AN IMPROVED ARRANGEMENT FOR GUIDING ROAD STEAMERS OR COMMON ROAD LOCOMOTIVES ON STREET TRAMWAYS.
Year: 1871

page_text: LETTERS PATENT to Robert William Thomson, of Edinburgh, in the
County of Mid Lothian, North Britain, Civil Engineer, for the
Invention of "AN IMPROVED ARRANGEMENT FOR GUIDING ROAD STEAMERS
OR COMMON ROAD LOCOMOTIVES ON STREET TRAMWAYS.
Scaled the 5th March 1872, and dated the 13th September 1871.
•
PROVISIONAL SPECIFICATION left by the said Robert William
Thomson at the Office of the Commissioners of Patents, with his
Petition, on the 13th September 1871.
I, ROBERT WILLIAM THOMSON, of Edinburgh, in the County of Mid
Lothian, North Britain, Civil Engineer, do hereby declare the nature of
the said Invention for "AN IMPROVED ARRANGEMENT FOR GUIDING ROAD
STEAMERS OR COMMON ROAD LOCOMOTIVES ON STREET TRAMWAYS," to be as
follows, that is to say :-
i
This Invention relates to an improved arrangement for guiding road
steamers or common locomotives intended to draw carriages running on

page_text: tramways, such tramways consisting of two parallel lines of trams, onc
or both lines being grooved; and it consists in applying one or more
guiding wheels suitable for running in the groove or grooves of the
tramway. These guiding wheels are independent of and in addition
to the ordinary wheels of the road steamer. The guiding wheels are
by preference keyed to one axle placed in front of the leading wheel
or wheels of the road steamer, and they are arranged with levers or
screws so that they can readily be lowered to engage in the groove or
grooves of the tramway or be raised up, thus admitting of the road
steamer readily leaving the tramway when required. The wheels are
by preference of a comparatively small size and of little weight to be
kept down in the groove of the 'tramway by means of springs. When
these guiding wheels are used, the ordinary wheels of the road steamer
need not be provided with flanges, which would interfere with their
running on the ordinary road.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Robert William Thomson in the Great Seal Patent
Office on the 12th March 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
WILLIAM THOMSON, of Edinburgh, in the County of Mid Lothian, North
Britain, Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirteenth day of September, in the
year of our Lord One thousand eight hundred and seventy-one, in
the thirty-fifth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said Robert William Thomson,
Her special licence that I, the said Robert William Thomson, my
executors, administrators, and assigns, or such others as I, the said
Robert William Thomson, 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 ARRANGEMENT FOR GUIDING ROAD
STEAMERS OR COMMON ROAD LOCOMOTIVES ON STREET TRAMWAYS," upon the

page_text: condition (amongst others) that I, the said Robert William Thomson?
my executors or administrators, by an instrument in writing under my,
or their, or 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
Scal Patent Office within six calendar months next and immediately.
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Robert William Thomson, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement in writing, reference being had to the.
accompanying Drawings, that is to say :-
My said Invention relates to an improved arrangement for guiding
road steamers or common road locomotives intended to draw carriages
running on tramways, such tramways consisting of two parallel lines
of trams, one or both lines being grooved; and it consists in applying"
one or more guiding wheels suitable for running in the groove or
grooves of the tramway. These guiding wheels are independent of
and in addition to the ordinary wheels of the road steamer, and arc
arranged so that they can be readily lowered to engage in the groove
or grooves of the tramway or be raised up, thus admitting of the road
steamer readily leaving the tramway when required. When these
guiding wheels are used the ordinary wheels of the road steamer need
not be provided with flanges, which would interfere with their running
on the ordinary road.
And in order that my said Invention and the manner of performing
the same may be properly understood, I hereunto append a Sheet of
explanatory Drawings to be herein-after referred to, and representing a
simple and convenient mode of practically applying my improvements.
Figure 1 on the Sheet of Drawings is a plan, and Figure 2 is a side.
clevation showing (in outline) a road steamer as fitted with my improved
guiding appliances. A pair of small wheels 1, having their edges
shaped suitably for running in the grooves of the trams 2, are fixed
on an axle 3 fitted to run in eyes 4 in the ends of a pair of levers 5,
which are jointed or hinged to brackets 6 fixed to the road steamer
framing. The axle 3 is connected by links 7 (in the eyes of which
it can freely revolve) to levers 8 on a transverse horizontal rocking

page_text: shaft 9, carried upon the front of the road steamer framing, and this
rocking shaft 9 has fast on it a hand lever 10, by moving which the
guide wheels 1 can be raised or lowered as required, a catch plate 11
being provided for holding the hand lever in either position. Blade
springs 12 are shown as applied for pressing down the guide wheels 1,
when they are running in the tramway grooves; the guide wheels
may, however, be kept down sufficiently by their own weight.
preferred one or more screws may be used instead of the levers for
raising and lowering the guide wheels; and these wheels may be con-
nected to the road steamer framing in any convenient way.
Having thus particularly described my said Invention and the manner
of performing the same, I have to state that I do not restrict myself
to the precise details herein described or delineated, but that what I
believe to be novel and original, and claim as the Invention secured
to me by the herein-before in part recited Letters Patent is, the pro-
viding of road steamers or common road locomotives with independent
additional wheels for guiding them on tramways, and capable of being
raised when required as herein-before described.
In witness whereof, I, the said Robert William Thomson, have here-
unto set my hand and scal, this Ninth day of March, in the year
R. W. THOMSON. (L.S.)