as 
C za 
the diameter of the wheel, ur reel, wilt 
require to be lessened or enlarged two 
inches in diameter for every three- 
eighths of an inch, the ropes are more or 
fess in circumference, 1 which case, the 
twist of the rope will be found tolerably 
near the twist of a hard-laid rope, and 
élose a cable-laid rope on these wheels, 
or make a shroud-laid rope of larger cir- 
eumlerence than four inches and’a half. 
The three strands may be put upon the 
nut-wheel, at the bottom end of the 
ropery, containing twenty-eight teeth; 
and the single strands upon the wheel, at 
the top end, with fifty teeth; in which 
ease the wheel, or reel, will be fixed to 
halfthe diameter of the above directions. 
If the above-mentioned proportion of 
teeth does not harden the rope, to the 
discretion of the rope-maker, the nuts at 
the top-end, with a tooth less each, will 
make the ropes harder; and with a tooth 
more cach will make them softer; and 
lessening, or enlarging the wheel, or reel, 
gives more or less twists in the rope, 
The ropes being thus made, by.a regalar 
system, will, if the spinning be well- 
done, and if the rope-maker in. getting 
the strands to the full hardness, be care- 
ful to cease twisting when the moveable 
wheel, or engine, at the bottom end of 
the ropery, Is atone and the same place 
witheach of the strands, to give the same 
hardness to all of them, and the ground 
eon which the sledge, that holds back the 
raoveable wheel, or engine, at the bottom - 
end of the ropery works, to keep. the 
strands in proper tension, be regular and 
even, be very nearly regular in twist and 
hardness, from end to ends. and for the 
eable-laid ropes, consisting geverally of 
three sinall shroud-laid ropes, or for 
makimyg fiat-ropes, all of which require 
the ropes being made to great accuracy, 
that they may all take a regular stretch 
“together, when applied to use, will be 
found a great acquisition and improve- 
ment in the strength and wear of them; 
zud im any detached shroud-laid rope 
this regulanty in the manulacturing wil] 
be found of great service. 
BIER, SAMUEL CLEGG’s, (MANCHESTER,) 
Jor a Rotatice Engine, the Piston of 
which makes a conplete Revolution al a 
Distance from the revolving ais. 
It is difficult to describe the principle 
and operation of thisinvention, without 
the aid of figures. The piston is placed 
at a distance from a valve, and an elastic 
fluid introduced by an aperture, near the 
valve, between it and the piston. The 
New Patents lately enrolled, 
[ Dec, 1, 
pistow will recede from the clastit pres- 
sure, and be earried towards the valve, 
driving before it the common air, which 
will pass off throngh an opening made 
for the purpose. As soon as the piston 
arrives atthe valve, it will push it out of 
the way, und pass onwards: and after 
the piston has passed, then the said valve 
will descend, and the pressure will con- 
tinue to operate as before, the former - 
elastic fluid passing off through the space, 
by which the common air was driven 
out, 
Observations by the Putentee—My 
invention for a rotative piston is accom- 
plished without the enormous load of 
friction that has attended other rotative 
pistons: each block, or segment, is of 
suticient weight to counteract the pres. 
sure on that part of their under-surface, 
which is over the chamber in which the 
piston revolves. The space through 
which a piston of a steam-engine, for 
twenty horses’ power, will generally be 
about twenty feet: the weight of all the 
blocks, for such a size, will be ahout fire 
hundred pounds; each block propellitig 
the bar forwards. During its descent, 
proportioned to its descending powery. 
which will be the weight of the block, 
except what is absorbed by friction, 
which suppose to be one handred pounds 
for the whole block, then it will reduce’ 
the weight of the block to be raised to 
four hundred pounds ; then, if we reckon 
the pressure upon the piston equal. to 
four thousand pounds; four thousand: 
pounds will move through the space of 
twenty feet, whilst four hundred pounds 
is raised half an inch: it will not be re- 
quisite for the blocks to be raised more 
than five-eighths of an inch for the 
largest engine, the strength of the bar 
depending upon its breadth. The flat 
facing, on which the blocks are ground, 
is about ‘three inches broad, with a 
Eroove near the centre, to introduce any 
kind of elastic packing, (if found neces. 
sary;) the one which I have at work, 
T find, keeps tight without. "The upper 
part of the blocks are covered with 
water, about three inches deep, and 
which is kept at that height. by the in- 
jection entering that part before it goes 
into the condenser; this lubricates the 
blocks, and prevents them leaking. The 
shaft which goes through the centre of 
the engine, gives motion to the aite, 
pump, bucket, steam-valve, and all the 
other requisite motions, in a very simple 
way, and being all excluded from the 
atingsphere, the inconvenience of stuf 
fing= 
