IMPROVEMENTS IN GAS PYROMETERS, WHICH MAY ALSO BE EMPLOYED AS THERMOMETERS
Year: 1866

page_text: ETTERS PATENT to Baldwin Fulford Weatherdon, of 77, Chancery
Lane, in the County of Middlesex, Civil Engineer and Patent Agent,
for the Invention of "IMPROVEMENTS IN GAS PYROMETERS, WHICH MAY ALSO
BE EMPLOYED AS THERMOMETERS."-A communication from abroad by
Joseph Jean Marie Durand, of the Firm of Charles Leroy and Durand, of
25, Route de Fontainebleau, Gentilly, (Seine,) in the Empire of France,
Candle Manufacturers, and Celestin Pichoin, of 100, Route d'Italie
Paris, in the Empire of France, Chemist.
Scaled the 9th November 1866, and dated the 26th May 1866.
PROVISIONAL SPECIFICATION left by the said Baldwin Fulford Weather-
don at the Office of the Commissioners of Patents, with his l'etition, on
the 26th May 1866.
1, BALDWIN FULFORD WEATHERDON, of 77, Chancery Lane, in the County
of Middlesex, Civil Engineer and Patent Agent, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN GAS PYROMETERS, WHICH MAY ALSO BE
EMPLOYED AS THERMOMETERS," (a communication from abroad by Joseph Jean
Marie Durand, of the Firm of Charles Leroy and Durand, of 25, Route de
Fontainebleau, Gentilly, (Seine.) in the Empire of France, Candle Manu-
facturers, and Celestiu Pichoin, of 100, Route d'Italie, Paris, in the Empire
of France, Chemist,) to be as follows, (that is to say):
This Invention has for ts object the measuring and ascertaining of the

page_text: temperature and elasticity or tension of any gas contained in a closed vessel,
and consists of an instrument composed of glass tubes, shaped in like manner
to a barometer, and furnished with a vessel formed of platinum or otherwise,
capable of containing about a quart of nitrogen, the dilation of which gas is
caused to exercise its pressure on mercury within a glass bulb or ball, so that
the degrees of heat or otherwise can be readily ascertained and marked down
through the medium of suitable graduations upon the glass, whereby great
accuracy combined with simplicity is obtained.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Baldwin Fulford Weatherdonin the Great Sea! Patent Office
on the 23rd November 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, BALDWIN
FULFORD WEATHERDON, of 77, Chancery Lane, in the County of Middlesex,
Civil Engineer and Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-sixth day of May, in the year of our Lord
One thousand eight hundred and sixty-six, in the twenty-ninth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Baldwin Fulford Weatherdon, Her special licence that I, the said
Baldwin Fulford Weatherdon, my executors, administrators, and assigns, or
such others as I, the said Baldwin Fulford Weatherdon, 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 "IMPROVEMENTS IN GAS PYROMETERS WHICH MAY ALSO BE
EMPLOYED AS THERMOMETERS," (being a communication from abroad,) upon the
condition (amongst others) that I, the said Baldwin Fulford Weatherdon,
my executors or administrators, by an iustrnment 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 1,the said Baldwin Fulford Weatherdon, do hereby
declare the nature of my said Invention, and in what manner the same is to be

page_text: performed, to be particularly described and ascertained in and by the following
statement and the Drawings therein referred to (that is to say):-
This Invention has for its object the employment of the variations of
volume developed in gaseous or other bodies resulting from the various tem-
peratures of the matter in which the said body is placed, whereby physical and
mechanical effects are produced calculated to maintain an equal temperature
in the said matter, and consists of a mercury thermometer, gas pyrometer, or
otherwise, having two branches or tubes springing vertically from the bulb,
in each of which said tubes platinum wires surmounted with silk, thread, or
other insulating matter are so arranged in connection with electric piles aud
magnetic coils moving in conjunction with supply and discharge water taps,
valves, air passages, or otherwise, as to admit of the said regulation being
uniformly and accurately maintained.
But in order that my said Invention may be more fully understood and
readily carried into effect, I now proceed to describe the same by the aid of
the accompanying Drawings, reference being had to the letters and figures
thereon marked (that is to say):-
Fig. 1 represents a side elevation of the apparatus partly in perspective,
shewing the construction thereof and mode of working the same; Fig. 2,
enlarged detail views of the thermometer tubes, shewing the graduations
thereon; Fig. 3, a front view of a gas pyrometer upon my improved system;
Fig. 4, enlarged view of the socket plug and upper portion of one of the tubes
in Fig. 3; Fig. 5, a vertical side view of a pyrometer which may be used as
a thermometer; and Fig. 6, a side view of a weighing pyrometer partly in
section. In each Figure the same letters of reference denote similar corres-
ponding parts.
A, A, bulb of the thermometer; B and B¹, graduated tubular branches as
seen at Fig. 2 open at the upper ends; C, C, mercury; D and D', insulated
platinum wires placed within the tubular branch B, communicating with the
electric pile E, E, and electro-magnets F, F; G, G, horse-shoe hammer
magnets for putting the apparatus in motion; H, H, copper blocks on which
the hammer falls when not attracted; I, I, levers worked by the magnetic
hammers aforesaid upon the stands or bearings J and J; K, K, cords for
communicating motion to the water valves L, L; M and M, platinum wires
placed within the branch B', in communication with the electric piles N and
N', and the electro-magnets () and O'; P, P, elastic blade attached to Q of
the electro-magnet O; R, R, spring against which the elastic blade reacts;
S, S, tank charged with water; T, T, tank for supplying the same; U, U,
water line; V, V, float or water guage. W, W, ratchet wheel and axle gear

page_text: for opening or shutting the valve X or otherwise through the rise and fall of
the float V, pulley cords and counterbalance weight Y and Y; Z, Z, pulleys
on which the cords work.
In Fig. 3, a, a, is a vessel charged with dry nitrogen or azote having a
tube b, b, projecting therefrom communicating with a syphon tube b' and b²,
charged with mercury c, c, into which the insulated conductors a, e, and f, g,
are placed; h, h, socket plug or cap for securing the said conducting wires
within the tubes.
In Fig. 6, i, i, weighing cylinder; jand j¹, piston rod and weight; k, k
gas chamber; 1, 1, passage through which the expanding gas passes to th c
weighing cylinder.
The action is as follows:-By placing the bulb of the thermometer A,Fig.1,
within the heated fluid body or matter to be regulated, the mercury c is
caused to ascend within the tubes B and B', and by touching the ends of the
wires D and D', M and M', arranged to any suitable graduations within the
said tubes, the electric current is put in motion and the magnetic hammers G
attracted or repelled so as to raise the levers I, and thereby actuate the valves
in the tanks for the supply or discharge of the water to or from the same,
whereby the ratchet wheel is put in motion, and the damper opened or closed
for the purpose of increasing or diminishing the heat beneath the matter
to be regulated, by which an uniformity of temperature in the same is
maintained.
In conclusion to the foregoing description I would here note that in con-
nection with the above system common thermometers may be applied to the
self-regulating apparatus in like manner to the above, and formed wholly or
partly of glass, china, or platinum as may be found suitable.
And I would further note that I also employ dry nitrogen or azote, within
platinum vessels before described as an expanding medium for bringing the
mercury in contact with the wires before mentioned in lieu of glass and
mercury, being less subject to fracture or otherwise by greater or less
heat.
And I would again further note that the above principle with modifications
is also applicable to other purposes than those above enumerated such as for
clockwork, alarums, or otherwise, employing in like manner the mercury or
gas bulb "which is termed the monitor," in connection with the electric
piles and maguets "termed the messenger," and the hydraulic system
"termed the motor."
Having now fully described and ascertained the nature of this my said
Invention, and the manner in which the same is to be performed and carried

page_text: into effect I would have it clearly understood that I do not intend to confine
myself to the precise details herein-before described as the same may be
otherwise varied without departing from the general principle of this my said
Invention, nor do I claim as new and of the said Invention the exclusive use
of the several parts, combinations, and processes herein-before described,
except when the same are employed in and for the purposes of my said
Invention which I hereby declare to consist,-
Firstly, in using the variations of volume developed in a body through the
various temperatures of the matter in which the said body is placed, whereby
an uniform and equal temperature in the said matter is maintained.
Secondly, in the combination and employment of thermo-pyrometers with
electric apparatus.
Thirdly, in the electro-magnetic power or messenger for actuating the
inotor through the medium of levers.
And, fourthly,inthe combination and mode of employing clockwork, alarums,
or other appliances in connection with the electric self-regulating system in
the manner and for the purposes herein-before set forth and described.
In witness whereof, I, the said Baldwin Fulford Weatherdon, have here-
uuto set my hand and seal, this Twenty-third day of November, in
the year of our Lord One thousand eight hundred and sixty-six.
B. F. WEATHERDUN. (L.S.)
Witness,
R. H. P. Cooke,
Clerk to Messrs. Weatherdon & Co.,
77, Chancery Lane.