Improvements in Envelopes.
Year: 1891

page_text: Date of Application, 23rd Nov., 1891-Accepted, 19th Mar., 1892
COMPLETE SPECIFICATION.
Improvements in Envelopes.
I, CARL BLANKE of Barmen, Kaiserstrasse No. 3 Rhenish Prussia Germany
Manufacturer do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and by
the following statement :-
The object of iny invention is to be able to enclose and secure those mailable
matters that are allowed to go at a lower rate, such as business papers, printed
matters and the like, in such a manner that their inspection is possible without
opening the envelope or rather to enable the mailing of those matters in closed
envelopes, out of which they cannot be lost and into which no other smaller matters
can be slipped, as is the case with the ordinary cross bands now in use at the same
time my new envelope which I call, look through envelope" has for its object,
whilst it allows sufficient inspection for the post official, to hinder the removal of
the contents from it and thus to prevent their loss and their being damaged.
The new envelopes are made in various manners, some of which are shown in the
annexed drawing.
Fig. 1 shows an envelope with round looking holes,
"
2 shows an envelope with oval transversal holes,
3 shows an envelope with oblong rectangular holes,
"
"
4 shows an envelope with single slots,
"
دو
5 shows an envelope with looking holes cut in longitudinal direction,
6 shows the manner of holding the envelope for inspection.
The principle of my invention is based on the fact that any wrapper of paper or
similar material, when held in the hand as shown by Fig. 6 and the edges are
slightly pressed together, will spread out like a balloon but the more so, when the
transverse edges are weakened by partly cutting the material through by holes of
any shape or simple slots, which may be made in regular order or not, as indicated
in the various figures, and when one blows through these holes. A, Fig. 1, being
round holes; B, Fig. 2 showing oval holes and Fig. 3 shows an envelope with
oblong rectangular holes, whereas in Fig. 4 an envelope is shown having only
transverse slots D cut into it; Fig. 5 is provided with holes E, cut lengthways and
across the transverse edge.
The holes may be cut at one side only or on both sides, as indicated in dotted
lines in the various figures.
Now when such a look through envelope is held in the hand and one blows
into it through the holes it spreads out and allows inspection of the interior without
requiring opening.
For the sender of the letter it has the great advantage that the contents are not
lost and not spoiled and for the Post Office it offers the safe conveyance and
prevents loss of other pieces, post cards, for instance, which now can not any more
slip between sendings of this class.
Having now particularly described and ascertained the nature of ny said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:
The making of envelopes called "look through envelopes" having one or two
opposite sides perforated by variously shaped holes or slots, so as to allow the

page_text: inspection of the interior without requiring the opening of the envelope as shown
and described and for the purpose set forth.
Dated this 14th Hor of November 1201
KARL S. MAYER,
Agent for C. Blanke.