1822.] 
general combination thereof, as consti- 
tuting a machine or apparatus capable 
of being employed with advantage as a 
moving power to actuate machinery in 
general by the power of steam or water, 
or gas. 
To Mr. JOHN BARTON, 0f Silver-street, 
in the City of London, Civil Engi- 
neers for certain Improvements in 
Pistons. 
This invention is intended to dimi- 
nish friction, and secure durability ; 
and is applicable to all kinds of pistons, 
to prevent the escape of steam, air, 
water, or any other fluid, and likewise 
to prevent its escape by the piston-rod. 
The improved metallic pistons will 
be found, says the Patentee, inestimable 
in all concerns where it is an object to 
avoid delay, mines, water-works, brew- 
eries, steam-vessels, draining land, and 
in all engines and pumps where hard 
and constant work is required. In 
mines the saving of time and expense 
will be ane nint, as it will be a double 
advantage, not only in the engine, but 
in the buckets in the shafts, and will 
not require a tenth of the stoppages for 
repairs, as on the present system. In 
steam-vessels above a fourth of fuel 
will be saved, with much greater safety 
to the vessels; and where there are two 
engines, above a mile an hour will be 
gained in speed, and the fatal conse- 
quences attending explosion in a great 
measure obviated. 
To JosEPH MAIN, esq. of Bagnio- 
court, Newgate-street, London, for 
certain improvements on Wheeled 
Carriages. 
Mr. Main’s invention consists of a 
new method of attaching the body of a 
coach, chariot, gig, or other vehicle to 
its frame or carriage, by means of levers 
springs, straps, and other appendages, 
so disposed in form and position, as to 
throw the whole weight of the load into 
the centre; that is, if the vehicle be 
constructed to go upon two wheels, the 
weight of the body is thrown exactly 
into the centre between the wheels, and 
directly over the axle-tree ; if the car- 
riage have four or more wheels, the 
weight is thrown into the central point 
between the several wheels; or else 
equally divided between the central 
points between the several pairs of 
wheels. By this contrivance the erect 
and horizontal position of the body is, 
at all times, preserved, and its motions 
kept parallel to the position in which it 
was first suspended, so that, whether the 
New Patents and Mechanical Inventions. 
243 
load be placed in the centre, or on either . 
side, the body cannot hang uneven. 
To keep the body from rising to an 
inconvenient height, by sudden jolts, 
and to prevent too much strain upon 
the springs, by the load being placed 
too forward, or too backward, the lower 
part of the body is braced to the axle- 
tree, by straps from the four extreme 
corners of the under-side of the body ; 
these straps being sufficiently loose to 
admit of the several parts having their 
proper play. 
When this invention is applied to 
earriages already built, with wheels in 
the ordinary situation, and the intro- 
duction of the swivel-bar may not be 
convenient, its place is to be supplied 
hy astrong spring, crossing the carriage 
in the same direction as the swivel-bar ; 
upon the middle of this spring is to be 
placed a long spring, with its bearing- 
bar, and all the other apparatus; or | 
the long spring may he fixed upon the 
ordinary axletree; but, in this case, 
lever carriages may be attached to the 
shafts, or otherwise, as most couvenient. 
The description ahove given, relates 
only to the application of this inven- 
tion to a gig or one-horse chaise; it 
will, however, be readily perceived, 
that the same contrivance is applicable 
to other vehicles: for, supposing the 
figures represented to be carriages run- 
ning upon four wheels instead of two, 
the whole operative part of the appa- 
ratus, viz. the levers, with their sup- 
ports, the swivel-bar, the bearing-bar, 
&c. as described, would need no alter- 
ation, excepting as to strength. 
If the load is required to be disposed 
over the centres of several pairs of 
wheels, it is proposed to apply distinct 
sets of the above apparatus to each pair, 
still adhering to the principle of throw- 
ing the weight into the centre-line, 
between the wheels of the carriage, by 
which the springs will be equally acted 
upon, whether the wheels are all upon 
level ground, or any one of them ele- 
vated or depressed; by thus keeping 
the centres of gravity in the centres 
between the wheels, the risk of over- 
turning is evidently removed ; and the 
capability of traversing roads, which, 
by reason of ruts, are nearly impassable 
to ordinary carriages, is, by means of 
the close situation of the wheels, upon 
the improved principle, effected. 
The patentee, in his specification 
observes. ** in all vehicles, with two or 
more wlieels, it is desirable to throw 
the Joad, as much as possible, into the 
eentre, 
