CERTAIN IMPROVEMENTS IN STEAM BOILERS
Year: 1859

page_text: LETTERS PATENT to James Musgrave, of the Firm of John Musgrave
and Sons, of the Globe Iron Works, Bolton-le-Moors, in the County of
Lancaster, Engineer, for the Invention of "CERTAIN IMPROVEMENTS IN
STEAM BOILERS."
Sealed the 11th April 1860, and dated the 21st October 1859.
PROVISIONAL SPECIFICATION left by the said James Musgrave at the
Office of the Commissioners of Patents, with his Petition, on the
21st October 1859.
I, JAMES MUSGRAVE, of the Firm of John Musgrave and Sons, of the Globe
Iron Works, Bolton-le-Moors, in the County of Lancaster, Engineer, do
hereby declare the nature of the said Invention for "CERTAIN IMPROVEMENTS
IN STEAM BOILERS," to be as follows:-
The nature of my Invention consists in the application of a small multi-
tubular boiler or boilers to the flue or flues of a boiler of the usual construction,
also in constructing the said small multitubular boiler so that the outer shell
or casing can be easily taken off for the purpose of examining and repairing
the tubes.
The diameter of the small multitubular boiler is rather less than that of the
flue within which it is placed, so as to leave a passage between the two for
the products of combustion; the interior of the small multitubular boiler is
connected to the interior of the main boiler by pipes placed in such wise as to,
cause a constant current in the water, thereby preventing the accumulation of

page_text: sediment. By means of these improvements the heating surface is considerably
increased, and a great saving in fuel is effected; and as the small multitubular
boiler can be removed from the flue after the flanges of the connecting pipes
are disconnected, it is evident when repairs are necessary that by employing
an extra small multitubular boiler, the damaged one can be taken out and the
extra one put in its place in a few hours, while the requisite repairs are
being made.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Musgrave in the Great Seal Patent Office on the
18th April 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
MUSGRAVE, of the Firm of John Musgrave and Sons, of the Globe Iron
Works, Bolton-le-Moors, in the County of Lancaster, Engineers, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-first day of October, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-third year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said James Musgrave, Her special licence that I, the said James Musgrave,
my executors, administrators, and assigns, or such others as I, the said James
Musgrave, my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "CERTAIN IMPROVE-
MENTS IN STEAM BOILERS," upon the condition (amongst others) that I, the said
James Musgrave, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and seals, should particularly describe
and ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause the same. to be filed in the Great
Seal Patent Office. within six calendar months next and immediately after
the date of the said Letters Patent.
NOW KNOW YE, that I, the said James Musgrave, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and. by the fol
lowing statement (that is to say) :-
The nature of my Invention consists in the application of a small multi-

page_text: tubular boiler or boilers to the flue or flues of a boiler of the usual construction;
also in constructing the said small multitubular boiler, so that the outer shell
or casing can be easily taken off for the purpose of examining and repairing
the tubes. The diameter of the small multitubular boiler is rather less than
that of the flue within which it is placed, so as to leave a passage between the
two for the products of combustion; the interior of the small multitubular
boiler is connected to the interior of the main boiler by pipes placed in such
wise as to cause a constant current in the water, thereby preventing the accu-
mulation of sediment. By means of these improvements, the heating surface
is considerably increased, and a great saving in fuel is effected; and as the
small multitubular boiler can be removed from the flue after the flanges of the
connecting pipes are disconnected, it is evident, when repairs are necessary,
that by employing an extra small multitubular boiler, the damaged one can be
taken out and the extra one put in its place in a few hours, while the requisite
repairs are being made.
And in order that my Invention may be fully understood and readily carried
into effect, I will proceed to describe the accompanying Sheet of Drawings,
reference being had to the figures and letters marked thereon.
Fig. 1 is a longitudinal section, Fig. 2 a transverse section, and Fig. 3 a
plan, also in section, of a two-flued boiler of the ordinary construction, to which
my improvements are applied. a is the outer shell or casing of the boiler;
b, b, are the flues, and c, c, the fire grates, made in the usual manner; d, d,
are two small multitubular boilers placed within and near the ends of the flues
C, C. The diameter of these small multitubular boilers is so much less than
the internal diameter of the flues as to leave sufficient space for the passage
of a portion of the products of combustion, the remainder passing through the
tubes of the multitubular boilers which are connected to the flues by the pipes
e and f. These pipes are placed at opposite ends of the multitubular boilers,
and the one is above while the other is below; by this means a constant current
is produced in the water from the main boiler, thereby preventing to a great
extent the accumulation of sediment in the multitubular boilers. The shell
or casing of the multitubular boiler is or may be connected to the tube plates
by screws or bolts, and can easily be taken off for the purpose of examining
and repairing the tubes. By means of these improvements in steam boilers,
the heating surface thereof is considerably increased, and a great saving in
fuel is effected; and as the multitubular boiler can be removed from the flue
after the flanges of the pipes e and ƒ are disconnected from the interior of the
flue, it is evident, when repairs are necessary, that by employing an extra
small multitubular boiler, the damaged one can be taken out and the extra

page_text: one put in its place in a few hours, while the requisite repairs are being
made.
Another great advantage resulting from thus applying a multitubular boiler
in the flue of an ordinary boiler is, that the shell and tubes of the multi-
tubular boiler are kept at the same temperature, consequently the expansion
and contraction are equal in all the parts, and the tubes are not liable to
work themselves loose and leak, as in multitubular boilers of the ordinary
construction.
In Figs. 1 and 3, I have shewn the plates of the flues b, b, connected by
irons made in the form of the bridge rails used on railways, so that they yield
to the expansion and contraction of the flue, thereby preventing the rivets
from working loose. I prefer the use of these bridge irons in the construc-
tion of flues to which my improvements are applied, but I make no claim
thereto, as they have been in use before the date of this Patent. I would also
remark, that although I have shewn my improvements as applied to a boiler
with two flues, they are equally applicable to boilers with a single flue, or with
more than two flues.
Having thus stated the nature of my Invention and described the
manner of performing the same, I wish it to be understood that I do not limit
myself to the details given; but what I claim is, the application of a small
multitubular boiler or boilers to the flue or flues of a boiler of the ordinary
construction, as shewn and described, or any modification of the same.
In witness whereof, I, the said James Musgrave, have hereunto set my
hand and seal, this Seventeenth day of April, in the year of our Lord
One thousand eight hundred and sixty..
JAMES MUSGRAVE. (L.D.)