTION OF FUEL AND OBTAINING INCREASED EVAPORATING POWER
Year: 1879

page_text: LETTERS PATENT to James Wavish, of Leytonstone, in the County of Essex,
for the Invention of "IMPROVEMENTS IN OR APPLICABLE TO LOCOMOTIVE,
MARINE, AND OTHER STEAM BOILERS FOR THE PURPOSE OF PROMOTING THE
COMBUSTION OF FUEL AND OBTAINING INCREASED EVAPORATING POWER."
Sealed the 16th December 1879, and dated the 19th June 1879.
PROVISIONAL SPECIFICATION left by the said James Wavish at the Office
of the Commissioners of Patents on the 19th June 1879.
'
JAMES WAVISH, of Leytonstone, in the County of Essex. "IMPROVEMENTS IN
OR APPLICABLE TO LOCOMOTIVE, MARINE, AND OTHER STEAM BOILERS FOR THE
PURPOSE OF PROMOTING THE COMBUSTION OF FUEL AND OBTAINING INCREASED
EVAPORATING POWER."
My Invention relates to the apparatus for facilitating the proper combustion of
fuel, in respect of which Letters Patent were granted to me dated the 4th January
1875, No. 89.
In applying the said apparatus to steam boilers it has been customary to con-
struct it in the form of a series of vertical bars which surround an elongated
opening in a plate constituting the bottom of the grate, and are surmounted by
another plate which forms a cover to the chamber thus constituted, a space being
left between each two consecutive bars, so as to form outlets into and among the
fuel for the air introduced through the said opening.
It has been found in practise that the said cover becomes rapidly deteriorated
and destroyed under the action of the heat to which it is subjected, and requires
frequent renewal.
Now my present Invention has for its object counteracting this tendency to
rapid deterioration of the cover and at the same time increasing the evaporating
power of the boiler; and it consists for that purpose in constructing the cover
hollow and connecting it with the water space in the boiler in such a manner that
the water shall be caused to enter and fill and constantly circulate through the

page_text: cover, thus protecting it from injury from the action of the heat at its exterior, and
also contributing to the available heating surface of the boiler. It is preferred to
connect the cover at the fire door end with the lower part of the boiler, and at the
fire bridge end with the upper part of the boiler, so as to promote the required
circulation.
My present Invention is particularly adapted for use in locomotive and marine
steam boilers, but it is also applicable to steam boilers of other descriptions. By
its employment the advantages of my former Invention in facilitating the proper
combustion of fuel are retained, whilst at the same time the apparatus is rendered
more durable, and an augmentation of the evaporating power of the boiler is 1
secured.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said James Wavish in the Great Seal Patent Office on the 19th
December 1879.
JAMES WAVISH, of Leytonstone, in the County of Essex. "IMPROVEMENTS IN
OB APPLICABLE TO LOCOMOTIVE, MARINE, AND OTHER STEAM BOILERS FOR THE
PURPOSE OF PROMOTING THE COMBUSTION OF FUEL AND OBTAINING INCREASED
EVAPORATING POWER."
My said Invention relates to the apparatus for facilitating the proper combustion
of fuel, in respect of which Letters Patent were granted to me, dated the Fourth
January, One thousand eight hundred and seventy five, No. 39.
In applying the said apparatus to steam boilers it has been customary to con-
struct it in the form of a series of vertical bars which surround an elongated
opening in a plate constituting the bottom of the grate, and are surmounted by
another plate which forms a cover to the chamber thus constituted, a space being
left between each two consecutive bars, so as to form outlets into and among the
fuel for the air introduced through the said opening.
It has been found in practice that the said cover becomes rapidly deteriorated
and destroyed under the action of the heat to which it is subjected, and requires
frequent renewal.
Now my present Invention has for its object counteracting this tendency to
rapid deterioration of the cover, and at the same time increasing the evaporating
power of the boiler; and it consists for that purpose in constructing the cover
hollow and connecting it with the water space in the boiler in such a manner that
the water shall be caused to enter and fill and constantly circulate through the
cover, thus protecting it from injury from the action of the heat at its exterior, and
also contributing to the available heating surface of the boiler.
My present Invention is particularly adapted for use in locomotive and marine
steam boilers, but it is also applicable to steam boilers of other descriptions.
And in order that my said Invention may be fully understood I shall now
.proceed more particularly to describe the same, and for that purpose shall refer to
the several Figures on the annexed Sheet of Drawings, the same letters of reference
indicating corresponding parts in all the Figures.
Figure 1 of my Drawings represents a half end elevation and half transverse
vertical section of a portion of a marine boiler having applied thereto the improve-
ments which form the subject of my said Invention; Figure 2 is a longitudinal
section and Figure 3 a horizontal section of the same, both corresponding to
Figure 1; Figures 4, 5, and 6 illustrate the application of my said Invention to a
Cornish boiler, Figure 4 being a half end elevation and half transverse vertical
section of the boiler, Figure 5 a longitudinal section of a portion of the same, and
Figure 6 a detail of one of the water chambers hereinbefore referred to and herein-
after more fully described.
Referring to Figures 1, 2, and 3, A. is the shell of the marine boiler; B, B, are
the fire boxes; C, the smoke boxes; D, the fire tubes; and E, the chimneys, all of
which may be generally arranged in any usual or suitable manner; F are the grates
which, as constructed upon the principle of my said former Invention, each consist
of vertical bars a arranged at opposite sides of an elongated opening b in a plate o
constituting the bottom of the grate; the bars are secured together and to end
plates d, d, by bolts e, and are surmounted by a cover, so as to form a chamber f
into which the air for supporting combustion is introduced through the opening b,
the said air thence passing through spaces a¹ left between the bars into and among
the burning fuel in the grate. Now my present Invention relates chiefly to the
construction and arrangement of the cases surmounting the said bars, and consists
in constructing them hollow, so as to form water spaces or chambers, as shown at G,
and connecting them with the water space in the builer in order to maintain a
circulation of water through the boiler and the said chambers. The connection of

page_text: the chambers G with the boiler water space may be made in various ways. In the
example illustrated in Figures 1, 2, and 3, a pipe g at the fire door end of each
chamber G is carried upwards into the upper part of the boiler water space, and
another pipe g¹ at the opposite end is passed through the firebridge H and extended
downwards into the lower part of the boiler water space; the water is thus caused
to enter and fill and constantly circulate through the chambers or hollow covers G,
thereby protecting them from injury from the action of the external heat, and at
the same time contributing to the available heating surface of the boiler and
equalizing the expansion of the boiler plates.
In the Specification to Letters Patent granted to me, dated the Twenty sixth
November, One thousand eight hundred and seventy five, No. 4106, there is
described the use of an air chamber beneath the grate for the introduction of air
from the external atmosphere. In carrying out my present Invention, and in
particular in the application of the same to marine boilers, it is found advantageous
to close the ash pits at h, thus forming air chambers I, and to supply air thereto for
the purpose of supporting combustion by means of pipes i and a fan or blower from
the external atmosphere in lieu of the necessary air being drawn from the stoke
holo as in the ordinary manner.
I make no claim however to the use of closed ash pits and a forced draft as
forming any part of my present Invention.
Figures 4, 5, and 6 illustrate the application of my Invention to a double flued
Cornish boiler, B, B, being the flues containing the grates F constructed in the
manner hereinbefore described.
In this example the pipes g, g', communicating respectively with the upper and
lower parts of the boiler water space are carried out at the front of the boiler, and
a partition k (see detail Figure 6), having an aperture 1, is provided in each of the
water chambers G in order to further promote the circulation of the water through-
out the extent of the said chambers.
Although however I have shewn different arrangements of the pipes g, gl, in the
examples of marine boiler and Cornish boiler illustrated, I wish it to be understood
that the said arrangements of pipes may be used indiscriminately for either type of
boiler; also that the partition in the water chambers may be used or omitted in
either arrangement; and further, that the pipes and chambers may be otherwise
modified, according to circumstances.
By means of my present Invention the advantages of my former Invention in
facilitating the proper combustion of fuel are retained, whilst at the same time the
apparatus is rendered more durable, and an augmentation of the evaporating power
of the boiler and an equalization in the expansion of the boiler plates are secured.
Having now described and particularly ascertained the nature of my said In-
vention, and the manner in which the same is or may be used or carried into
effect, I would observe in conclusion that what I consider to be novel and original,
and therefore claim as the Invention secured to me by the herein before in part
recited Letters Patent is,-
In steam boilers the combination with fire grates constructed as herein set forth
of water chambers or spaces communicating with the water space of the boiler and
arranged in relation to the said fire grates, substantially in the manner and for the
purposes herein before described.
In witness whereof, I, the said James Wavish, have to this my Specification
set my hand and seal, the Fifteenth day of December, One thousand eight
hundred and seventy nine.