of the oxigen in this conflagration: but I expect the expansion of the
residue (together with what _new_ vapour may be developed) will more
than compensate for that loss of volume. By this motion then, the pump
_A B_ is again filled with cold air through the valve _a_; and the
piston _E_ flying _out_ of the cylinder _C D_, the hot air it contained
_rushes_ into the pipe _o_, and thence goes to perform _any heating
operation_ that may be desired. But further, this same recession of the
piston _E_ strikes the stem of the valve _d_ against the cover _e_, and
opens that valve; by which means the large piston is at liberty to reach
again it’s _inner_ position _b_: where the bar _b_ closes it’s valve _d_
and prepares the Machine for a new stroke. For, as before, the pump or
cylinder _A B_, is full of cold air, and by the backward motion of it’s
piston exposes that air to the fire in _K_: whence arises the renewal of
all the former phenomena.
Many ideas, and doubtless some objections, will present themselves to
the readers of these pages; of which I shall probably anticipate _some_,
by noticing a few less important particulars.
And first, is it not to be feared that the vertical cylinder _K_, and
the whole system _K C D E_ will become too hot--nay acquire a red heat,
and thus introduce danger? The answer, I think, is that the fire must be
_lessened_, or the Machine enlarged, until this danger disappears: for
by heating _air_ to any thing like a _red_ heat (without attaining it)
the expansion will be _immense_: and probably beyond our wants or
wishes. The chaffing dish then (if that is used) must be lessened, that
the air from _A B_ may partly circulate _round_ it, instead of going
wholly through the fire: thus cooling the vertical cylinder _K_, and
diminishing the intensity of the heat in the working cylinder. Further,
the two cylinders _C D_ and _K_, might be inserted in the bottom of a
boiler, and surrounded with water; through which also, may be conducted
the pipe _O_, so as to concur in the same effect of heating _that_
water, while the steam thus accruing from the _double use_ of this heat,
may be made to drive an engine, heat a room, or fulfil any common
purpose.
In a word, all our difficulties on this branch of the subject, seem to
lie in _excess of action_: and we need only mitigate the general effect,
to render this Machine useful, safe, and commodious.
There is another objection that must be met, on pain of direct censure,
which is this: what will become of the ashes? (for _smoke_ is as yet out
of the question) my answer is--a recess, or several, must be found for
them beyond _o_; to do which will not be more difficult than to lodge
any other residue. But if this Machine fulfils my views in respect of
_power_, _this_ residue will be no burden. For example, if ever a farmer
should hereafter drive his _plough_ by such an engine as this, he will
manure his land furrow by furrow with the ashes--an idea which I must
not yet indulge, lest I should be thought fanciful beyond the due
proportion.
But my mechanical impetus is not to be thus instantly checked. If what I
_hope_, can be realized, there are properties in this invention, for
locomotive engines, superior to any the steam engine itself can boast. A
light Machine: a light combustible: no water to carry; no steam to
condense, &c. &c. As however I have never _tried_ this felicitous
creation, I assert nothing.
But again, this seems to be a really good method of distributing heat in
any useful direction: for there is an _impulsive force_ which not only
requires no _draught_ to make the fire burn, but will drive heat to
_any_ distance through pipes of _any_ form, and placed in _any_
position. There is therefore, a certain utility attached to this
Machine, whatever may be it’s merits as a _power engine_. Our present
methods--of destroying coals--are excellent! but our methods of making
them useful are defective in the extreme. If you have no draught in your
chimneys you are stifled with smoke. If you have much draught, you have
_little_ heat--for the chimney swallows it, and half your room is _in
Norway_. Use then an impulsive system, (of some kind) and you may _send_
your caloric down into the cellar to be _drawn_ from thence as wanted,
for the upper apartments.
But my subject pullulates as I proceed. This idea is by no means
exhausted. It is _not_ an indispensable feature of it, to heat rooms
with _the same air_ that fed the fire. For instance, if a fire were made
_under_ the vertical cylinder _K_, and led into and through it by a
proper pipe, _almost_ filling it--then the cold air of the pump _A B_
would _pass round that pipe_ to the working cylinder _C D_, and there
impel it’s piston _E_ as before. Not perhaps so strongly; but with an
air uncontaminated by burning, or by ashes--and therefore more congenial
with some uses of the Machine. In fact, air thus introduced might be
_perfectly fit for breathing_, and still get elasticity enough from this
passage, to _force_ heat to the bottom of any room we wished to have
warmed; whereas, by using only the levity of heated air to give it
motion, we scorch the tops of rooms and factories, and unmercifully
freeze the bottoms. I must beg leave to be a _little_ severe on this
point:--since for a thinking people, as strangers call us, we have been
extremely thoughtless in this respect: so that as much seems now to do
by way of introducing _comfort_ into our saloons, as was done about the
year 1200, when those chimneys were introduced that are now become a
kind of nuisance. In a word, and I am serious when I say it, the present
arrangement of our chimneys, is in my humble opinion, essentially
unphilosophical; and as such ought to be speedily discontinued or
greatly modified.
In the above pages I have laid myself open to much animadversion, by a
kind of _cast_ for much honest fame. I have let the public into my
secret--_I have thought aloud_: And if the greater part of these
cogitations should prove to be imaginary, I shall only plead, that they
are drawn from the same source as the many useful Machines I am known to
have devoted to public utility.
OF
A ROTATO-GYRATORY CHURN.
This title I confess, seems very ambitious, as applied to an utensil for
the dairy: but I had to express the combination of it’s own axis, and
those of the leaves or wings about their respective axes, while gyrating
round the common centre.
The principal shaft _A B_, fig. 8 and 9 of Plate 24, is the general
centre of rotation; and _a b_ are two lighter shafts carried round that
centre, and turning at the same time on their own centres by means of
the wheels _e f_ geering in the fixed wheel _c d_, (of which one half
only is drawn) and which forms part of the top of the churn. Each of the
shafts _a b_, carries four leaves or wings (better seen in fig. 9)
reaching from the top, nearly to the bottom of the vessel; and they run
in proper steps in the cross piece _m_, and also in proper collars in
the upper cross piece _g h_. In fine their wheels _e f_, and the fixed
wheel _c d_, which turns them, are furnished with teeth on my patent
principle; and therefore work without noise or commotion. Now, the
principal shaft _A B_, rests on the step _B_ at the bottom of the
vessel; and runs, at top, in a collar formed in the metallic bridge _i
k_, which, fixed to the outside rim of the cover, passes directly over
the centre of the Machine. When therefore, the cream is put into the
churn, (to do which the above mechanism is taken out) the mechanism is
re-placed as now represented; and the main shaft set in motion by _any
convenient power_: when the side shafts _a b_, turned by the fixed wheel
_c d_, give a backward motion to the wings _a b_, and create a great
agitation of the cream--for, it should be remarked, that this is not a
circular motion: but each fly produces a kind of vortex round it’s own
centre, while progressing round the common centre. The consequence of
which, as above intimated, is, an unceasing agitation of the liquid,
and, I believe, the best of churning. This however, I state as a
mechanician, not having been initiated into the secrets of the dairy
properly so called.
It may finally be observed, that the leaves or partitions _l n_, _fixed_
to the sides of the churn, (beyond the reach of the moveable wings _a
b_) are destined to prevent still further any _general_ motion of the
butyraceous matter; and thus to accelerate the churning process: and
further these leaves, both fixed and moveable may be pierced with holes,
like the analogous parts of other utensils of this nature.
OF
A HELICO-CENTRIFUGAL MACHINE,
_For raising Water in great quantities_.
The screw of Archimedes, is well known. When used to raise water it is
placed obliquely, in such a position as that it’s _hollow threads_
become _more_ oblique to the horizon than the axis of the screw itself:
observing which practice, some have said of this Machine, that it raises
water by letting it run down: But this cannot be true. The threads of
the screw merely _wedge_ themselves under the water, and make it _rise_
in a direction parallel to the axis of the screw; at the highest end of
which it falls into the upper reservoir.
I once placed a screw of this kind _upright_, and said (in thought) is
it then impossible to raise water by means of this screw thus placed?
The answer in a few minutes was--“not at all; there is a force would
make it easy: namely, the centrifugal force:” and this mental soliloquy
was the origin of this Invention, which, some thirty years ago, I shewed
to a public man, whom the lovers of the mechanical arts will long
remember.
In Plate 25 fig. 1, _A B_ are two screws, perfectly like those used in
exhausting watery foundations; and named of Archimedes. They are placed
perpendicularly in the frame _C D_, so as to turn in the cross bars _a
b_, _c d_, fixed horizontally on the main shaft _E F_ of the Machine. At
the bottom of this shaft, _E F_, (which turns in a step on the _sill_ _G
D_) is a low cylindrical vessel, shewn by a section only at _e f_, which
dips into the under water nearly to the brim. It is used to carry, in
proper _steps_, the centres of the screws _A B_, and, being pierced with
many holes, to feed them amply, without exposing their motion to any
resistance from the stagnant water. These cylinders _A B_ are merely
indicated as screws by the _threads_, dotted between _h_ and _d_ and _e_
and _g_, and their upper mouths are seen near _a b_, just under the
cross piece marked with these letters. These screws then, are turned by
the wheels _i k_, as actuated by the fixed wheel _m n_, in the same
manner as those of the churn before described; which in fact, is a
corollary from _this_ Machine, but of much later date. To return to the
Helico-centrifugal Machine--the screws _A B_ are terminated above by
circular plates _o p_ (marked with the same letters in fig. 2 and 3)
intended to receive the water from the mouths of the screw-threads _a
b_, and carry it _on_ to the plate _q q_, which insures it’s further
progress into the _ring canal_ _r s_, also shewn by a section only, to
prevent confusion in the figure. Now what raises the water in these
upright screws, is, it’s own _centrifugal force_, combined with the
revolution of the screws: for while this central force is urging the
water outward, the screws are bringing their sloping threads like
_wedges_, _against_ that tendency; and the consequence is, that the
water actually rises perpendicularly till it flows over the ledges or
rings _o p_, _on_ the plate _q q_, and thence into the ring canal _r s_,
from which it is conveyed to any place desired.
If this Machine is well made and proportioned, I think it is one of the
best that can be used, to do much work by a given _power_: It gives no
_shock_ to the water; which, when once in motion, continues to rise, and
escapes when arrived at it’s proper height: and, being spread over a
large surface, no part of it is raised higher than enough. The
perfection of the Machine depends on a due relation between the
centrifugal force, and the sine of the angle, which the threads of the
screw make with the horizon; and this may be modified by the diameter of
the wheels _i k_, as compared with that of the screws _A B_.
The figures 2 and 3, are two views of the upper part of the Machine.
They shew, and mark with the same letters, the cross bar _a b_, the
inside of the screws, and the circular plates _o p_, together with the
circular conducting plate of which _q q_, fig. 1, is the section. Fig. 3
shews the fixed wheel _m n_, the two screw-wheels _i k_, the cross piece
_a b_, and under them the plates _o p_ of the 1st. and 2d. figure.
One other object claims our attention: The threads of the screws
(whether more or less numerous) should each be furnished with a valve at
bottom: that the water may _not_ run out when the Machine ceases
working.
OF
A FORGING MACHINE,
_For Bar Iron, Steel, &c. square or figured_.
This Machine acts by pressure instead of percussion. But this pressure
is so instantaneous as to resemble a blow, and so often repeated as to
produce a considerable effect in a short time. The means are represented
in fig. 4 of Plate 25.
There, _A_ is a mass of metal answering the purpose of an anvil, but
having two surfaces, situated at or nearly at right angles to each
other, on which the metal is alternately struck or compressed. The two
sides of this mass _A_, are perforated by two holes, properly _bushed_,
in which turn the crank shafts _B_, _C_: the latter furnished with the
bevil wheels _D_, _E_, which geer into and receive motion from two
_equal_ bevil wheels _F_, _G_, fixed on the main shaft _H I_, and to
which the power is applied. It is thus evident that the two crank shafts
_B_, _C_, will make the same number of revolutions; and that if one of
the rollers _K_, _L_, is placed on the excentric arm of one shaft, and
the other roller on the other (their position being as in the figure)
that then the rollers _K L_ will impinge alternately on any bar, held in
the angle _M_, and forge or extend it, and finally leave it reduced to
the same dimensions, in it’s whole length, if, by hand or proper
machinery, the bar has been drawn or pushed along the angle _M_, in a
manner analogous to this motion at the tilt hammer. It is also clear,
that the size of the bar will be determined on a given Machine, by the
diameters of the rollers _K L_, compared with the distance of the shafts
from the angle _M_ of the anvil.
It may be of use to observe, that the effect of this Machine is not
confined to square bars: since with unequal rollers _K L_, it will
produce flat bars; and with rollers properly grooved, (the piece _M_
being formed accordingly) it will produce round iron or steel of better
texture (I presume) than when taken from the slitting-mill, and merely
passed through grooved rollers. I expect, at all events, a _rapid_
effect, from four or five hundred turns of the cranks per minute.
It will occur to every mechanical reader, that the mass _M_, which is
tempered and adjusted to the principal anvil _A_, may be still more
varied in form, so as to give other results besides those above
anticipated. Nor need it be said, that the shafts _B C_ might run in
steps capable of being _screwed up to their work_, even during the
process, should any such motion be expedient. These are details I do not
wish to dwell on in these descriptions--where I endeavour to make known
general and essential properties, leaving particular views and cases to
my reflecting readers.
OF
A RECIPROCATING HORSE WHEEL,
_For Mines, Mangles, &c._
I believe there is no better floor for a working horse to tread on, than
a plane of wood--on condition, of the horse being rough shod: I speak
however, on recollection of many years’ standing. I then felt persuaded
that a horse wastes less effort by travelling on _this_ floor than on
any other; which is one of my reasons for the adoption of the present
Machine. It consists (Plate 26, fig. 1,) of a wheel _A B_, on which the
horse walks, as indicated by the sketch of him given in the figure.
Besides this, he is placed between two shafts _C D_, affixed to the
lever _E F_, the latter carrying round with it, at intervals, the drum
_G_, whose office it is to raise the weight _I_, whatever kind of
resistance that weight represents. This lever runs by means of it’s
_cannon_ _L_, on a round part of the shaft common to it and to the drum
_G_. Moreover, there is a second drum _H_, destined to raise the weight
_K_, whatever kind of resistance _that_ represents. Both the drums, _G_
and _H_, turn on round parts of the main shaft _M_, but are alternately
connected with it--first, the drum _G_, by the rising of the bolt _a_
into it; and secondly, the drum _H_, by the falling of the cross piece
_b c_, between the studs _e d_ affixed to it. Now, this cross piece _b
c_, is part of a T-formed bar, that penetrates the centre of the shaft
as low as _f_, where it rests on a transverse lever _f g_, connected _to
the right_ with the bolt _a_ above mentioned, and forming a branch of
the bent lever _f g h_, which works the bolt _h i_ under the wheel. In
the present state of things, if the horse steps forward, he draws the
shafts _C D_, round the common centre; for the wheel is immoveable by
means of the bolt _i_, which _takes_ against some fixed object at _k_:
and thus will the weight _I_ be raised. And when this motion is
achieved, the handle _o_ is raised a few inches, which brings it into
contact with the obstacle _p_, and puts a stop to that motion of the
lever _E F_. At the same time the bolt _a_, is drawn out of the drum
_G_, and the cross piece _b c_ is let down between the studs of the drum
_H_, while, by the bent lever _f g h_, the bolt _h i_, which held the
wheel, is drawn back, and _then_ the horse, instead of progressing round
the centre of the wheel, is himself brought locally, to a stand; and
without even knowing it, (for he is blinded) he now treads round the
wheel in a backward direction, and raises the weight _K_, while the drum
_G_ permits the weight _I_ to descend by the uncoiling of the rope, till
_this_ operation has likewise produced the desired effect--when things
are again placed in the state first observed. One thing remains to be
noticed: It is, that both these motions _might_ have been produced by
acting from a fixed point on the central bar _b c f_, through the upper
gudgeon of the shaft, _instead_ of using the handle _o_, as before
directed. It is even easy to conceive how the Machine may itself be made
to perform these changes, and thus to produce the whole effect without
any personal care or attendance.
OF
AN EXPANDING VESSEL,
_For Steam Engines, Pumps, Blowing Machines, &c._
It is one of the simplest and most perfect operations of the mechanic
art, to form a _flat surface_: witness the process of grinding looking
glasses, and forming one plane from another. Nor is it, necessarily,
more difficult to place two surfaces parallel to each other, by means of
three or more _pillars_ with proper shoulders, or counternuts against
which to screw the plates from behind. It is therefore easy to compose
an expanding and contracting vessel, that shall become _a mover_ by the
force of any fluid, elastic or not, or shall act as a water or air pump,
when driven by a convenient power; or both together, when this
combination may be desirable. Thus, in Plate 26, fig. 2 and 3, _A B C D_
is a box with four sides and four _jointed angles_--which, if one of
it’s sides, _D A_, be fixed to a given position in the cage or frame _E
F G H_, will expand or contract according as the sides _A B_ and _D C_
shall rise toward the perpendicular, or fall toward the horizontal
position. The dotted lines _A_ 2, _A_ 4, _A_ 6, &c. shew that the
successive capacities included in the vessel, are respectively as the
sines of the angles which those sides _A B_ and _D C_ make with the
horizon; so that, although this device furnishes an _unequable_ power,
yet it is equable enough for many purposes in the first few divisions
_D_ 3, _D_ 5, &c. and might be altogether _equalized_ in it’s effect if
necessary. Let us suppose then, that the aperture 8, brings steam into
this vessel: The _lid_ _B C_ will rise to 6, 7, when, if the pipe 9,
communicating with a condenser, be opened, the steam in the vessel will
rush thither and be destroyed: when the atmosphere will press on the lid
_B C_, and cause the vessel to collapse with a power proportionate to
that area; for the sloping and parallel sides _A B_ and _C D_
counterpoise each other; where note, on occasion of the _pressure_ which
I am now speaking of, that the ribs or bars _L M_, are used to
strengthen the sides of the vessel, and thus prevent it’s fracture under
this pressure.
From this manner of making these expanding vessels, it follows among
other things, that if the frame _E F G H_ were surrounded with wood or
any non-conducting substance, and made to communicate with a warm close
room, the atmosphere thus acting on the vessel would _not_ cool it, and
that therefore, an atmospheric engine, would, in this respect, be as
good as a steam-acting one. But steam might be introduced into this
outer case, and act as a spring to reciprocate the internal effect of
the same agent.
The third figure of Plate 26, offers an end view of this cage or frame,
shewing the expanding vessel at _B C A D_, where the strengthening ribs
of fig. 2 are seen _endwise_ at 1, 3, 5, 7, &c. and moreover, _F G_ and
_H_ are the pillars or cross bars by which the parallelism of the two
end plates is effected and secured.
There remains an important subject to be considered: How to make the
corner joints _D C_, and the end joints steam or water-tight as
required. The small figure 4 answers the question as far as _water_ is
concerned. _A_ is a strip of leather screwed more or less near to the
_edges_ of two contiguous sides of the vessel, so as to cover the joint
or hinge, and make it water tight whether the pressure come from within
or without. This figure also shews the grooves which receive the
stuffing to close the _ends_ of the vessel, by sliding against the
plates or cheeks _E F_, &c. fig. 2. The several members of the corner
joints themselves should be well fitted into each other: so indeed as
almost to close the vessel without _any_ stuffing. Nor need we in all
cases be anxious about this stuffing; for I think it very possible to
make this joint close enough for pumping or blowing without any such
provision. I observe, however, that the leather _A_, fig. 4, might give
place to a strip of thin metal, bent into the same form, (or nearly so)
the elasticity of which would leave play enough for the joints, on the
supposition of working only with a moderate degree of motion in the said
joints.
I should not have given this idea so much attention, had I merely wished
to use it where the cylinder-motion now applies: But my present views go
further. I foresee the use of this Machine for _very low_
pressures--and in _very large_ dimensions; and I can conceive a
proportion between it’s length and height, that shall as it were annul
the effects of friction and leakage, compared with those of the
cylinder-formed piston. But I do not undertake, or hardly wish _now_, to
exhaust this subject: being more anxious to _deliver_ the idea to my
readers, than to announce all I intend to undertake by it’s means. I
shall, therefore, merely finish the description of the other figures 5
and 6 of this Plate. The first, is a small hand pump on this principle,
having a suction pipe _A_, and a rising pipe _B_, both having proper
valves and opening into the expanding vessel, as _worked_ by the handle
_C_, much in the manner of a common pump. It will therefore act by it’s
expansive and contractile properties; and have one good quality we
should seek in vain elsewhere--It will _begin_ the motion of the water
with a _softness_ unknown in the use of pumps in general.
In fine, the sixth figure shews a System of this kind applied to the two
objects, of _giving_ power, and _using_ it. The vessel _A B_, receives
the power from steam or any other agent; and the vessel _C_ blows a
fire, raises water, or does any analogous work, without requiring any
other _parts_ than those here displayed.
OF
A GOVERNOR, OR REGULATOR,
_For Wind-Mills, Water Mills, Steam Engines, &c._