i ie 
-able, without the help of figures. 
1811.] 
Cts): 
PATENTS LATELY ENROLLED. 
SS 
MR, THOMAS MEAD’s, (SCOTT-STREET, 
orksurre,) for Methods of Making 
lircular or Rotative Steam Engines, 
upon an entire new Principle. 
3 Saas principle of this invention is not 
confined to enginesof any particular 
form, but it consists in making use of 
two moveable pistons in such a manner 
that they alternately revolve, or move 
round their axes or centres, as we shall 
endeavour to explain, as well as we are 
There 
are two circular plates or shells of metal, 
similar in their construction, having their 
-insides made very correct. Each of these 
circular plates or shells, has a flanch 
and semicircular cavity formed for the 
reception of the pistons, which are af- 
terwards described, and a recess or hol- 
~ Jow part formed round its centre, fora 
small circular plate to turn in. Near 
the edge of each recess is a small groove 
running quite round; in the bottom of 
each groove is placed a metallic ring, and 
the remaining part of the groove is fitted 
up with packing or wadding, which ring 
and wadding may be moved with screws 
‘going through each shell, and may be 
turned on the outside of the engine after 
itis put together atany time, to make the 
small circular plates work steam-tight. 
On the outside of each shell, at its cen- 
tre, is a hollow pipe for the reception of 
spindles. One of the circular plates has 
two holes, to which pipes are fitted, one 
to convey steam into the shells, the other 
to conduct it from them into a condenser 
wherever it may be required. The figures 
attached to this specification exhibit the 
parts already described, and also two 
pistons with grooves round them, to ad- 
mit of a wadding and two small circular 
plates, to which the pistons are con- 
nected, or made fast... One of the spindles 
referred to is made hollow, to receive the 
other, which is solid, and passes through 
it. Two arms are fastened to the spin- 
dies, and each arm near its extremity 
carries a wheel, called a friction-wheel; 
a fly or regulating wheel, fixed to one end 
of a moveable axis, having in its front, 
Opposite to its axis, a groove ruuning 
across its diameter, for the reception of 
the friction-wheels, which wheels, when 
the pistons are putin motion, work in it, 
and give motion to. the fly-wheel, and 
‘other machivery which may be con- 
nected with it. All the parts being de« 
scribed and shewn in the drawings, we 
are told; when the engine is to be put 
together, the arms should be taken from 
the spindles, and the solid one fixed into 
that which is hollow, which, with their 
respective pistons, and small circular 
plates, are to be placed in one of the shells, 
and the other placed over them: the 
shells are then to be fastened together, 
with screws or otherwise, so as just to ad- 
mit the pistons with their respective 
plates and spindles to turn round in their 
respective chambers nearly steam-tight ; 
the arms may then be made fast on the 
spindles, and the engine erected. Di- 
rections are now given for fixing the ma- 
chine, which being done, and ready to 
be set to work, the steam is permitted to 
enter by one of the pipes into the steam. 
cliamber, where, by its elasticity, it wilt 
‘press or act upon both pistons nearly 
alike ; and, as one of the pistons is stop- 
ped or held fast, the steam cannot pass 
into the other pipe that way, but will 
force the other piston round with its small 
circular plate, spindle, arm, and friction- 
wheel, and put the fly in motion, and 
continue it. A similar effect may be 
produced with a concave globe, or sphere, 
having within it two moveable ‘semicire 
cular leaves, as substitutes forthe pis- 
tons, with packings at their edges, and 
united in the centre or axis of the eloba 
with hinges, and having each of them 
an axis passing through the globe to 
receive the arms and. friction-wheels, 
and with holes, pipes, &c. for the admis- 
sion of steam. Engines on this principle 
may be made of every size, and may be 
put in motion by air or ‘water as well as 
steam. The invention may be applied 
to engines for extinguishing fire, or for 
raising or forcing water to any height, 
and for other purposes of practical utie 
lity. 
—E 
MR. EDWARD SHORTER’S, (WAPPING,) 
Sor an Apparatus for Working Pumps. 
_ Mr Shorter, in) describing his inven- 
tion, says, he fixes at the stern or after- 
part of a vessel, an -axis‘nearly parallel 
to the horizon, and in a fore and aft die 
rection, so that one of ‘its extremities’ 
may be within boardyand the other, viz, 
the aftermost extremity, shall either be 
without board, or so placed as to admit of 
the fixing of an external apparatus on it, 
intended to produce a rotatory motion in 
the said axis, by means of which the 
pump or pumps of any description may 
he 
