CERTAIN IMPROVEMENTS ON WHEELED CARRIAGES
Year: 1820

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
MAIN,. of Bagnio Court, Newgate Street, in the City of London, Gentleman,
send greeting.
WHEREAS His most Excellent Majesty King George the Fourth did,
by His Letters Patent under the Great Seal of that part of the United
Kingdom of Great Britain and Ireland called England, bearing date at West-
minster, the Twentieth day of October, in the second year of His reign,
give and grant unto me, the said Joseph Main, my exors, admors, and
assigns, His especial licence, full power, sole privilege and authority, that
I, the said Joseph Main, my exors, adiñiors, and assigns, during the term of
years therein mentioned, should and lawfully might make, use, exercise, and
vend, within England, Wales, and the Town of Berwick-upon-Tweed, my
Invention of "CERTAIN IMPROVEMENTS ON WHEELED CARRIAGES;" in which
said Letters Patent there is contained a proviso that if I, the said Joseph
Main, shall not particularly describe and ascertain the nature of my said
Invention, and in what manner the same is to be performed, by an instrument
in writing under my hand and seal, and cause the same to be inrolled in. His
Majesty's High Court of Chancery within six calendar months next and
immediately after the date of the said Letters Patent, that then the said
Letters Patent, and all liberties and advantages whatsoever thereby granted,
shall utterly cease, determine, and become void, as in and by the same
(relation being thereunto had) will more fully and at large appear.
"
NOW KNOW YE, that in compliance with the said proviso, I, the said

page_text: Joseph Main, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, are particularly described
and ascertained in and by the Drawings hereunto annexed, and the following
description thereof (that is to say) :-
That as the body of the carriage, or that which contains the persons or other
load to be carried, is called or distinguished by coachmakers simply as the
body, and the framework, shafts, and other parts to which the axletrees and
wheels are attached is also by them called the carriage, I shall for simplicity
sake, in my description, adopt the same language; consequently when the word
carriage alone is used I mean it to denote such framework, with the axletrees,
wheels, shafts, and other usual appendages, while by the word body I denote
that part only which is to contain the load; and when the carriage and body or
compleat vehicle is intended to be expressed I use either the proper name,
coach, chariot, gig, and so on, which applies to the particular kind of vehicle
alluded to; or else, when the principles I am about to explain apply equally to
every species of carriage, I use the general term vehicle. Thus much pre-
.mised, I hereby declare that the principal of my Invention consists in attaching
.the body to the carriage by means of certain springs, levers, straps, shackles,
and other well-known apparatus, so altered and disposed in form and situation
as to throw the whole weight of the load into such situation as may be most
desirable, according to the construction of the vehicle. Thus in vehicles with
two wheels I throw the whole weight of the body exactly into the centre, or
.half way between such two wheels and directly over the axletree. In vehicles
with four or more wheels I throw its weight on to a line drawn in the center
between the wheels, and either into the central point between the wheels or
else (still keeping it on the same line) I divide it equally over the several
pairs of wheels or proportionably among them, according to their respective
sizes; and at the same time my Invention secures the horizontal position of the
body, and causes all its motions to be parallel to its first situation, so that
whether the load. be in the center or on either side of the body it cannot get
into an oblique position, which I consider to be of great importance, since on
the present general construction of vehicles a heavy person getting into the
body from one of its sides is sure to depress that side very considerably. The
manner in which these several advantages and improvements are brought
about and produced will, however, be more evident on inspecting the Drawing,
in which Fig. 1 represents a side view, and Fig. 2 a plan or view from above
of a gig or one-horse chaise, having two wheels; and mounted or hung upon
my said improved principle. The same letters of reference are used in both
these Figures to denote the same parts wherever they occur in them both, and

page_text: the body is supposed to be removed or taken off in Fig. 2 to shew the form
and disposition of the levers, springs, rollers, and other apparatus which are
placed beneath it. Its situation when fixed is, however, indicated by the dotted
lines A, A, A, A, which shew the form, extent; and situation of its bottom or
platform. The wheel nearest the eye is likewise supposed to be removed in
Fig. 1 to shew the springs, levers, and other parts more particularly. The
body, together with its several springs, levers, and supporters, rest entirely upon
the cranked or bent piece of iron, steel, or other sufficiently strong metal or
other material, which I call the swivel bar, shewn separately at Fig. 3, and
also shewn as bung in its proper place by means of its two pivots or bearings
B, B, in all the said Figures; or. it may be then fixed without pivots and
bearings if made as herein-after is directed. These pivots turn in brass or
other bearings fixed upon the shafts of the gig, which are made and shaped in
the ordinary way, as indicated by the letters C, C, Figs. 1 and 2. The lower
part D of the swivel bar Fig. 3 hangs downwards, as shewn in Figure 1, and in
the central part of it, midway between the two wheels, I attach the long spring
E, E, curving upwards and firmly to it by straps, bolts, and nuts, or other
usual means, in such manner that this spring may be at right angles to it, or
parallel to the wheels, as will be seen at E, E, Fig. 2. This spring may
be made in one piece or in separate leaves, as is usual in carriage springs, but
must be of such strength as to bear the weight of the body with its load and all
its various levers and appendages, without bending home or ceasing to act as a
spring. Immediately over this spring I apply a 'straight bar of iron or steel,
which I call the bearing bar, and which is shewn at F, G, Figures 1 and 2.
This bar must be strong enough to bear the entire load without bending, or
else may be a strong spring, and one end of it, as at F, is attached to one end
of the spring E, E, while the other end is supported by a swivel, or moves upon,
a friction roller applied to the other end of the spring, immediately under G.
The use of this roller or swivel is to prevent friction when the spring E, E,
opens in consequence of any pressure on the bearing bar, which must be so
long as not to quit this roller when the spring is opened to its fullest extent.
It is not material which end of the bearing bar is fixed to the spring so long
as that fixture and the roller or swivel are at opposite ends. I next apply
two levers across the bearing bar and spring, and at right angles to them, as
will be seen most distinctly at H and I, Fig. 2, although their situations are
likewise indicated by the same letters in Fig. 1. These levers have long or
extended pivots or fulcra K; K, Figure 2, to render their motion steady and
free from shake, and they turn or move in bearings or carriages fitted to them
on opposite sides of the carriage as near the wheels as may be safe and con-

page_text: venient, the bearing or carriage of the lever H being shewn at L, L, in Fig. 1,
and both of them at L, L, and M, M, in Fig. 2. These bearings or car-
riages L, L, and M, M, are firmly fixed to the two descending arms of the
swivel bar, Fig. 3, in such situations and at such height as to permit the two
ends of the levers H and I, which are furthest from their fulcra, to assume the
elevated positions shewn by H and I in Fig. 3, while the middles of such
levers rest by their own weight upon the bearing bar F.
. Lastly, the two elevated ends of the levers before-mentioned are let into or
otherwise attached to the cross metal pieces N, N, and 0, 0, which stand at
right angles to them, as more particularly shewn in Fig. 2, since only one of
such pieces N, N, can be seen in Fig. 1. These last-mentioned pieces are
elongated for the reasons before-mentioned, viz, to avoid shake and produce
equality of bearing and steady motion. Each end of these pieces is furnished
with pivots that fit into holes in the pieces P, P, P, P, which are screwed to
the under side of the bottom or platform of the body. The pivots of one of the
cross pieces, as 0, 0, simply fit into the holes in the pieces P, P, which are shewn
next to it, but the pivots of the other cross piece N, N, must be connected with
its screwing pieces P, P, through the medium of swivels or shackles, as will
be more distinctly seen at P, P, Fig. 1. These become necessary to admit of
the varying effective length of the levers H and I, as they are more or less
pressed downwards by the weight in the body. The levers H and I are
cranked or bent into the form shewn at Q, Q, Fig. 3, to admit of these swivels
and bars descending lower than they could otherwise do in violent motions of
the carriage. From the above description it will appear that whether the load
be placed on one side or the other of the body, it is, by my Invention, transferred
to the centre; as, for example, if a person be supposed to be sitting on the off-
side of the body, or over the bar marked N, N, Fig. 2, in the ordinary mode
of hanging, that side of the body would be depressed, and more weight would
be thrown upon the wheel R than upon the opposite one S, which has a
great tendency to overturn the vehicle; but in my construction such a load
could not depress the bar N, N, without lowering the lever I, and this could
not sink without lowering the bearing bar F, G; and whenever this is
lowered the lever H, and with it the cross bar O, O, would loose its support
and be lowered in an equal degree, so that the whole pressure of the load is
carried to the bearing bar F, G, which is in the center, and all the up
and down motions of the body must be parallel to each other. By this
transferring the entire weight of the load to the central part between the two
wheels, I am enabled to place the wheels much nearer together than can, be
done in any other mode of hanging bodies, without increasing the risk of their

page_text: being overturned. I have illustrated this in the Drawings above referred to,
by placing the wheels within instead of without the shafts, which in some
situations will be attended with advantage, as in bad roads it will enable a
vehicle on my construction to run within the ruts, when another vehicle of a
light description would be incapable of running at all. The iron wheel
brackets T, T, which are fixed under the shafts in the usual way, will be the
same (except as to the distance of their bows from the shaft) whether an
ordinary axletree and pair of wheels are used on the outside, or whether the
wheels are fixed in the inside, as indicated in the Drawing; but when inside
wheels are used I prefer making the axletree a fixture to one of the wheels,
and letting it revolve with that wheel while the opposite wheel is loose and
capable of revolving upon it, which gives great convenience in turning, and when
the axletree is so made to turn round as aforesaid, I make its shape similar to
the section shewn at Fig. 4, one great object of which is to obtain the end
bearings V, V, which from their shape, and their end caps oversailing the
boxes in which they run, will effectually act as a brace, and prevent the wheel
brackets T, T, from spreading or getting out of their proper situations. W,
Fig. 2, shews an oil box or reservoir, which may be placed over the bearings
when on this construction. I shall now describe the several bracings that are
necessary to keep the body hung as before in its proper situation, which are
but few in number. In the first place, if the swivel bar hangs on pivots, as
shewn at Figure 3, and already described, which mode of hanging is adopted
to take off the up and down motion of the horse, and to preserve the horizontal
position of the body, it will be necessary to apply a brace spring or springs on
one or both sides of that swivel bar or iron, as shewn at X, Y, in Figures
1 and 2, for the purpose of preventing its getting into an oscillating motion.
Two pair of spiral springs pulling in opposite directions are shewn at Figure 2
in the Drawing, but it will be evident to any mechanic that one spring or a
single pair of springs, as X, X, only, will answer the purpose, if they are of
such construction as to be capable of contraction and expansion, or of acting
both ways; and the same effect may likewise be produced by making the
springs themselves part of the swivel bar, for if the descending parts of this bar
from B to a, Fig. 3, be made springs either of flat steel plates in leaves or
otherwise this will answer the same purpose, and in this case this bar must not
have the pivots B, B, at its upper ends, but these ends must be spread out and
firmly attached to the shafts by bolts and nuts, screws, or other means.
swivel bar prevents the necessity of having any spring in the shafts, conse-
quently they may be made of a stronger and more serviceable form than
usual, and the manner and situations in which springs may be applied to this
The

page_text: bar to produce the effect above mentioned are so numerous, that it would be
in vain to attempt the description of all of them. When, however, my Invention
is applied to vehicles already built with external wheels in the ordinary
situation, and the introduction of the swivel bar may not be convenient,
(though I always prefer it when it can be adopted for two-wheel vehicles), I
supply its place by a strong spring placed or hung across the carriage in the
situation of the bottom part D of that bar, and upon the middle of that spring
I place and fix my spring E, E, with its bearing bar, and all the before-
described apparatus; or the spring E, E, may be fixed upon the ordinary
axletree, but in this case the lever carriages L, L, M, M, instead of being
fixed to the springs or other perpendicular sides of the swivel bar, is already
described, must be fixed to the shafts or upon blocking pieces above or below
them, as may be most convenient, or in some other strong and convenient
manner, which it is impossible to describe, inasmuch as it must depend
upon the form and construction of the carriage, and will be easily
contrived by any competent mechanic. Lastly, to keep the body from
rising to an inconvenient height by sudden jolts and inequalities of the
road, and to prevent too much strain upon the spring or springs of the
swivel bar by the load being placed either too forward or too much in the
rear, I tie or attach the lower part of the body down to the axletree
by means of four leather straps or braces, the upper ends of which are
buckled or otherwise affixed to the four extreme corners of the under side of
the body, while their lower ends pass through two rings slipped on to the
axletrees, as may be seen at Z, Z, Figure 1. These leather braces must be
sufficiently loose to admit of the play of the several levers, springs, and bearing
bar without permitting the body to rise to such a height as night be
productive of inconvenience.
Having thus described the nature of my Invention, and the manner in
which it may be applied to a gig or one-horse chaise, it will readily appear
how it is applicable to other vehicles; for if the carriage represented in Figures
1 and 2 be supposed to have four instead of two wheels, the whole effective
parts of my apparatus which I claim as my Invention, viz, the levers with their
carriages, the swivel bar and bearing bar, and their several bearings, and the
application of the springs, pivots, and swivels, as before described, would stand
in no need of alteration unless for greater strength, or to produce another
disposition of the load upon the wheels, the same apparatus as above
described were to be repeated, and one set of it placed over each pair of
wheels, which in some cases may be necessary, no other alteration would be
required; but it will be evident to any mechanic that by disposing the appa-

page_text: ratus in different situations the load may be divided or dispersed over any
number of wheels in any proportion that may be desirable, still, however,
keeping it so immediately over the central line of the carriage that the springs
will be equally acted upon whether each opposite wheel is on level ground
or the one elevated above the other, and by thus constantly keeping the center
of gravity evenly between the wheels the security from overturning of vehicles
on my construction will be evident, as well as their ability to pass where others
cannot, because from this circumstance the wheels may be placed much nearer
together than on any other construction. In all vehicles with two or more
wheels it is desirable to throw the load as much as possible into the centre
between those wheels, and therefore in the above description I have endea-
voured to show how effectually this may be done by my aforesaid Invention.
But in some cases it may be necessary to bring the pressure of the load as
low down as possible, and to equalize it between the two sides of the carriage
so as to cause one to balance the other. This is particularly the case in the
attempts that have been made to construct vehicles with one wheel only, in
which there is nothing to maintain the erect position of the vehicle but the
attachment of the shafts to the horse's body, and preserving as correct an
equilibrium as possible on either side of the wheel. My invention of cross
beams is particularly applicable to this purpose, and therefore in Figs. 5 and
6 of the annexed Drawing I give an example of the manner in which they
may be so applied, even without the intervention of a bearing bar. Fig. 5
is a perspective view of a gig of the above description, having but one wheel,
and Fig. 6 is an elevation of the same, as seen from behind. The same letters
of reference being used in both these Figures, from the similarity of the parts
in this vehicle to those already described, it will not be necessary to go into a
minute description of them, and I shall therefore merely repeat their names,
unless when any difference of construction occurs. 6, b, is the carriage frame
and shafts. c, c, the wheel brackets or blockings fixed below them. d, the
axletree turning with the wheel e, and having end bearings to prevent the
wheel brackets or blockings from spreading, as spoken of when describing
Fig. 4. ff, two springs of the usual construction firmly fixed at their
lower extremities to the wheel brackets immediately over the axletree. The
upper ends of these springs carry friction rollers as at g, g, upon which the
two levers h, i, rest. k, k, the fulcra or elongated pivots upon which these
levers turn iu metal cheeks 1, 1, placed within the wheel brackets. The oppositė
ends of these levers are equiped with cross pieces m and n, similar to those
already described, and the pivots of these cross pieces fit into holes in the
studs o, p, which are fixed to the under side of the body q, r, the cross piece m

page_text: merely fitting into the holes of o, while the pivots of a are attached to p by
swivels or shackles, as before mentioned, to admit of the varying length of the
levers h and i, as they are more or less pressed downwards. The operation
of this arrangement of springs and levers will be most evident on inspecting
Fig. 6, for if a load be supposed to be placed over r in the body. its tendency
would be to produce an overturn by bringing that side to the ground, but the
weight on r will be over m, and by means of the lever h is transferred to the
bottom s of the spring f, close to the axletree, and may even be brought lower
if required, consequently, it acts on the contrary side to that which it is really
placed, and is removed from an high to a low situation, and therefore produces
the best effect which can be expected in a vehicle of this description.
In describing the above principles of my Invention it is impossible for me,
either by description or drawing, to give all the various forms, curves, shapes,
and dimensions of the several parts above enumerated, many of which must
depend upon the taste of the maker, while their strength must be suited to
the vehicle in which they are employed, and the load or number of persons
it is to carry. In my said Invention I do not therefore confine myself to the
forms of the parts shewn in the Drawing, but to the mode of hanging the
bodies. of vehicles upon cross levers, either with or without a bearing bar,
and with or without a swivel bar, or with its substitution of a cross spring,
as herein-before described.,
In witness whereof, I, the said Joseph Main, have hereunto set my hand
and cool this Twentieth day of Anril in the roar of our Land One