AN IMPROVED APPARATUS FOR INDICATING THE EXISTENCE OF INFLAMMABLE AIR OR FIRE DAMP' IN MINES
Year: 1879

page_text: LETTERS PATENT to Guido Körner, Studiosus rerum Montanarum, of the City
of Freiberg, Kingdom of Saxony, German Empire, for the Invention of "AN
IMPROVED APPARATUS FOR INDICATING THE EXISTENCE OF INFLAMMABLE AIR
OR FIRE DAMP' IN MINES.”
Sealed the 12th August 1879, and dated the 13th February 1879.
PROVISIONAL SPECIFICATION left by the said Guido Körner at the Office
of the Commissioners of Patents on the 13th February 1879.
GUIDO KÖRNER, Studiosus rerum Montanarum, of the City of Freiberg, Kingdom
of Saxony, German Empire. "AN IMPROVED APPARATUS FOR INDICATING THE
EXISTENCE OF IMFLAMMABLE AIR OR "FIRE DAMP" IN MINES."
This Invention relates to improved apparatus for automatically indicating the
presence of foul air or fire-damp in mines, and is based upon the discovery that
platinum-black possesses the peculiar property of causing light carburetted
hydrogen (CH), which is the chief constituent of fire damp, to condense on its
surface, even when but a small amount of this gas is present in the atmospheric air,
and in this close contact to cause a combustion of the light carburetted hydrogen.
I make use of this hitherto unknown property of platinum-black for the purpose of
my said Invention in the following manner, that is to say: I provide a box partly
made of open wire-work and place within the same a thermometer-tube filled with
mercury and open at the top, into the bulb of which thermometer a piece of
platinum wire has been inserted while the glass was in a liquid state, the said wire
being connected to a conducting-wire by means of a set-screw. The glass bulb of
the thermometer is surrounded by a carbon-cell which is filled with platinum-black.
When economy is an object I may employ a mixture of platinum-black and
asbestos instead of pure platinum-black. Two platinum wires of different lengths
dip down into the top part of the said glass tube, the longer of these leads direct to
an electric-conducting-wire, but the shorter one leads first through an electric
bell-apparatus placed near to an indicator and then to the conducting wire. Several
of these indicators are placed in the mine. If fire damp is present it will pass
Die C

page_text: through the wire-netting of the said box, penetrate with a mixture of air through
the said carbon-cell, and lastly make its way to the platinum-black. The latter
effects a slow combustion of the same, and the mercury rising in the glass tube
-through-the-action-of-the-heat-thus-developed touches first the aforesaid longer
platinum-wire. Thus a conducting-connection is established between the point of
platinum in the bulb and the point of the longer of the two platinum wires in the
-top-of-the-tube, and it is thus made possible to signal the fire-damp to the top of
the mine by means of an electric current. If now by the development of heat,
which depends upon the quantity_of_carburetted hydrogen mixed with the air, the
mercury should rise to such a height that it touches the second platinum wire,
namely, the shorter one, then, the current will operate a pit-alarum which is con-
.nected with this wire close by the indicator.
By means of this foul air indicator the safety arrangements in the mine can be
effected in different ways. The first requirement appears to be that persons in
the office connected with the mine should be made aware of the presence of the fire-
damp, in order that suitable precautions may be taken for the prevention of
accidents. I therefore place a signalling apparatus in the said office for this
purpose, and an electric signal receiving or collecting apparatus in the mine, which
receiving apparatus is made on the principle of the so called "Siemens" needle-
apparatus. The needle on the said receiving or collecting apparatus in the mine
guides a small wheel in a circular path on which are arranged conductors insulated
from each other. Each of these conductors on the circular path is connected with
the conducting wire of each indicator.
The current is made to go as follows, namely:-From the negative pole of the
battery to an electro-magnet in the said signalling apparatus, whence it passes to
and through the said receiving or collecting apparatus to the return-wire and to
the positive pole of the battery. This is when only one receiving or collecting
apparatus is used in the mine, but if several receiving apparatuses are used, then
the current will be led through all of them in the same manner before it reaches
the return-wire which conveys it to the positive pole of the battery. The electro
magnet in each apparatus will attract a movable piece or anchor at the same tine.
By this means a bridge-piece provided in cach apparatus will be pressed upon a
contact-screw, the current will be broken and a ratchet-wheel will be turned one
tooth further by means of a spring. By the contact between the said bridge-piece
and the said screw, and while the said ratchet wheel is advanced one tooth, the
current will be led through various parts of the apparatuses to the needle of the
receiving or collecting apparatus, the said small wheel, and to the indicator.
If the current is closed in this indicator through the mercury then it passes on
through indicator Number 3 to the return wire and to the positive pole of the
battery. The electro magnet in this circuit will consequently attract its anchor,
the alarum is sounded, and the needle indicates in the office by which indicator
the current has been closed, that is to say, at what part the fire-damp is
present.
By the return movement of a lever in the receiving or collecting apparatus
through a spring the aforesaid ratchet wheel, and consequently the needle of each
apparatus, will be advanced an equal distance, the bridge-piece will be pushed back
and the alternate course of the current will be re-established. If none of the
indicators are in action then the current led by the second route will nowhere have
its circuit completed, and the electro-magnet and the alarum in No. 1 apparatus
will consequently not be brought into operation.
If the smaller platinum wire in the indicator is by means of the mercury brought
into the circuit, then the current goes by this branch-line to the electro-magnet
connected with the alarum in the mine near the indicator, and the bell is sounded,
warning the workmen of the danger. The signal is also made observable in the
office because the current in the longer wire will also be interrupted by the inter-
mittent action of the alarum in the mine, and consequently the anchor of the
electro-magnet in the signalling apparatus in the office will be actuated in rapid

page_text: succession. The alarum which otherwise only sounds once or twice is now sounded
in rapid succession.
If it should appear to be advisable to have several receiving or collecting
apparatuses in the mine, then they may all be brought into connection by the same
current from the office.
There is still one requirement left to be fulfilled which is that the conducting
parts of the different circular paths should be so arranged that the small pointer
wheel of any one of the pointers should only stand on one of the conducting parts
of the circle of any one indicator, while the remaining ones are moving on the
intermediate spaces. In such a case one of the receiving or collecting apparatuses
is to be so arranged that the current may be led through the small wheel on
the pointer and to the receiving-apparatus No. 3. Here it makes its way through
the various parts of the apparatus and endeavours to find an indicator to make a
connection with the return wire. In this manner three or more receiving or
collecting apparatuses may be joined with one wire-circuit.
If it should be required only to have the alarum signal in the mine, then a
battery has to be placed there and a main-wire connection led through the mine, to
which are joined the conducting wires from the indicators. The current will then
only find a circuit completed in the indicator which is in operation, and only that
alarum will sound. The indicator would then only require the said platinum-wire
first mentioned, namely, the one which passes into the bulb of the thermometer and
the shorter of the two other wires.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Guido Körner in the Great Seal Patent Office on the 13th
August-1879:
GUIDO KÖRNER, Studiosus rerum Montanarum, of the City of Freiberg, Kingdom
of Saxony, German Empire. "AN IMPROVED APPARATUS FOR INDICATING THE
EXISTENCE_OF_INFLAMMABLE AIR OR FIRE DAMP IN MINES."
This-Invention-has-for-its-object--an-improved-apparatus for indicating the
existence of inflammable air or fire damp-in-mines, which-Invention-is-based-upon-
the following observations
Platinum black possesses the quality of condensing on its surface light carburetted
hydrogen gas (marsh gas) CH,, even if only a small part of this gas is contained
in the atmosphere. In this intimate contact platinum black effects a combustion of
the light carburetted oxygen gas. This property of platinum black which was
until lately unknown serves by the use of my improved apparatus to indicate the
presence of fire damp in the manner hereinafter described, and illustrated by the
accompanying Drawings.
And in order that my said Invention may be better understood I will now
with the aid of such Drawings proceed more particularly to describe and ascertain
the same.
Figure 1 of such Drawings shews a view in external elevation of my improved
indicating apparatus; Figure 2 shews a view in longitudinal section thereof;
Figure 3 is a view in cross section taken at the line A, A¹, Figure 1; and Figure 4
is also a view in cross section taken at the line B, B1, Figure 2.
In order to carry out my Invention I proceed as follows:-In a wooden box, the
bottom of which is open and covered only with a net of wire gauze, I place a
thermometer filled with mercury the glass of which is open at the upper end, while
into the ball of the thermometer a platinum wire is melted leading by means of a
hold screw a to a telegraph wire. The glass is covered with a coal cell b formed of
pulverized coal which is moistened with syrupy water and roasted on a soft fire.
This coal cell is filled with platinum black. In the upper end of the glass tube
are hanging low platinum wires of different lengths m and n. The longer wire m
leads direct to an electric wire, the shorter one n leads to an electric alarum bell
which hangs next to the indicator and thence it leads to the electric wire. This
indicator is put in position in different parts of the mine. As soon as fire damp
appears it penetrates through the wire gauze into the box and forces its way through
the pores of the coal cell, and in this manner comes in contact with the platinum
black. This causes a slow combustion of the inflammable gases. In consequence
of the heat so generated the mercury in the glass rises and touches the longer wire m.
In this way connection is formed between the platinum wires m and l, and in this
manner the presence of fire damp can be signalled in the office of the mine above
ground-by-means-of-a-telegraphic-wire.
When the mercury in consequence of a large amount of heat (depending upon
the quantity of the carburetted hydrogen or inarsh gas mixed with the air in the
mines), has risen to such a height that the smaller wire n is touched, also the
alarum clock which is in connection with such wire n will get into action, conse-
quently the mine can be managed with security by the use of the indicator in
various ways.
At first it is necessary to inform the officials in the office above ground of the
presence of fire damp in the mine in order to prevent accidents. Therefore an
electric signal apparatus is fixed in the office; Figure VII. of the accompanying
Drawings represents in outline the general disposition of the electrical apparatus,
No. I. represents the electric signal apparatus in the office, and Nos. 2 and 3 the
signal collecting apparatus in the mines joined with the various indicators of fire

page_text: damp. The construction of this apparatus, which is illustrated at Figures 5
and 6, is based upon the well known telegraphic indicator apparatus of Messieurs
Siemens.
The indicator Z" of the collecting apparatus in the mines leads a small wheel d
upon a circle which is formed by conductors isolated from one another.
The con-
ducting wire of each indicator of fire damp is connected with one conductor of this
circle road e¹¹, (see Figure VII., Nos. 2 and 3.
The electrical current circulates as follows:-From the pole K of the battery over
D¹, S¹, P¹, E¹, L, No. 1, Figure 7, to No. 2, Figure 7, which is placed in the mine,
thence over E, D", S", P", L", to No. 3 over E, D, S, P₁, to the retroconduc-
tion and to the zinc pole Z. The electrical magnets E', E", E, begin to draw
their anchors (see Figures V. and VI., by which the bridge S₁, S, S, is pressed
on the contact screw Q¹, resp. Q", Q, the current is interrupted between S and P¹,
and the balance wheel c¹ is turned by the spring f" at one cog. By the contact of
the little bridge 8" with the screw Q' resp. Q, Q111, the current is conducted, the
balance wheel cl advancing one cog in the following direction (see annexed
Figure VII.).
From K to No. 1, D¹, S', Q', F¹, L', to No. 2, E", D", S", Q", M", Z", in the
metallic wheel d₁ to the indicator of fire damp I³. The current being closed in
this indicator by the mercury goes through I³ to the retro-conducting and to the
zinc pole Z.
The electrical magnet F (see Figure VII., No. 1) being the circumclosed current
effects the closing of a local battery with the alarum signal in the office. The
electrical magnet E and F continue drawing in their anchors till the official
attendant interrupts the current after having taken notice of the alarum signal.
The indicator Z' which advances simultaneously with Z" and Z indicates to
the.official through which apparatus the current is closed, and at the same time
reveals this as the locality where fire damp exists.
If the second platinum tag n of the indicator of inflammable air is in contact
with the mercury in the closed current the current will pass through this branch
conduction around the electrical magnet of the alarum clock next to the indicator,
the clock rings, and informs the workmen of the danger.
If it is advisable to place in the mine several conducting apparatus (as supposed
in Figure VII.) the arrangement is to be made so as to dispose of the conducting
parts of the different circular roads ell, 71, in such manner that the wheel d of only
one indicator Z" is placed on a circle part leading to an apparatus indicating the
fire damp, the other wheel d moving on an intermediate part. For that case
the one collecting apparatus is disposed, as shewn by Figures V. and VI., and
Figure VII., No. 2, so that the current going over Q1, M, Z", may be conducted
by the little wheel du to e"; L", E, M, ell, trying to find in any
indicator the connection with the retro conduction. In this way three or more
collecting apparatus may be joined in one wire.
If it is desired to give only the alarum signal in the mine a battery is placed
there, and the principal wire leads the current to the several indicators in the
mine. The current is closed only in the operating indicators and only this clock-
work will ring. In this case the indicator needs only the low platinum wires
and n.
It appears then from the above description and the accompanying Drawings that
my Invention is new and original in the following points,-
1°. I have discovered the fact that carburetted hydrogen gas CH,, under the
influence of platinum black (platinum mohr) burns slowly, and on that fact I base
my apparatus for indicating fire damp as described and designed, advancing this
fact as new and original.
2°. The transformation of the indicating apparatus of Messieurs Siemens to a self
working collecting apparatus for electric signals, in which I regard as new and
original the construction of the indicator, and the course of the wheel by which the

page_text: conduction of the current is effected in the manner above described and represented
by the annexed Figures V., VI., and VII., Nos. 2 and 3.
:
3°. The arrangement as described and represented in order to signalize by means
of platinum black (platinum mohr) and an electric conductor the existence and the
locality of fire damp-to-the-office-of-the mine, and to inform the workmen of the
danger.
Having thus particularly described and ascertained the nature of my said Inven-
tion, and the manner of carrying the same into effect,-I-would have-it-understood
that I do not confine myself to the precise details hereinbefore set forth; what-I
consider.as.novel and desire to secure by the hereinbefore in part-recited Letters
Patent is,―
1°. My improved apparatus for indicating the presence of inflammable air or
fire damp in mines, substantially as hereinbefore described and illustrated.
2°. The automatic electric signal collecting apparatus, substantially as herein-
before described and illustrated.
3°. The arrangement for indicating the presence of fire damp based upon the
influence of carburetted hydrogen gas upon platinum black, substantially as herein-
before described and illustrated.
In witness whereof, I, the said Guido Körner, have hereunto set my hand
and seal, this Thirteenth day of August, in the year of our Lord One
thousand eight hundred and seventy nine.
GUIDO KORNER. (L.S.)