Improved Means for Sealing Letters, Parcels, and other Objects.
Year: 1890

page_text: Date of Application, 1st July, 1890
Complete Specification Left, 1st Apr., 1891-Accepted, 6th June, 1891
PROVISIONAL SPECIFICATION.
Improved Means for Sealing Letters, Parcels, and other Objects.
I, GUSTAV ADOLF HARDT, Civil Engineer, of 47, Hohestrasse Cologne,
Germany do hereby declare the nature of my invention to be as follows:-
The present invention consists in a new adhesive seal of paper, cloth or similar
material, to be applied to letters, parcels and other articles, in order to prevent or
detect the surreptitious opening of the same.
The essential feature of the invention is the fact, that the seal, after it has been
once applied, renders every injury or attempt to open the letters conspicuous,
whether moisture has been applied or not, that is to say, whether the seal has been
cut or torn, or whether it has been removed bodily by dissolving the adhesive
substance, and subsequently put on again.
The seal is not only provided with serrated or toothed edges, but also with
perforations, in order to render it more easily destructible, to form blanks in the
place where the seal is applied, and to render its removal more difficult.
The seal is made of thin transparent paper which gives off colour when
moistened, or which changes the colour, and the seals differ from one another as
regards their shape and colour; consequently, if they are removed in a moist
condition, and exchanged, they change not only their colour, but also their shape,
thus rendering it impossible to detach a seal and to replace it by another.
The seal may have any convenient shape, care being taken to render the
indentations at the edges as irregular as possible.
The blanks left in the seals may have the shape of letters or words. As the
seals give off colour, the parts of the envelope or other surface corresponding to the
blanks or perforations of the seals, retain their original colour, while the other parts
are coloured differently, which renders it still more difficult, to replace a detached
seal by a new one.
In order to increase the strength of the seal, and to render any injury to the
same more conspicuous, the seal is traversed by two threads laid cross-wise, or
by several threads placed side by side and one over the other, so that an injury
produced by an attempt to remove the seal would be shown by the condition of the
strings, which cannot be replaced into their normal position after having been once
deranged.
The usual stamping of the seal, with printers' ink &c., after they have been
gummed on, increases their safety, because they contain blanks or perforations, and
after having been once detached, cannot be replaced uninjured on the old spot.
If desired, initials, names, or other designations may be printed on the face or on
the back of the seal, which impression would be mutilated in case of any injury to
the seal and thus provide a further proof of an unauthorized interference.
Dated this lot d f I.1 1000
FAIRFAX & WETTER,
433, Strand, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improved Means for Sealing Letters, Parcels, and other Objects.
I, GUSTAV ADOLF HARDT, Civil Engineer, of 47, Hohestrasse, Cologne,
Germany, do hereby declare the nature of my invention and in what manner the
same is to be performed, to be particularly described and ascertained in and by
the following statement :-
The present invention consists in a new adhesive seal of paper, cloth or similar

page_text: material, to be applied to letters, parcels and other articles, in order to prevent or
detect the surreptitious opening of the same.
The essential feature of the invention is the fact, that the seal, after it has been
once applied, renders any injury or attempt to open the letters conspicuous; whether
moisture has been applied or not, that is to say, whether the seal has been cut or
torn, or whether it has been removed bodily by dissolving the adhesive substance,
and subsequently put on again.
In the following description, reference will be made to the accompanying drawing,
Figs. 1 and 2.
The seal is not only provided with serrated or toothed edges, but also with
perforations, in order to render it more easily destructable, to form blanks in the
place where the seal is applied, and to render its removal more difficult.
The seal is made of thin transparent paper, and provided on its gummed
underside with a design or words printed in copying ink, so that the seal gives off
colour when moistened, and different seals differ from one another as regards their
shape and colour; consequently, if a seal is moistened and removed from the
envelope, and another seal put in its place, both the colour and the shape of the
seal will have been changed, and it is very difficult, if not impossible, to detach a
seal and then replace it by another without detection.
Instead of the rectangular shape, shown by Figs. 1 and 2, the seal may have any
other convenient shape, and the indentations at the edges may be irregular.
The perforations or blanks formed in the seals may have the shape of letters or
words. As the seals give off colour, the parts of the envelope or other surface,
corresponding to the blanks or perforations of the seals, retain their original colour,
while the other parts take the colour of the ink on the underside of the seal, which
renders it still more difficult, to replace a detached seal by a new one.
In order to increase the strength of the seal, and to render any injury to the
same more conspicuous, the seal is traversed by two threads laid crosswise, or by
several threads placed side by side and one over the other, so that any injury
produced by an attempt to remove the seal would be shown by the condition of the
threads, which cannot be replaced into their normal position after having been once
deranged. The said threads may be sewn into the paper by means of a lock-stitch
sewing machine.
The usual stamping of the seal, with printers' ink &c., after they have been
gummed on, increases their safety, because they contain blanks or perforations, and
after having been once detached, the seals cannot be replaced uninjured on the
old spot.
If desired, initials, names, or other designations may be printed on the face or on
the back of the seal, which impression would be mutilated in case of any injury to
the seal and thus provide a further proof of unauthorized interference.
Having now particularly described and ascertained my said invention, and in
what manner the same is to be performed, I declare, that I claim :-
1. A transparent seal for letters, parcels and other objects, strengthened with
threads and provided on its gummed underside with copying ink, substantially as
described, and for the purposes specified.
2. A detective seal of thin transparent paper, serrated and perforated as
described, the said seal being strengthened with threads or stitches and provided
on its gummed underside with an impression of copying ink, substantially as
described and for the purposes specified.
G. AD. HARDT.
By Fairfax & Wetter,
433, Strand, London, Agents.