CERTAIN IMPROVEMENTS IN TWO AND FOUR WHEELED CARRIAGES
Year: 1846

page_text: AITKEN'S SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,: WILLIAM
AITKEN, of Aberdeen, in the County of Aberdeen, Gentleman, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Fifteenth day of August,. One thousand eight hundred and
forty-six, in the tenth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said William Aitken, my exors,
admñňors, and assigns, Her especial licence, full power, sole privilege and
authority, that I, the said William Aitken, my exors, admňors, and assigns, or
such others as I, the said William Aitken, my exors, admors, or assigns, should
at any time agree with, and no others, from time to time and at all times
thereafter during the term of years therein expressed, should and lawfully
might make, use, exercise, and vend, within England, Wales, and the Town
of Berwick-upon-Tweed, and in all Her Majesty's Colonies and Plantations
abroad, and also in the Islands of Jersey, Guernsey, Alderney, Sark, and Man,
my Invention of "CERTAIN IMPROVEMENTS IN TWO AND FOUR WHEELED CARRIAGES;"
in which said Letters Patent is contained a proviso,, that I, the said William
Aitken, shall cause a particular description of the nature of the said Invention,
and in what manner the same is to be performed, by an instrument in writing
under my hand and seal, to be enrolled in Her Majesty's High Court..of
Chancery within six calendar months next and immediately after the date of
the said in part recited Letters Patent, as in and by the same, reference being
thereunto had, will more fully and at large appear.

page_text: NCW KNOW YE, that in compliance with the said proviso, I, the said
William Aitken, hereby declare that the nature of the said Invention, and in
what manner the same is to be performed, are fully described in and by the
present Specification thereof, reference being had to the Drawings hereunto
annexed, that is to say:-
My Invention consists, firstly, of certain improved combinations of materials
for the formation of the body parts of two and four wheeled carriages, whereby
the same may be increased in strength and rendered lighter than as at present
usually constructed. I make the framework of pieces composed partly of iron
and parly of wood, using the iron for the outsides of each piece and the wood
as a filling up. The iron for framework I make of three different forms:-
First, of the form commonly known as angle iron, of which Figure 1 is a
cross section; second, of a U form, of which Figure 2 is a cross section; and,
third, of a flange U form, of which Figure 3 is a cross section. Each piece
of iron of the Figures 1 and 2 is filled up with wood of a thickness equal to the
greatest breadth of the iron. The parts marked A in each of these Figures
represent the iron, and those marked B the wood. The iron of the flange form
shewn in Figure 3 may be used with or without a filling up of wood.
Figure 4 is a side elevation of the framework of a carriage, the whole of the
parts of which consist of angle iron and wood of the form, Figure 1, with the
exception of those marked A and Bb, which are of the U form, Figure 2;
C, C, are the gushet plates by which the different pieces are united. The
pannelling is made wholly of iron plates, rivetted or screwed on to the outside
of the framework, the rivet heads or screw heads being covered with hollow
mouldings to mark the divisions between the panels. A side elevation of the
framing of a common cart, made wholly of pieces of the form, Figure 2, is
represented in Figure 5, and an end elevation of it in Figure 6. The shafts s, s,
may be either laid inside the angular corners of the framing or outside of it,
taking care in the latter case to fill up the vacant spaces and to make all
straight. The end plates E, E, the side plates F, and bottom plates G, may
be either curved in the manner shewn in the Drawings, or made straight, or
any other suitable forms, but in every case they are to be rivetted or screwed
to the inside of the framework. Instead of painting the carriage constructed
of iron in the manner described, I japan the iron either before or after the
parts are put together, the drying taking place in an oven after the usual
manner of drying japanned wares. The delay attending the customary process
of painting is thus avoided without any detriment to the exterior appearance
of the carriage, for the japanning not only admits of any degree of polish or

page_text: shade of colour which may be desired, but will not be liable to blister. The
inside finishings are fastened to the wooden portions of the framework pieces
In cases where iron framed pieces of the flanged U form (Figure 8) aro
used without any filling up of wood, the pannelling may be attached to the
flanges (h, h, Figure 3).
Secondly, my Invention consists of certain improved spring bearings for
carriages, represented in Figures 7 and 8, and also in part in Figure 4 and
Figure 10. K (Figure 7) is an iron plate which is fastened at the hinder part
underneath to the carriage body; L, L, are two cylindrical tubes, which are
attached at top to the plate K, and pass at bottom through the eyes of..a
shackle bar M', in which they are free to move up and down.
.
Each of these tubes has two spiral springs N¹, N*, slipped over it, the one
above the other, and each spring is enclosed in an outer tube O, to protect it
from dust and injury. The outer tube of the top spring N¹ is attached at top
to the plate K, and the under tube is attached at bottom to the eye piece of
the shackle bar, and the two tubes slide one within the other after the manner
of a telescope, according as they are acted on from above or below.
The top spring N' is made a good deal slighter, and consequently more
compressible than N3, so that N may not begin to be materially acted upon
till N' has been considerably compressed. With light loads the under spring
is scarcely acted upon at all, and with full loads it serves to neutralize almost
entirely the effect of the encrease of weight. The spring bar M (Figure 8)
is fastened to the spring beam which crosses the turning, or as it is technically
termed the "transmit," in the manner shewn at II in the fore part of Figure 4.
The fore-geering of the turning part is the same as in ordinary carriages, with
the exception that it is made of U iron (Figure 2). The shackle H is coupled
to the axle (as shewn in Figure 10, afterwards described), and attached at
bottom to the shackle bar M² by a pin on which it turns freely. Figure 8 is
a view of the spring bar of the fore carriage. The spring cylinders L, L, are
inserted at their upper ends into the eyes of this bar instead of into a plate K,
as in the case of the hind bar.
Thirdly, my Invention consists of two several improved modes of con-
structing the wheels of carriages. Figure 9 is a side elevation, in section, of a
wheel made according to the first of these modes; and Figure 10, a transverso
elevation of a pair of wheels, one of which is represented entire, and 'the other
in section. W is the nave; Y, the bush (shewn separately in Figure 9"),
which is cast on a mandril for the purpose of hardening the rubbing parts, or
cast soft, and then bored out and case-hardened. c, c, are recesses for holding

page_text: oil to lubricate the axle, and D is an orifice for the admission of the oil, which
is closed by a thumb-screw pin J. M, M, are flange plates of a saucer form,
which are shrunk on hot to the bush Y. N is a tube of malleable iron
which is also shrunk on hot to the inner end of the bush, but projects about
an inch and a quarter beyond it. The projecting portion of this tube (N) is
screwed inside for the purpose of receiving the screwed end of a brass nut O
(made in two halves), which is of inside diameter a little larger than the
diameter of the collar v of the axle (X), and made at its outer end four, six,
but pre-
or eight sided, to allow of the application of a screw wrench to it;
viously to inserting and screwing up the nut O a washer of leather, gutta
percha, or sulphurised caoutchouc is introduced into the bush, for the purpose
of making the latter more certainly oil-tight at this point. A nut & with
washer is also screwed on to the fore end of the axle, and the whole covered
in with a brass cap e, whereby the fore end of the axle is also made oil-tight,
and the axle secured to the wheel. The felloe is formed of a combination of
iron and wood, similar in form to that represented in Figure 2, before
described. And first, in order to obtain the iron of the required shape, I take
a piece of good iron of a length equal to the circumference of the proposed
wheel, and of a suitable thickness, say, an eighth of an inch, and pass it
between a pair of rollers, one of which has a deep groove of the U form, and
the other a projecting bead or fillet, which takes into that groove, and is of the
same form, but in reverse, simultaneously wherewith the iron is subjected to a
third roller to give it the curvature of the wheel. I then join the ends by a
short piece of iron of the same form, laid inside, which is then secured by
rivetting, and afterwards hard soldered. I next take a piece of wood of a
form and size corresponding with the hollow of the iron ring, and bring it by
steaming to such a degree of flexibility that it may be readily pressed into the
hollow of the ring without injury to the latter. I then place this compound
ring or felloe of iron and wood in a drying stove for a short time, in order to
expel any moisture which may be in the wood, after which it is then taken
out, and coated with white lead or coal tar. The felloe is then made fast to
the nave in manner following:-Instead of making use of single spokes for
the purpose, as usual, I substitute for each single spoke a double one, that is
to say, a spoke formed of two rods, the ends of which are secured to the nave,
and the other ends are welded together, and form one in the felloe. The
form of these double spokes is shewn very clearly in Figure 10. These rods
are, in the case of a five feet or four and a half feet wheel, about three-cighths
of inch iron, and for smaller or larger wheels are proportionally diminished

page_text: or encreased in diameter. At their lower ends they are passed through the
flanges of the saucer-shaped pieces M of the nave, and made fast there by
nuts n, n, between which and the iron ring a ring of leather, or gutta percha,
or sulphurized caoutchouc is interposed, in order to give greater elasticity to
this portion of the bearings. Metal washers are introduced between the nuts
and the leather, or gutta percha, or sulphurised caoutchouc rings or washers.
T, T, (Figure 10,) are circular plates of sheet iron, which serve as side
facings to the nave, and prevent the nuts from turning. The welded end
of each pair of rods is passed both through the iron and wood of the felloe,
and made fast by round nuts with broad oblong flanges a, a, which rest
upon the top of the wood, into which they are sunk flush. The periphery
of the felloe is next cased with wood of from an eight to a quarter of an inch
thick, and of width sufficient to cover both the wood and iron of the felloe, as
shewn separately in Figure 11, where i represents the iron; w, the wood; and
m, the outer wooden casing. The iron tyre is finally put on above the wooden
casing m in the usual manner. The wheel being now so far complete, is
brought up to its proper state of tension, and to a perfectly circular form by
means of the nuts n, n, and then slipped on the arm of the axle to which it is
to be applied. By combining, in the manner which has been described, iron
and wood, a wheel may be constructed, having superior qualities as to light-
ness and strength, than if it were made wholly of either material, and possess-
ing also a considerable elasticity. This form of construction offers besides great
facilities for making repairs. Supposing it is the tyre which wants repair, as
the wooden casing m is the only part which is at all injured by the putting on
of the tyre in a red hot state (the wood of the felloe beneath remaining per-
fectly untouched), it is the only part which needs to be replaced at the same
time. When again the spokes or any of then require to be replaced, this
can be readily done without disturbance to either felloe or tyre. The nuts by
which they are secured to the nave have simply to be loosened (the plates
T, T, being temporarily removed for the purpose), when the bend of the
spokes allows of their being taken altogether out of the nave, after which
they are turned round and unscrewed from the broad flanged nut, which
connects them to the felloe. And by pursuing in an inverse order the same
course of operations, the new spoke or spokes may be as effectually fixed in as
if they had formed parts of the original structure. The nuts belonging to the
nave are, for greater convenience, made all of one size and pattern, and may
be used a great many times without requiring to be replaced. The broad
flanged nuts of the felloe are never moved at all from their original places,

page_text: and will last as long as the wheel lasts. The felloe might be made entirely of
wood, and in one or more pieces, and the wheel constructed in all other
respects as before described; but I prefer the felloe composed of a combina-
tion of iron and wood as aforesaid. In the case of railway wheels, the
felloes should be made in every respect the same as those of common road
carriage wheels, and have a flanged tyre of the usual railway form. A cross
section of a felloe and tyre of this description are given in Figure 11. A
longitudinal section of a nave or boss, also suitable for railway wheels con-
structed according to my said improvements, is given in Figure 11. It
consists of a central piece of cast iron A, A, to which the two concave or
saucer-shaped pieces B, B, for the reception of the arms of the wheels, are
secured by bolts and nuts C, C.
The second mode of construction embraced under this head of my Invention
is a modification of that which has been just before described, and has for its
object the production of a noiseless wheel. In this case I dispense with the
iron tyre altogether, as also with the wooden casing on which it is shrunk, and
substitute a tyre of sea-horse leather, gutta percha, or sulphurized caoutchouc,
which I imbed in a recess made in the compound felloe before described, by
reducing the wooden part thereof. The leather tyre may be coated with tar
mixed with sand of a coarse grain, or done over first with the tar, and then
with the sand.
Fourthly and lastly, my Invention consists of a compound axle for carriages
of the construction represented in a sectional view in Figure 12 of the annexed
Drawings. I take a piece of the best plate iron, about a quarter of an inch
in thickness, four and a half inches in breadth, and of half the length of the
required axle, varying the breadth and thickness of the material according to the
strength of the axle required. I form by means of welding as much of one end
of this piece into a circular tube (say from a to b) as will suffice for one arm
of the axle, as shewn at Z; I turn this circular part in a lathe, and fit it with
a screw at its outer extremity for the reception of the nut, by which it is to be
ultimately secured to the wheel; about two inches from the inner extremity of
this circular end there is a collar V welded upon it. The remainder of the
pieco of iron, that is to say, from 6 to c, is not made circular, but of the U form
represented in Figure 2, only that the open part is placed at the bottom in-
stead of the top. I then take a second piece of iron of the same kind and
dimensions, and formed into the same shape as that just described, and weld
the two pieces together at their inner extremities, so as to form them into one.
I then insert two pieces of straight-grained wood X', X*, such as oak, ash, or

page_text: lance wood, which, at their outer ends, fit exactly the circular arm parts of the
axle, and are driven tightly into the same, and at their inner ends they are.
scarfed in the manner shewn in the sectional part of Figure 12. From the
points where the circular arms terminate on the inside of the wood is kept a
little under the edges of the U iron to allow room for the insertion of a flat
plate W, which is joined at each end to the circular arms in the manner shewn
at Z. The whole of the parts of the body or centre of the axle, that is to say,
the outer iron casing, the flat plate W, and the wooden pieces within, are then
firmly secured together by rivets r, r, passed through and through. The pieces
of wood are well coated with paint or some other suitable priming before
inserting them in their places.
And having now described the nature of my Invention, and in what manner
the same is to be performed, I declare that what I claim as the Invention
intended to be secured by the said Letters Patent is as follows:-
First, I claim the employment for the formation of the body parts of two
and four wheeled carriages of the peculiar combinations of wood and iron
firstly herein-before described, that is to say, of compound pieces of iron and
wood, of the three several forms represented in Figures 1, 2, and 3, and pieces
of iron alone, of the form, Figure 3, for the framing of such carriages, and of
japanned plates of iron for the pannelling and other parts thereof.
Second, I claim the application of japanning to carriages of iron as a sub-
stitute for painting, whether the same are japanned in the mass or japanned
in separate pieces before being put together, as aforesaid.
Third, I claim the constructing of the framework of carriages of compound
pieces. of iron and wood as aforesaid, whether the pannelling is of japanned
iron or of plain iron, or of wood or of any other material, and however such
carriages may be built in other respects.
Fourth, I claim the improved spring bearings to carriages before described,
in so far as regards the spiral springs N¹, N³, the tubes L, L, and O, O, and
the shackle H.
Fifth, I claim the several modes of constructing wheels described under the
third head of this Specification.
And, sixth, I claim the compound axle of wood and iron lastly herein-before
described.
In witness whereof, I, the said William Aitken, have hereunto set my
hand and seal, this Thirteenth day of February, in the year of our
One thousand eight hundred and forty-seven.

page_text: AND BE IT REMEMBERED, that on the Thirteenth day of February, in
the year of our Lord 1847, the aforesaid William Aitken came before our
said Lady the Queen in Her Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Enrolled the Fifteenth day of February, in the year of our Lord One
thousand eight hundred and forty-seven.