IMPROVEMENTS RELATING TO HAND-GRENADES FOR EXTINGUISHING FIRE
Year: 1885

page_text: We, JAMES SINCLAIR, of 104 Leadenhall Street, in the City of London, Mercbant,
and JOHN COTTRELL, of the Royal Institution of Great Britain, Albemarle Street,
Piccadilly, in the County of Middlesex, Physicist do hereby declare the nature of our
invention for "IMPROVEMENTS RELATING TO HAND-GRENADES FOR EXTINGUISHING
FIRE" and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
Our invention relates to that class of devices known as hand-grenades for
extinguishing fire.
The hand-grenades heretofore made for this purpose consist of glass bottles or
vessels which contain liquid and gas under pressure. In order to enable these
vessels to withstand the internal pressure of the gas, it is necessary to make them
so thick that the breakage of the same by throwing them into the fire is rendered
difficult, especially if they happen to come in contact with a yielding substance.
To overcome this difficulty, hand-grenades have been heretofore designed, which
consist of two or more separate glass vessels placed together and provided with
suitable means for retaining them in position "relatively to each other, the object
being to provide for the breakage of one or more of the said vessels by mutual
impact, that is to say, by the force exerted upon one vessel by another when the
hand-grenade is thrown into the fire. But, as each of these vessels contains liquid
and gas under pressure, the material of which it is composed must be of sufficient
thickness to withstand the internal pressure of the gas; the hand-grenade must,
therefore, be thrown with great force to ensure the breakage of the said vessels.
Our improved hand-grenade differs from those heretofore used or designed in.
that it is made according to the principle set forth in the specification of former
Letters Patent dated 23rd April, A.D. 1884, No 6729, that is to say, it is so made
that it contains, in separate vessels or compartments, an alkaline solution and an
acid solution or other suitable chemicals, which are thus kept apart and prevented
from generating gas until the hand-grenade is thrown into the fire and the said
vessels or compartments are broken; and which will then combine and generate the
gas required for extinguishing the fire.
According to the most advantageous method of making our improved hand-
grenade, we take a bottle or vessel of glass or other suitable material divided into
two compartments, one of which we fill with an alkaline solution and the other
with an acid solution. This vessel must have a separate mouth or neck for each

page_text: compartment. After the said compartments are filled, they are properly closed or
sealed. The hand-grenade is then ready for use. Instead of employing a single
bottle or vessel, we sometimes use two separate vessels, one for the alkaline solution
and the other for the acid solution.
In the accompanying drawing, we have shewn the form in which we prefer to
make our said hand-grenade. a is a glass vessel somewhat similar in shape to
an ordinary water carafe or. decant r. This vessel is divided into two compart-
ments b, c by a vertical partition d. It is, moreover, provided with two mouths or
necks e, f, one for each compartment. By reason of the shape of the vessel a it will
rest or stand firmly or stably upon a flat surface. One of the compartments b, c is
filled with an alkaline solution and the other of the said compartments is filled with
an acid solution, and the said compartments are then properly closed or sealed, and
the hand-grenade is ready for use.
Our hand-grenade is to be used in a similar manner to the hand-grenades
heretofore made, that is to say, it must be thrown into, or upon, the fire to be
extinguished, in such a manner as to ensure the breakage of both the vessels
or compartments. But, as the glass or other material composing the vessel or
vessels, in our hand-grenade, is of much less thickness than in the hand-grenades
heretofore made, much less force is required to break the vessels or compartments.
When our hand-grenade is thus thrown into the fire and broken, the alkaline and
acid solutions escaping therefrom will combine and generate the gas on the spot
where it is required.
"
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In some cases, it may be necessary or desirable to use three or more different
chemicals, which must be kept separate until they are required for generating the
gas to extinguish the fire. In such cases, we use a vessel divided into three or more
compartments, or three or more vessels suitably connected or united.
We wish it understood that we make no claim, to the employment of two
or more glass vessels or to a single glass vessel divided into compartments, except
when used as above described for keeping the chemical solutions apart or separate
from each other until required for use for the purpose specified.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed we declare that what
we claim is
A hand-grenade wherein the alkaline and acid solutions or other chemicals are
kept in separate vessels or compartments, so that when, but not until, the said
vessels or compartments are broken, the said chemicals will combine and generate
the gas required for extinguishing the fire, as above set forth.
Data thin 96th dow of February 1885
HASELTINE, LAKE & Co.,
For the Applicant.