IMPROVEMENTS IN PERMANENT LETTER FILES
Year: 1877

page_text: LETTERS PATENT to Bristow Hunt, of Serle Street, Lincoln's Inn, in the County
of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS IN PERMANENT
LETTER FILES." A communication from abroad by Bloomfield Brower (Sta
tioner), of New York, and John Francis Adams (Gentleman), of Irvington, both
in the State of New York. in the United States of America.
COMPLETE SPECIFICATION filed by the said Bristow Hunt at the Office of the
Commissioners of Patents on the 23rd June 1877.
BRISTOW HUNT, of Serle Street, Lincoln's Inn, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN PERMANENT LETTER FILES." A communication
from abroad by Bloomfield Brower (Stationer), of New York, and John Francis
Adams (Gentleman), of Irvington, both in the State of New York, in the United
States of America.
This Invention, which relates to certain new and useful improvements in per-
manent letter files, consists principally of a letter file having index leaves adjustable
in a binding back to permit the introduction between them of loose sheets, letters,
notes, or papers, the back being independently removable from a holder. The In-
vention however embodies other features, which will be herein-after more par-
ticularly referred to.
The Invention is illustrated on the accompanying Sheet of Drawings, in Figures
1 to 11, of which,―
Figure 1 represents a perspective view of the holder with its cover removed;
Figure 2, a similar view with the cover introduced under the index leaves.
Figure 3, a perspective view of the file complete with its cover in a closed
position; Figure 4, a longitudinal section thereof.
Figure 5, a perspective view of the back in which the index leaves are bound.
Figure 6, a perspective view of a modification of the holder, also showing a
modification of the back, and the method of binding the index leaves therein.
Figure 7, a perspective view of another modification of the binding back.
Figure 8, perspective views of index leaves, shewing different modes of strength-
ening their binding edges.

page_text: Figure 9, a plan view of one of the index leaves, shewing a binding cord or tape
by which the leaves may be tied up in a pack when removed from their holder.
Figure 10, a perspective view of the index leaves when tied up in a pack or
bundle; and Figure 11, a plan view of a supplemental index.
A represents a rectangular box or holder open at the top and one end, and pro-
vided with grooves 2, 4, in the top and bottom of its sides, in which grooves the
edges of the top plate C of a rectangular cover B can slide. The top plate C is
extended such a distance as to cover the open top of the holder A when it is slid in
the grooves 2, see Figure 3; and the sides or edges 3 of both cover and box are
curved to conform to each other, and thus form a closed box; the bottom plate D'
of the holder is also protruded to enter grooves made in the inner side of the
cover.
The binding back D consists of a narrow rectangular box with an open front, and
in it the index leaves are secured by such means as will permit their free vertical
movements, as will presently be more fully described. It is made of such dimen-
sions as to permit its introduction into recesses 6 formed in the sides of the holder A.
When thus introduced it will rest against the back board E of the holder A, and
the index leaves will lay out flat in the holder and rest upon its bottom plate.
The leaves and their binding backs may thus be removed and introduced vertically
into the holder. A flat spring S pivotted to the inclined upper edge of the back
board is adapted to protrude into the holder and bear upon the index leaves, and
hold them compressed in their smallest compass, in which position it serves to hold
the binding back in place. This spring can be turned back (see Figure 2) so as to
allow of the removal of the binding back, index leaves, and papers.
Thus constructed the file may be used as follows:-By moving the spring S side-
ways or slightly raising it a letter or other sheet may be placed loosely between
any two of the index leaves, when upon returning the spring to its former position
or releasing it it again presses upon and securely holds the index leaves. When
such a number of loose sheets have been introduced as fill the index leaves to their
fullest capacity (it being understood that attaching strips 1, by which they are held
in the binding back, permit them to separate and expand to a size nearly equal to
the height of the sides of the holder) the spring S may be turned out of the way,
as shown, so that the binding back, together with the index leaves and their con-
tents, may then be removed bodily, as in Figure 10, and a new binding back with
its index leaves introduced.
In ordinary business transactions it takes a considerable time to fill one of these
files, and therefore in order to adapt them to receive additions from time to time,
and to permit reference to be readily made to their contents, as well as to provide
their contents with a protection from dust, the sliding cover C may be introduced
in the lower grooves 4, as before referred to, and a spring T, which is pivotted to
the end piece G, placed in the position shewn in Figure 2, where it bears upon the
front edges of the index leaves, holding them in place as the thickness of the index
leaves is increased by the introduction of filed papers. This spring so used is not
herein claimed, and it is obvious that when it is employed the spring S may be
omitted and any removable stop holding the binding back vertically in place may
be employed. But when this cover is used to close up the holder, as in Figure 3,
the spring Tinay be turned upon its pivot so as to occupy the position shown in
Figure 4, where it compresses the index leaves and prevents the matter filed
between them from being disturbed by any movement imparted to the holder. In
this use of the spring T the presence of the spring S is not essential, or it may be
supplanted by a third spring R attached to the bottom plate O of the cover, and
which spring will press down the main body while the spring T presses the edges
of the index leaves.
It is apparent that the structure of the holder may be varied so long as it
embodies recesses 6, which, while holding the binding back in place in the holder,
perimit its vertical removal. Thus, as in Figure 6, said recesses 6 are formed in a
box having thin sides H to which vertical ribs I are fastened. The holder in this

page_text: example also has its cover J hinged to the back, and its front K is hinged to the
bottom so as to swing down.
The index leaves have affixed to their back edges flexible rods or plates 1, which
are prolonged beyond the side edges of the leaves, and may be sprung into the
recesses formed between the side plates a, o, of the binding back D, in which
recesses they are free to move up and down, according as the index leaves are
separated by the matter introduced between them. In this structure of course the
plate o like the plate a may be quite short, though the latter is required to be so
made to accommodate the index leaves.
The binding back shewn in Figure 7 is an open framework, preferably of metal, con-
sisting essentially of top and bottom plates m, n, end plates u, and sheet supporting
rods t (see Figures 6 and 7). The index leaves are perforated near their back edges
and strung upon the rods t, which are permanently fastened in place in the
plates m, n. As the papers filed between the index leaves accumulate they raise
the leaves and as it is important that the binding or back edges of the leaves
shall rise bodily and not jam or bend at their ends they may be provided with
a material, which not only renders said edges stiff and rigid, but imparts a strength
thereto which will resist strains exerted upon their points of attachment. In
Figure 8 three examples of this are shown, representing a strip of wood or similar
rigid material attached to the index leaf at the rear of its point of attachment.
illustrates a similar strip perforated by the attaching holes; z indicates a similar
strip placed in front of the attaching point. These strips may be secured to the
leaves in any approved manner.
When the set of index leaves filled with filed matter and held together by the
binding back is removed bodily from the holder it is important that the free front
edges of its leaves shall be secured together. This may be done by a binding strap
of any form; but it is desirable that the file shall comprise in itself all the necessary
adjuncts to its perfect operation from being held conveniently for the reception of
loose papers from time to time to its being removed and tied or bundled up for
storage. One or more binding cords or bands c are therefore attached to one of
the outer leaves by being threaded through the same, their free ends being pasted
at p, or temporarily fastened down by any means which will provent them from
becoming tangled or interfering with the file until they are needed for binding up
the same.
When the leaves are removed from the holder the ends of these bands
are detached and the bands are made to envelope the package, as in Figure 10.
As it sometimes occurs that the user of such files desires a different index or
requires some change in the one attached to the leaves this file is furnished with a
supplemental index, as in Figure 11, temporarily attached to some part of the file,
and gummed upon its back ready for use.
Having now described the nature and object of the said Invention together with
the manner in which the same is to be or may be performed or carried into practical
effect, I would remark in conclusion that I claim as the Invention communicated
to me by the above-mentioned Bloomfield Brower and John Francis Adams,
First. A letter file consisting of a holder having vertical recesses (6) and a series
of leaves held in a binding back, which is capable of introduction and removal
vertically from said holder, substantially as described.
Second. The detached binding back consisting of a framework supplied with
means, substantially as described, holding the index and leaves providing for their
vertical adjustment.
Third. The combination with a pack of sheets or index leaves, held at one end
in a holder or file, of a swinging spring S attached to said holder or file so as to
bear the free ends of said sheets to hold them or swing away to release them,
substantially as described.
upon
Fourth. The combination of the swinging spring S with the holder provided
with vertical recesses 6, and the removable binding back D, substantially as
described.

page_text: Fifth. The combination of the swinging spring T with the cover B, the holder A,
and the index leaves, substantially as described.
Sixth. The binding back D, consisting of plates m, n, u, and rods t, substantially
as described.
Seventh. The combination with a pack of index leaves of the binding cord
or band c attached thereto, and adapted for operation, substantially as described.
Eighth. The combination of the spring R with the cover B and the holder A,
substantially as, described.
Ninth. The combination with a paper file of a supplemental index (Figure 11),
substantially as described:
In witness whercof, I, the said Bristow Hunt, have hereunto set my hand
and seal, this Twenty-second day of June, in the year of our Lord One
thousand eight hundred and seventy-seven.
BRISTOW HUNT. (L.S.)