IMPROVEMENTS IN MEANS AND APPARATUS FOR DENOTING AND INDICATING ANY INCREASE IN PROVISIONAL SPECIFICATIONREA IN THE TEMPERATURE OF COAL AND OTHER SIMILAR CARGOES
Year: 1883

page_text: LETTERS PATENT to Thomas Rowan of Palace Chambers, in the city of
Westminster, Consulting Engineer for an Invention of "IMPROVEMENTS IN
MEANS AND APPARATUS FOR DENOTING AND INDICATING ANY INCREASE IN
PROVISIONAL SPECIFICATION left by the said Thomas Rowan at the Office
of the Commissioners of Patents on the 2nd January 1883.
THOMAS ROWAN, of Palace Chambers, in the city of Westminster, Consulting
Engineer "IMPROVEMENTS IN MEANS AND APPARATUS FOR DENOTING AND
INDICATING ANY INCREASE IN THE TEMPERATURE OF COAL AND OTHER SIMILAR
CARGOES
"
This invention relates to improved means and apparatus for signalling and
indicating the commencement and locality of any dangerous rise in temperaturo in
coal and other cargoes liable to heat or become ignited.
=
A suitable arrangement for carrying out my invention is as follows:-
In the holds of the vessels, arranged throughout the cargo and at different levels
therein, I provide a series of suitably perforated tubes leading to the upper surfaco
of the cargo; or instead of simple tubes I employ suitable air abstractors. In
the said tubes, or in the said air abstractors, I place thermometers so arranged that
on the temperature rising the mercury on reaching any regulated point will form
electrical contact with suitably placed wires in communication with electric bells
and indicating mechanism situated in any desired position in the ship such as in
the engineer's or captain's cabins or both.
By this arrangement, if the temperature of any part of the cargo rises to the
point which is required to be indicated, not only will this be signalled at the very
moment when such rise in temperature takes place but the particular thermometer
causing the signal will be pointed out by the fall of the corresponding indicator and
consequently the locality in the cargo where the rise of temperature has taken
place.
In this manner the absolute starting of such an action as spontaneous combus-
tion in coal and other cargoes will be unmistakably brought to notice and ample
time afforded to tako the necessary means for saving both ship and cargo.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent and
of an Order of the Lord Chancellor filed by the said Thomas Rowan in the
Great Seal Patent Office on the 5th July 1883.
THOMAS ROWAN of Palace Chambers in the city of Westminster, Consulting
Engineer "IMPROVEMENTS IN MEANS AND APPARATUS FOR DENOTING AND
INDICATING ANY INCREASE IN THE TEMPERATURE OF COAL AND OTHER SIMILAR
CARGOES
"
This invention relates to improved means and apparatus for signalling and
indicating the commencement and locality of any dangerous rise in temperature in
coal and other cargoes liable to heat or become ignited.
In the annexed drawing figure 1 is a diagram which is given merely to illustrate
a suitable arrangement for carrying out my invention.
In the holds of the vessel a, arranged throughout the cargo and at different
levels therein, I provide a series of suitably perforated tubes or chambers b, c, d,
leading to the upper surface of the cargo and to the upper deck e, where they may
be provided with air abstractors or cowls; or instead of simple tubes or chambers
as shewn I employ suitable air abstractors. In the said tubes or chambers b, c, d,
(or in the said air abstractors) I place electrical thermometers f, (preferably of the
construction hereinafter described) so arranged that on the temperature rising to
any regulated point electrical contact will be formed with suitably placed wires g,g,
in communication with electric bells and indicating mechanism h, situated in any
desired position in the ship such as in the captain's cabin A, or in the engineer's
cabin or in both.
By this arrangement if the temperature of any part of the cargo rises to the
point which is required to be indicated, not only will this be signalled at the very
moment when such rise in temperature takes place but the particular thermometer
causing the signal will be pointed out by the fall of the corresponding indicator
and consequently the locality in the cargo where the rise of temperature has taken
place.
In this manner the absolute starting of such an action as spontaneous combustion
in coal and other cargoes will be unmistakably brought to notice and the cargo
being thus, so to speak, subdivided presents the means of controlling all tho
ultimate stages of spontaneous combustion of the cargo as the heated products of
incipient combustion can be drawn off from the locality of their production and
would thus be prevented from lodging amongst the body of the coal, where they
might induce or excite action of a similar nature. Heat, therefore, would not be
retained and accumulated in the cargo and, consequently, those elevations of
temperature required for inflamınability would not be reached.
With the means of thus ascertaining from different parts of the cargo what was
taking place, the captain of the ship would have ample time to prevent the action
resulting in any serious catastrophe. Under any circumstances the loss of the
vessel could always be prevented, and probably the saving of all but an incon-
siderable portion of the coal be also effected.
It is obvious that this invention is also suitable for other cargoes than coal.
The thermometers which I find it advantageous to use for the purposes of my
invention are shewn in figures 2, 2, 3, and 4 of the accompanying drawing.
The thermometer shewn in figure 2, consists of a tube a, of metal, glass, earthen-
ware or other suitable material the ends of which are closed by plugs b, b¹, of any
suitable insulating material through one of which plugs b, the shank of the terminal
screw d, is brought ending in a contact piece or stud f. Through the other plug b',

page_text: the end of the spiral c, passes ending in the terminal screw d¹. The spiral c,
consists of two metals of a different ratio of expansion under the influence of heat
such as antimony and zinc soldered together, the metal of least expansion being
placed uppermost as shewn in the enlarged view figure 2*, with the result that on
the temperature rising the spiral c, is. lengthened and makes contact with the
stud f, thereby completing the circuit in connection with the bell and indicator.
Figure 3, is a modification of the arrangement shewn in figure 2, the chief
difference being that the spiral c, is bent back upon itself in the manner shewn in
the drawing thereby allowing of the two terminals d, d¹, being brought through
the same insulating block or plug b.
In another arrangement shewn in figure 4, I dispense with the double metal
spiral using instead a cylindrical coil c, of any suitable single metal such as iron
the lower end of which passes through the insulating plug b', to the terminal
screw d, the other end g, being turned up in the manner shewn in the drawing.
On any increase of temperature the tendency of the coil c, is to uncoil itself and
in so doing the turned up end g, will be brought into contact with a radial arm
or contact piece, which is attached to the shank of the terminal screw d.
It will be obvious that the thermometers can be set or adjusted so as to make
contact and sound the alarm at any desired temperature.
Having thus described my invention and the manner of performing the same
what I claim is :-
Firstly. The method herein described of ascertaining indicating and signalling
the commencement and locality of any dangerous rise in temperature in coal and
other cargoes, by the use of tubes, chambers or abstractors provided with suitable
thermometers in combination with indicating and signalling apparatus the whole
arranged and operating substantially in the manner herein before described.
Secondly. The use for the purpose herein described of thermometers constructed
arranged and operating substantially as hereinbefore described and represented in
figures 2, 2ª, 3 and 4, of the accompanying drawing.
In Witness whereof I the said Thomas Rowan have hereto set my hand and
seal this fifth day of July in the year of our Lord one thousand eight hundred
and eighty threc
THOMAS ROWAN (L.S.)