IMPROVEMENTS IN ENVELOPES
Year: 1868

page_text: LETTERS PATENT to William Wootton, of Westminster Bridge Road,
in the County of Surrey, for the Invention of "IMPROVEMENTS IN
ENVELOPES."
Scaled the 7th August 1868, and dated the 12th February 1868.
PROVISIONAL SPECIFICATION left by the said William Wootton at
the Office of the Commissioners of Patents, with his Petition, on
the 12th February 1868.
I, WILLIAM WOOTTON, of Westminster Bridge Road, in the County
of Surrey, do hereby declare the nature of the said Invention for "Im-
PROVEMENTS IN ENVELOPES," to be as follows:-
Ordinary adhesive envelopes can be easily opened by the application
of either moisture or heat, the former soaking through the paper and
dissolving the mucilage, the latter making the gum crack, and for the
time destroying its adhesive properties; the contents of envelopes so
secured can be abstracted or read and replaced, and the laps afterwards
stuck down so as to avoid detection. .

page_text: This Invention has for its object the production of adhesive envelopes
that cannot be opened by either of those means without being so defaced
as to show they had been tampered with. To prevent opening by steam
or water I apply to the under part of the lap of the envelope a thin
coating of a composition of shellac and spirit or naptha, to which a
small quantity of gum benzoin may be added; the white or bleached
shellac is preferred, as that renders the mixture as near as possible the
color of the mucilage which is next applied. This composition is
superior for the purpose to other waterproofing compound as it has the
properties of not staining the paper or rendering it too tough; and what
is most important leaves a surface to which the mucilage firmly adheres,
When necessary the waterproof composition may be applied to the lower
part of the envelope where the side pieces overlap and are gummed to
the bottom flap, as those parts may be easily operated upon by damping.
To prevent the envelopes being opened by heat without showing that
such agency had been used, I apply to the back of the envelopes a minute
quantity of diluted sulphuric acid or other chemical agent that has the
property when heated of charring or discoloring the paper. If acid is
not used a mixture of sulphate of copper, carbonate of soda, and
ammonia, or other sympathetic ink will answer the purpose, or a color
may be stamped or printed on the envelope that would change when
exposed to the action of heat, Envelopes prepared as I describe can be
wetted and stuck down with the same facility as ordinary adhesive
envelopes, and possess the very great advantage of making apparent
any attempt to open them.
Also according to my Invention I make an envelope with a pouch or
pocket (which should be of linen or some tough fabric), which pouch is
of much smaller size than the exterior envelope; and is fixed in the
middle of it, so as to be kept as far as possible from the edges; the
object is to prevent loss which frequently occurs in sending coin or
trinkets through the post from the edges of the envelopes being cut and
the contents so abstracted. Or the pouch may be fixed to a card the size
of the outside envelope, which can be taken out and replaced, and so
more conveniently filled and secured.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Wootton in the Great Seal Patent Office
on the 12th August 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
WOOTTON, of Westminster Bridge Road, in the County of Surrey, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twelfth day of February, in the
year of our Lord One thousand eight hundred and sixty-eight, in
the thirty-first year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said William Wootton, Her
special license that I, the said William Wootton, my executors, adminis-
trators, and assigns, or such others as I, the said William Wootton, 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, usc, exercise,
and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN ENVELOPES," upon the condition (amongst others) that I, the said
William Wootton, my exccutors or administrators, by an instrument in
writing under my, or their, of 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
same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Wootton, do hereby
declare the nature of the 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, that is to say :-
Ordinary adhesive envelopes can be easily opened by the application
of either moisture or heat, the former soaking through the paper and
dissolving the mucilage, the latter making the gum crack and for the
time destroying its adhesive properties; the contents of envelopes so
secured can be abstracted or read and replaced, and the laps afterwards
stuck down so as to avoid detection.
This Invention has for its object the production of adhesive envelopes
that cannot be opened by either of those means without being so defaced

page_text: as to shew they had been tampered with. To prevent opening by steam
or water I apply to the under part of the lap of the envelope a thin coating
of a composition of shell lac and spirit, or naptha, to which a small
quantity of gum benzoin may be added; the white or bleached shell lac
is preferred as that renders the mixture as near as possible the color of
the mucilage which is next applied. This composition is superior for
the purpose to other waterproofing compound, as it has the properties
of not staining the paper or rendering it too tough, and what is most
important leaves a surface to which the mucilage firmly adheres. When
necessary the waterproof composition may be applied to the lower part
of the envelope where the side pieces overlap and are gummed to the
bottom flap, as those parts may be easily operated upon by damping.
In place of the waterproofing material being applied to the interior of
the envelope, it might be applied to its exterior, but not I believe so
advantageously. To prevent the envelopes being opened by heat
without shewing that such agency had been used, I apply to the back
of the envelopes a minute quantity of diluted sulphuric acid or other
chemical agent that has the property when heated of charring or
discoloring the paper. I prefer to employ the acid of a strength of
about one part acid of commerce to eleven parts water. If acid is not
used a mixture of sulphate of copper, carbonate of soda, and ammonia,
or other sympathetic ink, will answer the purpose, or a color may be
stamped or printed on the envelope that would change when exposed to
the action of heat. Envelopes prepared as I describe can be wetted
and stuck down with the same facility as ordinary adhesive envelopes,
and possess the very great advantage of making apparent any attempt
to open them.
Also according to my Invention I make an envelope with an internal
pouch or pocket, which is by preference of linen or some tough fabric,
and made up like an ordinary envelope. The pouch is made smaller
than the exterior envelope and fixed in the middle of it, the flap of the
pouch being towards the back of the outer envelope. The edges of the
outer envelope, which project beyond the sides and bottom of the inner
pouch, are gummed or pasted together, so as to prevent the edges being
cut without shewing a slit prominently on the front or back of the
envelope, and this cement also serves to hold the inner pouch in its
place. The size of the pocket will depend upon the class of articles
which it is intended to place in it. If it be for small articles of jewellery

page_text: it may be considerably smaller that the outer envelope, but if it be
intended to place larger articles in the pocket, the pocket may be made
to extend to within about a quarter of an inch of the outer envelope. As
above mentioned the pouch or pocket opens inwards, and waterproofing
and mucilage is applied to the inner face of the outer envelope, so when
the pouch is filled and the envelope wetted down the contents cannot
be abstracted without tearing that part of the envelope on which the
address is written. When using an envelope the back and front of
which is pasted together around the side and bottom edges, as above
described, the inner pouch or pocket may be fixed to a card which can
be taken out and replaced and so more conveniently filled and secured.
In witness whereof I, the said William Wootton, have hereunto
set my hand and seal, this Eleventh day of August, in the year
of our Lord One thousand eight hundred and sixty-eight.