IMPROVEMENTS
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by the said Isaac Thomas at the Office
of the Commissioners of Patents on the 30th March 1883.
ISAAC THOMAS, of Aberdare in the county of Glamorgan
FIRE AND OTHER ALARMS
"
"IMPROVEMENTS IN
In carrying out this invention I prefer to employ a bell hung on a spring and
held by a detent to is attached a cord or equivalent which may be chemically or
otherwise prepared or formed of materials which ignite readily. This cord is
stretched along the walls across the floor or otherwise placed in the room or other
place from which the warning is to be sent in case of fire.' When a fire arises the
cord ignites directly and breaks and releases the detent which allows the bell to
slip and commence ringing thus warning the persons near it that something is
wrong. The bell may be placed in any desired room or locality and bell cranks &c
may be used for carrying the cord round corners and so forth as needed.
Several cords may be arranged to control one bell so that should a fire occur in
any room in which a cord is placed an alarm may be speedily given.
3
I do not confine myself to a bell only as of course the cords could be used to
start the alarm of a 'clock or other alarm device as will be readily understood.
The cords may be placed across doors, windows, staircases. &c and arranged so as
'to give the alarm-in case of burglars and the like One strong cord will do to rún
round several rooms or the whole house if required, while a slight cord which is
placed round the skirting boards, up and round the doors and architraves with small
leading pullies and kept tight with a spring or equivalent will quickly ignite with
any fire or flaine, and break and start the bell or other alarm.
It may be made with safety fuze and placed across the room if necessary.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Isaac Thomas in the Great Seal Patent Office on the 27th September
1883.
ISAAC THOMAS of Aberdare in the County of Glamorgan
FIRE AND OTHER ALARMS
"
"IMPROVEMENTS IN
In carrying out this invention I prefer to employ a bell hung on a spring and
held by a detent to which is attached a cord or equivalent which may be chemically
or otherwise prepared or formed of materials which ignite readily-this cord is
stretched along the walls, across the floor, or otherwise placed in the room or
other place from which the warning is to be sent in case of fire. When a fire
arises the cord ignites directly and breaks and releases the detent which allows
the bell to slip and commence ringing, thus warning the persons near it that
something is wrong-the bell may be placed in any desired room or locality, and
bell cranks & may be used for carrying the cord round corners and so forth as
'needed.
Several cords may be arranged to control one bell so that should a fire occur in
any room in which a cord is placed an alarm may be speedily given. I do not
confine myself to a bell only as of course the cords could be used to start the alarm
of a clock or other alarm device as will be readily understood.
The cords may be placed across doors, windows, staircases & and arranged so as
to give the alarm in case of burglars and the like One strong cord will do to run
round several rooms or the whole house if required, while a slight cord which is
placed round the skirting boards up and round the doors and architraves with
small leading pulleys and kept tight with a spring or equivalent will quickly ignite
with any fire or flame, and break and start the bell or other alarm. It may be made
with safety fuse and placed across the room if necessary.
In the accompanying drawings Figure 1 is a sectional elevation of a building
showing how the cord runs, figure 2 is an inverted plan of a ceiling shewing the
cord carried several times across it. Figure 3 shows what I call the "Burglar
Blind" for securing windows, doors & and Figures 4 to 8 are details of construction.
Referring to Figure it will be seen that the cord A commences at the signal
bell or other alarm B and is stretched in the direction indicated by the arrows,
'carried round pulleys or bell cranks C (shewn in detail in Figures 4 and 5) through
, as many rooms as is found desirable or practicable and then secured at D, so that
the cord remains sufficiently tightly stretched. For this purpose the terminal
fastening at D may with advantage be formed of a screwed rod and suitable
"bracket, the cord being secured to a loop at one end of the rod, and a thumb screw
serving to tighten it by An equivalent device may be used such for instance as
having one of the pulleys adjustable so as to take up the slack of the cord.
In Figure 1 two cords and two separate alarms are shewn in the one building,
but more or less may be employed, and more than one cord may be in connection
with the same alarm.
In Figure 2 the cord A terminates at D after passing round the pulleys C and
crossing the ceiling several times; the alarm is in some other part of the building.
The "Burglar Blind" Figure 3 consists of a roller E in which are pulleys C and
a bar F also fitted with pulleys C, and a rod and thumbscrew G to tighten the
"blind" with when set for the night or when required. The cord terminates at D
passes round the pulleys C as shown and away to the alarm wherever required.
When not required the "blind" is rolled up the cords wrapping round the roller.
When wanted for use it is unwound like an ordinary blind and strained tight at G,

page_text: so that when one of the cords is cut the signal will be given in the same way as
the rest.
If any part of this cord A becomes severed as by fire or knife the bell is
released or in the case of an electric bell, contact is made-and the signal given-
It is preferred to make the cord of inflammable or readily igniteable material so
that at the least flame it may burn through and give the alarm
Figures 4 and 5 show how the pulleys and bell cranks may be fitted to the
corners.
Figure 6 shows an ordinary house-bell in which the lever H is pulled over by
the cord A. and upon that being severed the bell flies back giving the alarm.
Figure 7 shows the adaptation for an electric bell. The lever I is pivotted at K
the spring L giving it a tendency to cause its upper end to lean over and make
contact with the contact point M: contact however is prevented by, the cord A
which pulls the lever away from M as shewn in the drawing. One wire is
connected to the lower end of the lever as shewn and the other being joined to the
contact point M. When the cord is severed the lever flies over and makes contact
with M and the bell rings as will be well understood.
In Figure 8 a simple fixed bell is used with a spring hammer which flies forward
and strikes the bell when the cord is severed.
Having now described my invention and the method of performing the same I
wish it to be understood that what I claim and desire to protect under the
hereinbefore in part recited Letters Patent is :-
First. As a means of giving an alarm of fire, burglars or the like, a stretched
cord which when severed by fire or otherwise, ceases to restrain the alarm apparatus
and permits a signal to be given substantially as set forth and shewn in the
accompanying drawings.
Second The spring contact lever I in combination with the stretched cord A and
contact point M operating substantially as described and shewn in Figure 7 of the
accompanying drawings.
:-
Third The combination of the roller E, bar F, straining attachment G pulleys C
and cord A, the whole constructed and operating substantially as and for the purposes
set forth and shewn in Figure 3 of the accompanying drawings.
In witness whereof I the said Isaac Thomas have hereunto set my hand and
seal this twentieth day of September in the year of our Lord One thousand eight
hundred and eighty three.
ISAAC THOMAS
(L.S.J