IMPROVEMENTS IN LIGHTING RAILWAY CARRIAGES WITH GAS, AND IN THE APPARATUS EMPLOYED THEREIN
Year: 1873

page_text: In the Matter of Letters Patent granted to JOHN CLAYTON MEWBURN, of 169,
Fleet Street, in the City of London, Patent Agent and Consulting
Engineer, for the Invention of "IMPROVEMENTS IN LIGHTING RAILWAY
CARRIAGES WITH GAS, AND IN THE APPARATUS EMPLOYED THEREIN."
A communication to him from abroad by Julius Pintsch, of Berlin, Prussia,
Mechanical Engineer, bearing date the 22nd day of September 1873,
No. 3101.
DISCLAIMER AND MEMORANDUM OF ALTERATION as proposed to be
entered by Julius Pintsch, Gas Engineer, of Berlin, in the German Empire,
Adolph Preuss, Banker, also of Berlin, James Pellatt Rickman, Glass Manu-
facturer, of No. 17, St. Bride's Street, in the City of London, and Hugo
Pischon, Engineer, of Metropolitan Chambers, New Broad Street, in the City
of London, pursuant to the Statutes in that case made and provided.
WHEREAS Her Majesty Queen Victoria, by Her Letters Patent under the
Great Seal of the United Kingdom of Great Britain and Ireland, bearing date, at
Westminster, the Twenty-second day of September, 1873, in the thirty-seventh
year of Her reign, did give and grant unto the said John Clayton Mewburn, his
executors, administrators, and assigns, the sole privilege, for the term of fourteen
years thence next ensuing, of making, using, exercising, and vending, within the
United Kingdom of Great Britain and Ireland, the Channel Islands, and Isle of
Man, the said Invention of "IMPROVEMENTS IN LIGHTING RAILWAY CARRIAGES
WITH GAS, AND IN THE APPARATUS EMPLOYED THEREIN." A communication to him
from abroad by Julius Pintsch, of Berlin, Prussia, Mechanical Engineer:
And whereas, in pursuance of a proviso in the said Letters Patent contained, the
said John Clayton Mewburn, did, within six calendar months next after the date
[Price 4d1

page_text: of the said Letters Patent, cause a Specification or instrument in writing under his
hand and seal, purporting to describe and ascertain the nature of the said Inven-
tion, and in what manner the same was to be performed, to be duly filed in the
Great Seal Patent Office :
And whereas the said Letters Patent were assigned to Julius Pintsch, who on
the 25th November 1874, filed in the Great Seal Patent Office a Disclaimer and
Memorandum of Alteration of the said Specification:
And whereas the said Letters Patent were afterwards assigned to, and became,
and now are vested in us, the said Julius Pintsch, Adolph Preuss, James Pellatt
Rickman, and Hugo Pischon :
And whereas since the filing of the said Disclaimer and Memorandum of
Alteration, we, the said Julius Pintsch, Adolph Preuss, James Pellatt Rickman,
and Hugo Pischon, have discovered that in consequence of a clerical error the
alteration actually made in the Specification as altered and amended by the said
Disclaimer and Memorandum of Alteration does not correspond with the alteration
intended to be made by the same, and have farther discovered that the said Specifi-
cation when so altered and amended might be objected to on the ground that the
Invention intended to be secured by the said Letters Patent is not in the Amended
Specification defined with sufficient precision:
And whereas the title of the said Letters Patent might be objected to as including
subject matter which forms no part of the Invention intended to be expressed
thereby:
And whereas we are desirous of defining the Invention intended to be claimed
under the said Letters Patent with greater precision:
We hereby disclaim the whole of the alterations made in the original Specification
by the Disclaimer and Memorandum of Alteration filed on November 25th, 1874, and
strike out the words "Having now described" and the words following down to and
including the words "regulating cone in page 2, and also in pages 5 and 6 of the
Queen's Printers' copy of such Disclaimer and Memorandum of Alteration, and we
disclaim and alter the title and parts of the Specification of the said Letters Patent
in manner following, that is to say :-
In the title after the words "improvements in " we insert the words "apparatus
2 for," and we omit the words "and in the apparatus employed therein," and the
title when so altered will read, "Improvements in Apparatus for Lighting Railway
Carriages with Gas."
65
"
"
"
In the Specification referring to the Queen's Printers' copy thereof as originally
filed, in page 5, line 2, we omit the words "more especially;" at page 5, line 3, we
omit the words "in the first place;" at page 5, line 4, we omit the word "and;" at
page 5, line 5, for the words "and in the second place of" we substitute the word
with;" at page 5, line 14, we insert the word "and" after the semicolon; at
page 5, line 15, we omit the semicolon after the reference letter "c" and the words
a regulating;" at page 5, line 18, for the word "metal" we substitute "metals;
at page 6; line 6, for the comma after "Sheet I." we substitute the close of a
parenthesis; and at the end of the line after the reference letter "a
we insert a
semicolon; at page 6, line 15, we omit the word "and." At the end of the Specifi-
cation we insert the following words :-"The nature of the said Invention and the
manner in which the same is to be performed having been thus described, it is to
"be understood that no claim is made generally to the lighting of railway carriages
"by gas compressed in reservoirs thereon, nor is any claim made to any regulator
"other than a regulator such as is referred to above as being represented in
"Sheets I. and II. of the annexed Drawings, and constructed as herein-before
"described; and no claim is made to any of the parts thereof as being new other
<<
combined regulating place c and cone d and a new and peculiarly
A
" than those above indicated as being respectively a new and peculiarly employed
"and prepared leather membrane f and a pressure spring 9 of peculiar make, and
employed for the purpose of constant regulation."
st

page_text: TLEBS 0IU JW VPSPII-PI
We will read as ICWS
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN CLAYTON
MEWBURN, of 169, Fleet Street, in the City of London, Patent Agent and Mechanical
Engineer, send greeting.
WHEREAS Her Most Excellent Majesty Queen Victoria, by Her Letters Patent
bearing date the Twenty-second day of September, in the year of our Lord One
thousand eight hundred and seventy-three, in the thirty-seventh year of Her reign,
did for Herself, Her heirs and successors, give and grant unto me, the said John
Clayton Mewburn, Her special license that I, the said John Clayton Mewburn, my
executors, administrators, and assigns, or such others as I, the said John Clayton
Mewburn, my executors, administrators, or 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 "IMPROVEMENTS IN APPARATUS FOR LIGHTING RAILWAY
CARRIAGES WITH GAS," (a communication from Julius Pintsch, of Berlin, Prussia,
Mechanical Engineer), upon the condition (amongst others), that I, the said John
Clayton Mewburn, 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 John Clayton Mewburn, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, reference being had to the accompanying Drawings, that is to
say:
All systems hithereto in use for the lighting of railway carriages with gas are
based on the principle of having the supply of gas, whether in a compressed or non-
compressed state, in one carriage only, in one or more vessels, from which the
burners of the other carriages are fed. Besides, the great loss of gas caused by the
many connections of joints which are unavoidable in the conducting pipes, there is
another great disadvantage, and this is, that by the system in question, the dis-
connection of a carriage from a train, or the coupling on of another carriage is
always attended with difficulties, and therefore impedes the traffic on the railway.
Now according to the system herein-after explained, avoiding the drawbacks
above mentioned, every carriage is lighted separately by gas, and in such a manner
that one carriage is quite independent of the others, and carries a sufficient quantity
of gas with it to feed, say, 5 burners for a period of 33 hours. This is accom-
plished by the employment of oil gas of the strongest illuminating power, which is
very economical when in a highly compressed state, with the gas pressure regulator
herein-after described, which makes the reduction of the compressed gas at about
6 atmospheres down to the burning point (about 15" water column pressure)
possible.
The regulator is represented in Sheets I. and II. of the annexed Drawings,
Figures 1 and 2 being vertical sections shewing the regulator in and out of action
respectively, and Figure 3 being a plan view, the membrane herein-after described
being removed.
The regulator consists principally of a divided cast-iron vessel a, of a metal dust
regulating
receptacle b, and of a new and peculiarly combined place c and cone d.
A
The regulating place is made of bronze, and operating against it for shutting off
the stream of gas is the regulating cone, made of 86 per cent. tia, 5 per cent. copper,
and
per cent. antimony. Through the agency of the metals just described alone
is it possible to attain a durable and absolute shutting off of the stream of gas; and
it may be remarked here, that when bronze is employed against bronze or similar

page_text: hard metals the shutting off becomes imperfect, owing to the atoms of dust; and
besides, caoutchone or other materials of a similar nature are soon destroyed by the
carbon and hydrogen contained in the gas.
The regulator consists further of a lever connection e, and of a new and pecu-
liarly employed and prepared leather membrane f. This membrane, consists of the
best sheep skin, made tight by being stretched in a solution of gutta percha and
grease. Other membranes, whether of caoutchouc or any other materials, would be
destroyed, owing to the quantity of oxygen and hydrogen contained in the gas.
And lastly, the regulator consists of a pressure spring g of peculiar make, and
employed for the purpose of constant regulation. The spring is made of two layers
of watch-spring steel, its bearings being at h, and it is in connection with the
lever e.
By means of this proportionately great length it is in a position to fulfil
the functions hereafter described. A direct pressure weight would increase the
vibrations caused by the driving of the train so much as to extinguish the gas-
lights instantly.
The apparatus for the regulation of the pressure on gas when compressed gas is
employed has to fulfil the following functions:-The compressed gas passes the dust
receptacle, goes through the channel of the regulating place c, against the new and
peculiar regulating cone d, then through the 6 passages of the conductor of the
regulating cone d (see the detail views on Sheet I.), and fills the cast-iron vessel a
through the pressure of the gas streaming in the leather membrane f, and with it
the lever connection e and the regulating cone d are raised, and the spring g effects
by means of its tension the pressure necessary for burning, and regulates the
difference of pressure at the same time arising from the motion of the carriages.
Sheet III. shows a part of a railway carriage lighted by gas according to this
Invention. The oil gas being compressed to about 6 to 8 atinospheres is kept in a
reservoir A, or, if considered necessary, there can be two reservoirs affixed to the
bottom of the carriage, which can be filled after a lapse of from 24 to 36 hours by
means of a suitable compression pump at those railway stations where the gas is
manufactured. The gas goes from this reservoir by pressure to the above described
regulator, which is likewise affixed to the bottom of the carriage, as seen at B, and
issuing from the latter with the usual burning pressure it is conductedd by pipes
fixed to the sides and top of the carriage direct to the several burners.
The nature of the said Invention, and the manner in which the same is to be
performed having been thus described, it is to be understood that no claim is made
generally to the lighting of railway carriages by gas compressed in reservoirs
thereon, nor is any claim made to any regulator other than a regulator such as
is referred to above as being represented in Sheets I. and II. of the annexed
Drawings, and constructed as herein-before described; and no claim is made to
any of the parts thereof as being new, other than those above indicated as being
respectively a new and peculiarly combined regulating place c and cone d, and a
new and peculiarly employed and prepared leather membrane f and a pressure
opening g of peculiar make, and employed for the purpose of constant regulation.
In witness whereof, I, the said John Clayton Mewburn, have hereunto set my
hand and seal, this Twenty-second day of January, One thousand eight
hundred and seventy-four.
J. C. MEWBURN. (L.S.)
In witness whereof, we, the said Julius Pintsch, Adolph Preuss, James Pellatt
Rickman, and Hugo Pischon, have hereunto set our hands and seals, this
Seventeenth day of April, in the year of our Lord One thousand eight
hundred and seventy-eight.
JULIUS PINTSCH. (L.S.)
ADOLPH PREUSS. (L.S.)
J. P. RICKMAN. (L.S.)
HUGO PISCHON.
(L.S.)

page_text: I hereby grant my fiat, giving leave to the above-named Julius Pintsch, Adolph
Preuss, James Pellatt Rickman, and Hugo Pischon, the assignees of the said Letters
Patent, to file in the Great Seal Patent Office, with the Specification to which the
same relates, the above written Disclaimer and Memorandum of Alteration.
Dated the Twentieth day of December 1878.
JOHN HOLKER,
Attorney-General.

page_text: In the Matter of Letters Patent granted to John Clayton
Mewburn, of 169, Fleet Street, in the City of London, Patent
Agent and Consulting Engineer, for the Invention of "IM-
PROVEMENTS IN LIGHTING RAILWAY CARRIAGES WITH GAS, AND IN THE
"APPARATUS EMPLOYED THEREIN," a communication to him from
abroad by Julius Pintsch, of Berlin, Prussia, Mechanical
Engineer, bearing date the 22nd day of September 1873,
No. 3101.
-
.DISCLAIMER AND MEMORANDUM OF ALTERATION as proposed to
be entered by JULIUS PINTSCH, of Berlin, Prussia, Mechanical Engineer,
ursuant to the Statutes in that case made and provided.
WHEREAS Her Majesty Queen Victoria, by Her Letters Patent
under the Great Seal of the United Kingdom of Great Britain and
[reland, bearing date at Westminster, the Twenty-second day of
: a
. >
35

page_text: September, One thousand eight hundred and seventy-three, in the
thirty-seventh year of Her reign, did give and grant unto the said John
Clayton Mewburn, his executors, administrators, and assigns, the sole
privilege, for the term of fourteen years thence next ensuing, of
making, using, exercising, and vending, within the United Kingdom
of Great Britain and Ireland, the Channel Islands, and Isle of Man,
the said Invention of "IMPROVEMENTS IN LIGHTING RAILWAY CARRIAGES
WITH GAS, AND IN THE APPARATUS EMPLOYED THEREIN," a communication to
him from abroad by Julius Pintsch, of Berlin, Prussia, Mechanical
Engineer:
"
And whereas in pursuance of a proviso in the said Letters Patent con-
tained, the said John Clayton Mewburn, did within six calendar months
next after the date of the said Letters Patent cause a Specification or
instrument in writing under his hand and seal, purporting to describe
and ascertain the nature of the said Invention, and in what manner the
same was to be performed, to be duly filed in the Great Seal Patent
Office:
And whereas the said Letters Patent have been assigned to, and
became, and now are vested in me the said Julius Pintsch:
And whereas since the filing of the Specification, I, the said Julius
Pintsch, have discovered that part of the said Invention as described
in the said Specification may be objected to on the ground that as
described it was not new; in consequence thereof I hereby disclaim and
alter part of the said Specification in manner following, that is to
say :-
k
In page 6 of the Queen's Printer's Copy of the Specification, after the
words "the several burners" in line 22, I add the words " Having thus
"described the nature of the said Invention, and in what manner the
same is to be performed, I would have it understood that no claim is
"intended to be made to the construction of a gas regulator in which a
"flexible diaphragm or membrane is connected to a lever working a regu-
lating valve, nor to any part of such a regulator except to the use of a
spring applied to the lever thereof, the mode herein described of pre-
"paring the flexible membrane or diaphragm and the composition herein
"described of the regulating cone."
66
66
And the said Specification when disclaimed and altered will read as
follows:-

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent
filed by the said John Clayton Mewburn, in the Great Seal Patent
Office on the 23rd January 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I JOHN
CLAYTON MEWBURN, of 169, Fleet Street, in the City of London, Patent
Agent and Consulting Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-second day of September, in
the year of our Lord One thousand eight hundred and seventy-three,
in the thirty-seventh year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said John Clayton Mewburn,
Her special licence that I, the said John Clayton Mewburn, my executors,
administrators, and assigns, or such others as I, the said John Clayton
Mewburn, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times there-
after 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 In-
vention for "IMPROVEMENTS IN LIGHTING RAILWAY CARRIAGES WITH GAS, AND
IN THE APPARATUS EMPLOYED THEREIN," (a communication from Julius
Pintsch, of Berlin, Prussia, Mechanical Engineer,) upon the condition
(amongst others) that I, the said John Clayton Mewburn, 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 John Clayton Mewburn, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement thereof, reference being had to the accom-
panying Drawings, that is to say :-
All systems hitherto in use for the lighting of railway carriages with
gas are based on the principle of having the supply of gas, whether in a
compressed or a non-compressed state, in one carriage only, in one or more

page_text: vessels from which the burners of the other carriages are fed. Besides
the great loss of gas caused by the many connections of joints which are
unavoidable in the conducting pipes, there is another great disadvantage,
and this is that by the system in question the disconnection of a carriage
from a train or the coupling on of another carriage is always attended
with difficulties, and therefore impedes the traffic on the railway.
Now according to the system herein-after explained, avoiding the
drawbacks above mentioned, every carriage is lighted separately by gas,
and in such manner that one carriage is quite independent of the others,
and carries a sufficient quantity of gas with it to feed say 5 burners for
a period of 33 hours. This is accomplished more especially by the
employment in the first place of oil gas of the strongest illuminating
power, and which is very economical when in a highly compressed state,
and in the second place of the gas pressure regulator herein-after
described, which makes the reduction of the compressed gas at about 6
atmospheres down to the burning point (about 15" water column
pressure) possible.
The regulator is represented in. Sheets I. and II. of the annexed
Drawings, Figures 1 and 2 being vertical sections shewing the regulator
in and out of action respectively, and Figure 3 being a plan view, the
membrane, herein-after described, being removed.
The regulator consists principally of a divided cast-iron vessel a, of a
metal dust receptacle b, of a new and peculiarly combined regulating
place c, and a regulating cone d. The regulating place is made of
bronze, and operating against it for shutting off the stream of gas is the 2
regulating cone made of 86 per cent. tin, 5 per cent. copper, and 9 per
cent. antimony. Through the agency of the metal just described alone is
it possible to attain a durable and absolute shutting off of the stream of
gas, and it may be remarked here that when bronze is employed against,
bronze or similar hard metals the shutting off becomes imperfect owing a
to the atoms of dust, and besides caoutchouc or other materials of a
similar nature are soon destroyed by the carbon and hydrogen contained
in the gas.
The regulator consists further of a lever connection e, and of a new
and peculiarly employed and prepared leather membrane f. This 3
membrane consists of the best sheep skin made tight by being stretched
in a solution of gutta percha and grease. Other membranes, whether

page_text: of caoutchouc or any other materials, would be destroyed owing to the
quantity of oxygen and hydrogen contained in the gas.
g
;
And, lastly, the regulator consists of a pressure spring 9 of peculiar
make, and employed for the purpose of constant regulation. The spring
is made of two layers of watch spring steel, its bearings being at h, and
it is in connection with the lever e. By means of its proportionately
great length it is in a position to fulfil the functions hereafter described.
A direct pressure weight would increase the vibrations caused by the
driving of the train so much as to extinguish the gas lights instantly.
the
The apparatus for the regulation of the pressure on gas when com-
pressed gas is employed has to fufil the following functions:-The
compressed gas passes the dust receptacle, goes through the channel of
the regulating place c against the new and peculiar regulating cone d,
then through the 6 passages of the conductor of the regulating cone d
(see detail views on Sheet I.) and fills the cast-iron vessel a through
the pressure of the gas streaming in the leather membrane f, and with
it the lever connection e and the regulating cone d are raised, and the
spring g effects by means of its tension the pressure necessary for
burning, and regulates the difference of pressure at the same time
arising from the motion of the carriages.
A
Sheet III. shews a part of a railway carriage lighted by gas according
to this Invention. The oil gas being compressed to about 6 to 8
atmospheres is kept in a reservoir A, or, if considered necessary, there
can be two reservoirs affixed to the bottom of the carriage, which can'
be filled after a lapse of from 24 to 36 hours by means of a suitable
compression pump at those railway stations where the gas is manu-
factured. The gas goes from this reservoir by pressure to the above-
described regulator, which is likewise affixed to the bottom of the
carriage, as seen at B, and issuing from the latter with the usual burning
pressure it is conducted by pipes fixed to the sides and top of the
carriage direct to the several burners.
Having thus described the nature of the said Invention, and in what
manner the same is to be performed, I would have it understood that
no claim is intended to be made to the construction of a gas regulator in
which a flexible diaphragm or membrane is connected to a lever working
a regulating valve, except to the use of a spring applied to the lever
thereof, the mode herein described of preparing the flexible membrane or

page_text: LETTERS PATENT to John Clayton Mewburn, of 169, Fleet Street,
in the City of London, Patent Agent and Consulting Engineer, for
the Invention of "IMPROVEMENTS IN LIGHTING RAILWAY CARRIAGES WITH
GAS, AND IN THE APPARATUS EMPLOYED THEREIN."-A communication from
abroad by Julius Pintsch, of Berlin, Prussia, Mechanical Engineer.
Sealed the 14th November 1873, and dated the 22nd September 1873.
PROVISIONAL SPECIFICATION left by the said John Clayton Mewburn
at the Office of the Commissioners of Patents, with his Petition,
on the 22nd September 1873.
I, JOHN CLAYTON MEWBURN, of 169, Fleet Street, in the City of
London, Patent Agent and Consulting Engineer, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN LIGHTING RAILWAY
"to be as
CARRIAGES WITH GAS, AND IN THE APPARATUS EMPLOYED THEREIN,"
follows:-
All customs hitherto in use for the lighting of railway carriages with

page_text: -
gas are based on the principle of having the supply of gas, whether in a
compressed or a non-compressed state, in one carriage only, in one or
more vessels, from which the burners of the other carriages are fed.
Besides the great loss of gas caused by the many connections or joints
which are unavoidable in the conducting pipes there is another great
disadvantage, and this is that by the system in question the disconnec-
tion of a carriage from a train, or the coupling on of another carriage, is
always attended with difficulties, and therefore impedes the traffic on
the railway.
. Now according to the system herein-after explained, avoiding the
drawbacks above mentioned, every carriage is lighted separately by gas,
and in such manner that one carriage is quite independent of the others,
and carries a sufficient quantity of gas with it to feed, say, 5 burners, for a
period of 33 hours. This is accomplished more especially by the employ-
ment, in the first place, of oil gas of the strongest illuminating power,
and which is very economical when in a highly compressed state; and
in the second place of the gas pressure regulator, herein-after described,
which makes the reduction of the compressed gas at about 6 atmospheres
down to the burning point (about 15" water column pressure) possible.
The regulator consists principally of a divided cast-iron vessel of a
metal dust receptacle, of a new and peculiarly combined regulating
place and a regulating cone. The regulating place is made of bronze,
and operating against it for shutting off the stream of gas is the
regulating cone, made of 86 per cent. tin, 5 per cent. copper, and 9 per
cent. antimony. Through the employment of the metal just described
alone is it possible to attain a durable and absolute shutting off of the
stream of gas? and it may be remarked here that when bronze is
employed against bronze, or similar hard metals, the shutting off
becomes imperfect owing to the atoms of dust, and besides, caoutchouc
or other materials of a similar nature are soon destroyed by the carbon
and hydrogen contained in the gas.
The regulator consists, further, of a lever connection and of a new and
peculiarly employed and prepared leather membrane. This membrane
consists of the best sheep skin, made tight by being stretched in a
solution of gutta percha and grease. Other membranes, whether of
caoutchouc or any other materials, would be destroyed owing to the
quantity of oxygen.and hydrogen contained in the gas.

page_text: And, lastly, the regulator consists of a pressure spring of peculiar
make, and employed for the purpose of constant regulation. The spring
is made of two layers of watch spring steel, and it is in connection with
the lever before referred to. By means of its proportionately great
length it is in a position to fulfil the functions here after described.
A direct pressure weight would increase the vibrations caused by the
driving of the train so much as to extinguish the gas lights instantly.
The apparatus for the regulation of the pressure on gas, when com-
pressed gas is employed, has to fulfil the following functions:-The
compressed gas passes the dust receptacle, goes through the channel of
the regulating place against the new and peculiar regulating cone, then
through the six passages of the conductor of the regulating cone, and
fills the cast-iron vessel. Through the pressure of the gas streaming in
the leather membrane, and with it the lever connection and the regulating
cone, are raised, and the spring effects by means of its tension the
pressure necessary for burning, and regulates the difference of pressure
at the same time arising from the motion of the carriages. The oil gas
being compressed to about 6 to 8 atmospheres is kept in a reservoir; or
if considered necessary there can be two reservoirs affixed to the bottom
of the carriage, and which can be filled after a lapse of from 24 to 36
hours by means of a suitable compression pump at those railway stations.
where the gas is manufactured. The gas goes from this reservoir by
pressure to the above described regulator, which is likewise affixed to
the bottom of the carriage, and issuing from the latter with the usual:
burning pressure it is conducted by pipes to the sides and top of the
carriage direct to the several burners.
SPECIFICATION in pursuance of the conditions of the Letters Patent
filed by the said John Clayton Mewburn in the Great Seal Patent
Office on the 23rd January 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
CLAYTON MEWBURN, of 169, Fleet Street, in the City of London, Patent
Agent and Consulting Engineer, send greeting.

page_text: our Lord One thousand eight hundred and seventy-three, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Clayton Mewburn, Her special
licence that I, the said John Clayton' Mewburn, my executors, adminis-
trators, and assigns, or such others as I, the said John Clayton
Mewburn, 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 "Im-
PROVEMENTS IN LIGHTING RAILWAY CARRIAGES WITH GAS, AND IN THE APPARATUS
EMPLOYED THEREIN," (a communication from Julius Pintsch, of Berlin,
Prussia, Mechanical Engineer) upon the condition (amongst others) that
I, the said John Clayton Mewburn, 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 John Clayton Mewburn, do hereby
declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained
in and by the following statement thereof, reference being had to the
accompanying Drawings, that is to say:-
All systems hitherto in use for the lighting of railway carriages with
gas are based on the principle of having the supply of gas, whether in a
compressed or a non-compressed state, in one carriage only, in one or
more vessels, from which the burners of the other carriages are fed.
Besides the great loss of gas caused by the many connections of joints,
which are unavoidable in the conducting pipes, there is another great
disadvantage, and this is, that by the system in question the disconnec-
tion of a carriage from a train, or the coupling on of another carriage,
is always attended with difficulties, and therefore impedes the traffic on
the railway.
Now according to the system herein-after explained, avoiding the
drawbacks above mentioned, every carriage is lighted separately by gas,
and in such manner that one carriage is quite independent of the others,

page_text: and carries a sufficient quantity of gas with it to feed, say, 5 burners, for
a period of 33 hours. This is accomplished more especially by the
employment, in the first place of oil gas of the strongest illuminating
power, and which is very economical when in a highly compressed state ;.
and in the second place of the gas pressure regulator, herein-after
described, which makes the reduction of the compressed gas at about
6 atmospheres down to the burning point (about 15" water column
pressure) possible.
The regulator is represented in Sheets I. and II. of the annexed
Drawings, Figures 1 and 2 being vertical sections, shewing the regulator
in and out of action respectively; and Figure 3 being a plan view, the
membrane, herein-after described, being removed.
The regulator consists principally of a divided cast-iron vessel a; of a
metal dust receptacle 6; of a new and peculiarly combined regulating
place c; and a regulating cone d. The regulating place is made of
bronze, and operating against it for shutting off the stream of gas is the
regulating cone, made of 86 per cent. tin, 5 per cent. copper, and 9 per
cent. antimony. Through the agency of the metal just described alone
is it possible to attain a durable and absolute shutting off of the stream
of gas; and it may be remarked here that when bronze is employed
against bronze, or similar hard metals, the shutting off becomes imperfect
owing to the atoms of dust, and besides caoutchouc or other materials
of a similar nature are soon destroyed by the carbon and hydrogen con-
tained in the gas.
'
The regulator consists, further, of a lever connection e; and of a new
and peculiarly employed and prepared leather membrane f. This mem-
brane consists of the best sheep skin, made tight by being stretched in a
solution of gutta percha and grease. Other membranes, whether of
caoutchouc or any other materials, would be destroyed, owing to the
quantity of oxygen and hydrogen contained in the gas.
And, lastly, the regulator consists of a pressure spring g of peculiar
make, and employed for the purpose of constant regulation. The spring
is made of two layers of watch spring steel, its bearings being at h, and
it is in connection with the lever e. By means of its proportionately
great length it is in a position to fulfil the functions hereafter described.
A direct pressure weight would increase the vibrations caused by the.
driving of the train so much as to extinguish the gas lights instantly.

page_text: T
The apparatus for the regulation of the pressure on gas, when com-
pressed gas is employed, has to fulfil the following functions:-The
compressed gas passes the dust receptacle, goes through the channel of
the regulating place c against the new and peculiar regulating cone d,
then through the 6 passages of the conductor of the regulating cone d,
(see the detail views on Sheet I., and fills the cast iron vessel a
through the pressure of the gas streaming in the leather membrane f
and with it the lever connection e and the regulating cone d are raised,
and the spring 9 effects by means of its tension the pressure necessary
for burning, and regulates the difference of pressure at the same time
arising from the motion of the carriages.
Sheet III. shews a part of a railway carriage lighted by gas according
to this Invention. The oil gas being compressed to about 6 to 8 atmo-
spheres is kept in a reservoir A; or, if considered necessary, there can
be two reservoirs affixed to the bottom of the carriage, and which can be
filled after a lapse of from 24 to 36 hours by means of a suitable com-
pression pump at those railway stations where the gas is manufactured.
The gas goes from this reservoir by pressure to the above described
regulator, which is likewise affixed to the bottom of the carriage, as seen
at B, and issuing from the latter with the usual burning pressure it is
conducted by pipes fixed to the sides and top of the carriage direct to
the several burners.
In witness whereof, I, the said John Clayton Mewburn, have here-
unto set my hand and seal, this Twenty-second day of January,
One thousand eight hundred and seventy-four.