IMPROVEMENTS IN WINDOW SASH FASTENINGS
Year: 1874

page_text: LETTERS PATENT to Joseph Timothy Hopkinson, of 110, Newington
Causeway, in the County of Surrey, Tool Maker, for the Invention
of "IMPROVEMENTS IN WINDOW SASH FASTENINGS."
Sealed the 21st August 1874, and dated the 24th February 1874.
T
PROVISIONAL SPECIFICATION left by the said Joseph Timothy
Hopkinson at the Office of the Commissioners of Patents, with
his Petition, on the 24th February 1874.
I, JOSEPH TIMOTHY HOPKINSON, of 110, Newington Causeway, in the
County of Surrey, Tool Maker, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN WINDOW SASH FASTENINGS," to be as
follows:-
The object of my Invention is to construct a window sash fastening
in such manner that while it shall be perfectly simple and resemble
ordinary sash fastenings, it cannot be opened from the outside .by a
knife or other instrument passed up through the opening between the
sashes.

page_text: And my Invention consists in forming a notch or recess in the leg of
the fastening, that is to say, in that part which is carried by the back
half of the fastening, and is moved round under the quadrant on the
front half in order to secure the sashes. Tho said notch is in such
position on the left side of the leg as to come above the opening between
the sashes when the fastening is secured (or it may be a little beyond
the opening and over the upper sash) so that a knife or instrument
pushed up between the sashes for the purpose of pushing back the leg
enters the notch. Now as soon as the knife in the attempt to push
round the leg on its centre brings that point of the notch against which
it acts immediately above the edge of the upper sash, which it will do
almost at once, it is unable to push it any further, because while the
knife must move, if at all, in the line of the opening between the sashes,
the part of the notch against which it is acting must move, if at all,
over the surface of the upper sash; and as the two cannot move together
in different directions the knife becomes as it were jammed.
In some cases I combine with the notch a projection in front of the
same on the left side of the leg, so that in case of the opening between
the sashes being wide enough to allow a knife to be got against the leg
in front of the notch, the projection will, as soon as the leg commences
to move round, jam the knife against the lower sash. To prevent the
leg being moved by an instrument forced up against its under side I
make a bevelled recess or slot in the under side, so that such instrument
as soon as pressure is exerted thereon will at once slip against or
towards the edge of the upper sash where it will be jammed for a
similar reason to that herein-before explained.
My Invention further consists in making the hole for the pin on
which the leg turns of slot form or elongated, the elongation being
transverse or nearly so, and curved or not. The effect of this is that if
a knife pushed up between the sashes is forced against the leg, the leg
moves so as to bring the pin from the right end to the left end of the
slot, and the right hand back corner of the leg being then a greater
distance from the pin, will, when the leg is moved partly round, jam the
ordinary spring against the back upright plate of the fastener and
thereby prevent the leg being moved any further...
My Invention further consists in making a projection on the bottom
plate of the back half of the fastener at the left of or beneath the leg
when pulled round such projection, standing out horizontally from the

page_text: front edge of the plate so as to overlap or partly overlap the lower sash.
The ordinary bevelled back edge of the lower sash must have a piece cut
away to allow the projection to pass when either of the sashes has to
be opened. If a knife or other instrument be pushed up through the
opening between the sashes with the object of pushing round the leg,
the said instrument is unable to get at the leg owing to this projection.
Although this projection may be a simple horizontal projection, it
may, if preferred, be carried up vertically so as to be of ✓ shape, and
again turned over at the top into shape, when it will as. it were
embrace the leg.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph Timothy Hopkinson in the Great Seal Patent
Office on the 24th August 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
TIMOTHY HOPKINSON, of 110, Newington Causeway, in the County of
Surrey, Tool Maker, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fourth day of February, in the
year of our Lord One thousand eight hundred and seventy-four, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Joseph Timothy Hopkinson,
Her special licence that I, the said Joseph Timothy Hopkinson, my
executors, administrators, and assigns, or such others as I, the said
Joseph Timothy Hopkinson, 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 WINDOW SASH FASTENINGS,"
upon the condition (amongst others) that I, the said Joseph Timothy
Hopkinson, my executors or administrators, by an instrument 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

page_text: same to be filed in the Great Scal Patent Office within six calendar
months next and immediately after the dato of the said Letters
Patent.
NOW KNOW YE, that I, the said Joseph Timothy Hopkinson, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement thereof, reference being had to the
accompanying Drawings, that is to say :-
The object of my Invention is to construct window saslı fastenings in
such manner that while they shall be perfectly simple and resemble
ordinary saslı fastenings, they cannot be opened from the outside by a
knife or other instrument passed up through the opening between the
sashes.
;
And the first part of my Invention consists in forming a notch or
recess in the leg of the fastening, that is to say, in that part which is
carried by the back half of the fastening, and is moved round under
the quadrant on the front half in order to secure the sashes. Figure 1
of the annexed Drawings is a plan view of the leg a of a fastening
formed with a notch or recess according to my Invention. The said
notch is in such position on the left side of the leg as to come above the
opening between the sashies when the fastening is secured (or it may be
a little beyond the opening and over the under sash) as represented in
Figure 2, which is a plan view of the complete fastening so that a knife
or instrument pushed up between the sashes for the purpose of pushing
back the leg enters the notch. Now as soon as the knife in the attempt
to push round the leg a on its centre brings that part of the notch 6
against which it acts immediately above the edge of the upper sash,
which it will do almost at once, it is unable to push it any further,
because while the knife must move, if at all, in the line of the opening
between the sashes, the part of the notch against which it is acting must
move, if at all, over the surface of the upper sash; and as the two cannot
move together in different directions the knife becomes as it were
jammed.
My Invention consists, secondly, in making a projection on the back
half of the fastening at the left of or beneath the leg when pulled round,
such projection standing out from the back half so as to overlap or
partly overlap the lower sash. Figure 3 is a plan, and Figure 4 a trans-
verse section of a fastening provided with a projection a on the back half

page_text: as just described. Figure 5 is an elevation of the back half. The
ordinary bevelled back edge of the lower sash must have a piece cut
away as seen at 6 to allow the projection a to pass when either of the
sashes has to be opened. If a knife or other instrument be pushed up
through the opening between the sashes with the object of pushing
round the leg, the said instrument is unable to get at the leg owing to
this projection a.
Although this projection may be a simple horizontal projection as
represented at a, it may, if preferred, be carried up vertically as
represented at c, Figures 3 and 5, so as to be of L shape, and again
turned over at the top as represented at d into shape, when it will,
as it were, embrace the leg.
I have herein-before described and shown the fastening as made to
work from right to left in securing the window, as is usually the case;
but if it be made to work from left to right, the position of the parts
must of course be made to correspond.
In witness whereof, I, the said Joseph Timothy Hopkinson, have
hereunto set my hand and seal, this Twenty-first day of August,
One thousand eight hundred and seventy-four.