AN IMPROVED METHOD OF APPLYING ELASTIC BEARINGS TO RAILROAD CHAIRS AND RAILS
Year: 1855

page_text: LETTERS PATENT to David L. Davis, of Dedham, in the County of Norfolk,
and State of Massachusetts, United States of America, for the Invention
of "AN IMPROVED METHOD OF APPLYING ELASTIC BEARINGS TO RAILROAD
CHAIRS AND RAILS."
Sealed the 3rd August 1855, and dated the 23rd May 1855.
PROVISIONAL SPECIFICATION left by the said David L. Davis at tho
Office of the Commissioners of Patents, with his Petition, on the 23rd
May 1855.
I, DAVID L. DAVIS, of Dedham, in the County of Norfolk, and State of
Massachusetts, United States of America, do hereby declare the nature of tho
Invention for "AN IMPROVED METHOD OF APPLYING ELASTIC BEARINGS TO RAILROAD
CHAIRS AND RAILS" to be as follows:-
Efforts have before been made to diminish the rigidity of the substructure of
railroads, and the injurious effects of this rigidity upon the rolling stock, by the
introduction of india-rubber or some other elastic substance between the sub-
structure and the rails. All efforts to accomplish this have, however, failed

page_text: on account of the difficulty experienced in preserving the elastic material
made use of from speedy destruction, and no means have heretofore been
devised of effecting this end. When the india-rubber has been placed beneath
the rail, and between it and the chair, it has invariably been rapidly destroyed
by the concussion and friction to which it was exposed, the india-rubber being
worn up into threads, which are forced out from beneath the rail. Where the
elastic material has been put beneath the chair, and between it and the
sleeper, the same destructive process went on, though not quite so rapidly as in
the former case.
To remove the above difficulty, and to enable me to interpose an elastic
substance between the substructure and the rail, is the object of my present
Invention, which consists in confining the india-rubber between plates upon
every side in such a manner, that while it shall be free to yield in a vertical
direction, it shall be subjected to no friction between the surfaces above and
below it, by which means the india-rubber is protected from the abrasion which
has heretofore so speedily destroyed it.
It is well known that the substructure of railroads cannot be laid in the
most permanent and substantial manner by the use of stone sleepers, on account
of the injury sustained by the rolling stock from the rigidity and want of
elasticity of the rails. By the interposition of an elastic substance between
the sleeper and the rail, this injurious wearing effect upon the engines would
be avoided, and the roads might thus be laid in a more permanent manner
than has heretofore been found practicable.
It is preferred that the india-rubber should be confined upon all sides within
a chamber, formed by the chair and a stationary plate and flanges; but it is
evident that the same end may be effected by placing the india-rubber within a
cavity in the chair; the object in either case being to prevent it from being
pressed out laterally and gradually destroyed by friction.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said David L. Davis in the Great Seal Patent Office on the
13th October 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DAVID
L. DAVIS, of Dedham, in the County of Norfolk, and State of Massachusetts,
United States of America, Road Master, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-third day of May, in the year of our Lord
One thousand eight hundred and fifty-five, in the eighteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said David L. Davis, Her special licence that I, the said David L. Davis,
my executors, administrators, and assigns, or such others as I, the said
David L. Davis, 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 "AN IMPROVED
METHOD OF APPLYING ELASTIC BEARINGS TO RAILROAD CHAIRS AND RAILS," upon
the condition (amongst others) that I, the said David L. Davis, by an instru-
ment in writing under my hand and seal, 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 David L. Davis, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, together with the Drawing hereto annexed, that is to say :-
Fig. 1 is a plan of a chair having my improvements attached; Fig. 2, a
section upon the line A, A; Fig. 8, a section upon the line B, B.
The effort has frequently been made to diminish the rigidity of the sub-
structure of railroads, and the injurious effects of this rigidity upon the rolling
stock, by the introduction of india-rubber or some other elastic substance
between the substructure and the rail. All efforts to accomplish this have,
however, signally failed, on account of the difficulty experienced in preserving
the elastic material made use of from speedy destruction, and no means have
heretofore been devised of effecting this end. When the india-rubber has
been placed beneath the rail, and between it and the chair, it has invariably
been rapidly destroyed by the concussions and friction to which it was exposed,.
the india-rubber being worn up into threads which are forced out from beneath.
the rail. Where the elastic material has been put beneath the chair, and
between it and the sleeper, the same destructive process went on, though not
quite so rapidly as in the former case.
To remove the above difficulty, and to enable me to interpose an elastic

page_text: substance between the substructure and the rail, is the object of my present
Invention, which consists in confining the india-rubber between plates upon
every side in such a manner, that while it shall be free to yield in a vertical
direction, it shall be subjected to no friction between the surfaces above and
below it, by which means the india-rubber is protected from the abrasion which
has heretofore so speedily destroyed it.
To enable others skilled in the art to understand my Invention, I will pro-
ceed to describe the manner in which I have carried it out.
In the accompanying Drawings, C is a chair of the usual construction, upon
which is placed the india-rubber D. This is covered by an iron plate E, so formed
and applied to the chair as to be incapable of any motion except in a vertical,
direction, it being closely fitted between the sides of the chair, as seen in Fig. 2,
while the flanges I effectually prevent any motion in a longitudinal direction.
The india-rubber is thus protected from friction, and is not deteriorated and
destroyed in the manner above referred to. In order to allow it to yield in a
vertical direction, the india-rubber may be made slightly smaller than the
cavity or space in which it is confined, or the same end may be effected by
making a hole in the centre of it to allow it to yield in this direction.
It is well known that the substructure of railroads cannot be laid in the
most permanent and substantial manner by the use of stone sleepers, on
account of the injury sustained by the rolling stock from the rigidity and want
of elasticity of the rails. By the interposition of an elastic substance between
the sleeper and the rail, this injurious wearing effect upon the engines would be
avoided, and the roads might thus be laid in a more permanent manner than
has heretofore been found practicable. In winter also, when the ground is
frozen, the whole substructure becomes a solid rigid mass, and it is estimated
that the rolling stock is deteriorated by this circumstance as much during the
three months of winter as in the other nine months of the year. This would
also be avoided by the use of my improvement, and I therefore propose to apply
it to all railroad chairs, whether they rest upon wooden or stone sleepers.
In the accompanying Drawings the india-rubber is represented as confined
upon all sides within a chamber, formed by the chair and a stationary plate
and Hanges; but it is evident that the same end may be effected by placing
the india-rubber within a cavity in the chair, the object in either case
being to prevent it from being pressed out laterally, and gradually destroyed
by friction.
In the above description my Invention is spoken of as particularly applicable
to railroad chairs; it is my intention, however, to apply it to railroad frogs, and

page_text: the head and tail blocks of switches, or whenever it may be necessary to sub-
ject india-rubber cushions or springs to pressure and wear, similar to that which
they receive beneath railroad rails.
What I claim as my Invention, and desire to secure by Letters Patent, is,
the within-described method of confining the india-rubber between horizontal
plates, for the purpose set forth.
Witness,
SAM. COOPER,
39, State St., Boston, U. S. A.
DAVID L. DAVIS. (L.S.)