the other the descending pipe _C D_. They are surmounted by two
cylinders, of unequal capacities--this inequality bearing a given
proportion to the difference in the heights of the rising and falling
branches of the Syphon. In each of the cylinders works a piston _a_,
_b_, which, I think, need not be stuffed, but _well_ fitted. The large
piston has proper valves in it, to let the water pass upwards, at all
times; and the small piston has a valve _i_, opening upwards, by means
of the mechanism we are now describing; and closing itself merely by
the arrival of the piston into it’s present position; for the screw _c_
prevents the valve from rising higher: _e_, _f_, are two arcs belonging
to the lever _E_, and being circles round it’s centre of motion. They
are cut into teeth, on my Patent principle, and work in the racks
similarly _toothed_, which give motion to the pistons _a b_, or receive
it from them. Further, behind the stand _F_, common to both levers,
vibrates, on a pin, another lever _g h_, the use of which is to _work_
the aforesaid valve _i_ in the small piston; and this it does, by means
of the weight _h_, in the following manner:--The machine being supposed
in the present state, the Syphon will act, as usual, through the valves
of the large piston; and the water pressing on the small one, with a
power proportionate to the excess of it’s column over that of the other
piston (_a_), will raise the latter as fast as the piston _b_ descends;
but the area of the piston _a_ being _larger_ than that of the piston
_b_, there will be a pressure within the vessel _b c d a_, that _must_
expel (through any prepared aperture at the top) a quantity of water
equal to the difference of area between the two pistons, multiplied by
the stroke of both: the real quantity of which will ultimately depend on
the difference of level between the higher and lower water; or between
the lengths of the rising and falling branches of the Syphon, _B_ and
_C_. When, therefore, this stroke is made, the end _h_ of the lever _g
h_, which carries the ball, will touch the screw _d_, and stop the
descent of the valve _i_, which will thus be opened; when the water will
have free egress through the descending pipe _C_, and the piston _b_
will then rise through that water by the weight of the piston _a_, the
valve _i_ being _kept open_ by the action of the weight _h_, until the
piston _b_ has risen to it’s present position, when a new stroke is
prepared, for the same reason as before: and thus may water be carried
over a hill of (about) 30 feet above the level of any stream or pond,
and dropped into a _lower_ canal on the other side, with the condition
of leaving a part of that water upon the hill, proportionate to the
difference between the level from which the water is brought, and _that_
to which it is carried.
OF
A FORCING MACHINE,
_For taking on and off the Cylinders of Calico Printers_.
The two figures, 1 and 2, of Plate 30, are intended to make this Machine
known, assisted by the following description:--The first is a front view
of it, and the other a partial view from above. In the former, _A B_ is
the frame formed of, and firmly connected with the two columns _C D_,
which are fixed strongly to the ground, at such a distance below the
ends _C D_, as to place the aforesaid frame at the height of about two
feet, or higher, if convenient.
In the two cheeks of the frame _A B_, are cast or bored two round holes
for receiving the gudgeons of the _swivel_ _E_, one of which gudgeons is
also seen at _E_, in fig. 2. This swivel turns in these holes; and it is
itself perforated with a round hole just large enough to receive freely
the body of the mandrel _F G_. This mandrel has now on it the cylinder,
which is to be taken off. _I K_ are, moreover, two ears or studs cast or
welded on to the top and bottom of the said frame _A B_, and at exactly
the same distance from the centres of the swivel _E_ before-mentioned.
These _ears_ receive the ring-formed ends of the bars _L M_; see also
the bar _L_, in fig. 2. To these bars is firmly fixed the cross-bar _N
O_, which forms the _nut_ of the screw _P_, by means of which the
operation of the machine is duly _prepared_; for, now the cup _Q_ (in
the centre of which the screw _P_ revolves against a proper shoulder)
receives the end _G_ of the mandrel, which it presses forcibly, while
the whole is in the position _E L_, of fig. 2; that is, when the two
centres _E_ and _R_ form one right line with the bar _L_, figs. 1 and 2.
To complete, then, the process of driving out the mandrel, the bars,
mandrel and cylinder are, at once, strongly made to describe the arcs _a
M b_, _a c_; the mandrel revolving round the centre _E_, which is that
of the swivel and the bars round the stud _R_. But, in thus revolving, a
given point of the mandrel describes the _quadrant_ _a M B_, and a
contiguous point of the bars _L M_ describes the quadrant _a c_;
insomuch, that the mandrel _must_ have been forced out of the cylinder
in direction _G F_ by the distance _c b_; where we observe that, at the
beginning of this motion, the two curves _a b_ and _a c_ coincide in
their movements, and only begin greatly to diverge from each other in
the latter parts of these motions (see _M b c_.) The power, then, of
this machine, when the cylinder sticks fastest to the mandrel, _is
infinite_: and this power becomes weaker, and the velocity greater
toward the end of the operation; that is, when the cylinder has
slackened on the mandrel, and no longer requires to be driven with the
same force as at the beginning. It may finally be observed, that the
bars _L M_ are suspended by an oblique bar or chain _S N_ to the ceiling
of the room just over the stud _R_ or _I_, which is their real centre of
motion, in the above-described process.
OF
A SYSTEM OF MACHINERY,
_For cutting and trying Tallow by Power_.
The wheel _A B_, Plate 30, fig. 3, _was_ a horse-wheel, but may be a
_first motion_ of any given kind. It is placed on the ground-floor; and
over it’s centre is another shaft, having on it’s upper end a chopping
block _C_, which revolves with the wheel _A B_, as turned from below. In
this wheel, _A B_ geers a pinion _D_, driving the lateral shaft _D E_,
which has two functions: the first to work the lying shaft _F_, and by
means of the cams _G H_, to lift the contiguous stampers; and, by means
of the knives _I K_, to cut the tallow on the revolving block
before-mentioned. Over this block is fixed an oblique scraper, which
takes the tallow as soon as it is cut, and pushes it down an inclined
channel, placed at _C x_, into the boiler. The second use of the shaft
_E_ is to turn the _mill_ _M_, (better shewn at fig. 4), which is let
down into the boiler, in one stage of the process, and drawn out by the
tackle _N_, when not wanted. The use of this mill is to tear the fleshy
parts of the substance, while in the act of boiling, and thus to
disengage the tallow with so much the less heat, in order that it may be
so much the less coloured. Besides this machine, there is a grapple _L_
to be first used, which stirs the tallow in the boiler by the rotatory
motion of the arm _x_. This position of the grapple would alone
indicate what I have yet to observe--namely, that the boiler is a kind
of ring, the section of which is the line 1, 2, 3, 4, and it’s depth 1,
2, or 3, 4. To prevent, still further, the fat from being burnt or
coloured, the flue for the fire is conducted solely under the bottom of
the boiler, as shewn by the dotted lines in fig. 5: the smoke or heated
air being forced to make two revolutions under it, as indicated by the
arrows in this figure, where we see more particularly the fire-place _F_
in close connection with the rising shaft of the chimney at _G_; and
this is so, because, with so great a length of horizontal flue, the fire
would not enter the chimney till it had been heated to a first degree.
There is, therefore, an opening into the chimney at _a_, and the fire,
in lighting, is suffered to escape directly from the fire-place into the
chimney; by which means, continued a few minutes, there is draught
enough created to make the fire take its useful course through the flue
afore-mentioned. I may just observe, reverting to fig. 3, that _O_ shews
the fire-place _in elevation_, and _p_ the entrance into the flue, which
last is double under the boiler, as shewn in fig. 5. Finally, the 4th
fig. shews an end view of the _tearing-mill_, before-mentioned; but here
on a larger scale, _A B_ being a part of the side of the boiler.
OF
A WASHING MACHINE, FOR HOSPITALS,
_Which confines the offensive Matter till cleansed away_.
Doubtless, the salubrity of every place, where _many_ people are
collected, would be much increased, if all impure exhalations were
expelled as soon as formed; and this is especially true of those awful
but sublime receptacles, provided by Philanthropy, for the sick, the
wounded, and the dying! To assist in the work of purifying the
atmosphere of these doleful abodes, was the object (30 years ago) of the
VENTILATOR, presented in page 170 of this work. But, I conceive, that a
share of evil, quite as great, resides in the putrescent qualities
contained in or connected with the clothes, the bed-linen, the
dressings, &c., of the inmates of an hospital; to whose sacred claims on
the efforts of every good citizen, the present article is devoted.
This Washing Machine (see Plate 31, figs. 1 and 2) is a triangular (or
square) box _A B_, furnished with a lid _a b_, so fitted, as, when
screwed down, to be hermetically closed.--And, N. B., to facilitate
_this_ operation, I use in it a particular kind of screw (invented for
the _hose_ of fire-engines), which I shall now describe. I take a common
screw, with it’s nut, and cut away the threads of both, at two opposite
_quarters_ of their respective circumferences, so that the screw can
_enter the nut to the bottom without turning_; and the stuffing between
the shoulders is so well fitted, in thickness, as to secure the
penetration of the threads of the nut and screw the moment the latter
_begins_ to turn. There is thus a full quarter of a turn, in which the
nut and screw will press as strongly as though the threads had not been
cut away; and thus are _nine tenths_ of the time required to use a
common screw _saved by this simple process_: and thus, then, I close the
lid afore-mentioned.
This Machine is further composed of a wheel _C D_, and a pinion _E_, to
turn it with, either by hand, or by any proper application of power. The
wheel turns the box _A B_, and thus agitates the contents in a way not
dissimilar to the operation of the dash-wheels of calico printers. But,
again, this wheel and vessel turn upon _two hollow gudgeons_ _c d_; one
of which is destined to convey cold water into the wheel from the
reservoir _F G_, to regulate which is the use of the cock _f_: the
stuffing box _e_ being made as _good_ as possible, in order to prevent
all leakage, either of air or water. The second hollow axis _d_ serves
two purposes: it gives a passage to the fetid matter of which the
expulsion is desired, and conveys it through the cock _g_ to the _sink_
or _sough_ below _h_, _without any communication with the surrounding
atmosphere_.
But we said this hollow gudgeon had a second use: it is to bring steam
into the revolving vessel _A B_, from any proper boiler beyond _K_,
when that part of the process requires it.--There are, moreover, two
partitions _C D_, _l m_, made near the ends of the vessel, and pierced
with many holes, in order to suffer the cold water to flow in, and the
dirty water to escape, without choking up the respective passages: and,
finally, at the eduction end of the Machine (see _n_, _o_, _p_, fig. 2),
there are placed three pipes, reaching from the angles of the box to the
hollow centre, and furnished, at those angles, with valves, opening
outwards; which thus form a kind of hydraulic machine to raise this
matter from those places to the hollow centre, and thus, after a certain
number of revolutions, to expel it entirely.
The process, then, for cleansing the objects contained in the vessel _A
B_ (including the condition of cutting off all communication with the
ambient space,) is as follows:--
1st.--These objects are dropped into the vessel as soon as produced, and
the vessel is filled, one half or more, with cold water from the
reservoir _F G_. The things are then left to _steep_ in this bath for a
day or two, or what space of time the periodical mutations of the house
permit. By which operation _alone_, the miasmata are already much
confined by the water, even though the lid of the vessel should be but
partially shut: after which, this steeping operation may be continued,
with the accompaniment of a few turns of the handle (_E_) to fully
saturate every part of the mass. In the second place, a small stream of
water is let through the cock _f_, and the wheel _C D_ is kept turning
for a few hours, to discharge the cold water and the most offensive
matter, through the cock _g_, into the sink: and, thirdly, the
steam-cock _K_ is opened (that _g_ being shut), by which means steam is
brought into the vessel _A B_, and the whole soon raised to the boiling
temperature. This state of things is continued, as long as it is found
necessary; the motion, of course, being also continued, and even
accelerated, that the mass of objects may _fall_ from angle to angle,
and be thus _well washed_--that is, well _finished_, if _plain_ things;
and fully prepared for finishing, by hand, if of a nature to require
close attention. And, finally, in many cases, the warm process may now
be abandoned, and a new stream of cold water be injected, accompanied by
a due motion in the vessel, so as to _rince_ the contents; and thus
leave nothing to do for the laundresses, but to dry and mangle, or
_iron_ them; where, it is plain, that no inconvenience can have arisen
from this process, either to these persons, or to the other inmates of
the house.--Hence, then, this Machine _has the properties announced--of
confining the offensive matter until cleansed away_.
OF
A MACHINE,
_For propelling Boats, on narrow Canals, without disturbing the
Water_.
The application of steam-power, to the motion of boats on narrow canals,
is, I believe, much impeded by the consideration that the agitation of
the water injures their banks, and would finally destroy them. On the
other hand, it is known, that to drive a vessel, by acting on a fleeting
medium, such as water, we must, at once, submit to lose about one half
of the whole power employed--that is, the power, armed with energy
enough to produce the required velocity, must go through twice the space
that constitutes the _way_ or progress of the vessel. This depends,
however, on the size of the floats or paddles employed, compared with
the section of the boat, as modified by the form of the prow; but it is
difficult to employ a paddle so large as to suffer more resistance from
the water than the boat itself; and, if they are found _just_ equal, the
_loss_ of power is exactly one half of the whole. These, then, are the
two difficulties which I hoped to avoid, by the method now to be
exhibited.
The idea is this--To have a large and heavy wheel _A_ connected with a
_long_ shaft _B_, reaching from the boat to the shore, and, turning that
wheel _in_ the boat, to propel the latter, by means of it’s rolling
motion, on the bank or track-way; or, in some cases, on a proper rack,
placed there for that purpose.
The Machine itself is represented in figs. 3 and 4, of Plate 31; fig. 3
being a stern-view, and fig. 4 a side-view, both of the machine and the
vessel. _C_ is an axis, placed along the vessel, and turned by _any_
convenient power--as a horse, a steam-engine, &c. On this axis,
considered as the _first motion_, are fixed the two bevil wheels _b c_,
from which the long shaft _B A_ of the rolling wheel takes it’s motion.
The use of the two wheels _b c_, is to drive the boat in the same
direction on whichever side of the boat the wheel _A_ may be placed; for
this, of course, must follow the track-way, which is sometimes to the
right and sometimes to the left of the vessel.--Between the two wheels
_c b_, is a sliding block (or catch-box) _d_, in which the shaft _A B_
of the large wheel has it’s lower pivot, and by which it’s wheel _B_ is
almost instantaneously shifted from one to the other of the vertical
wheels _b c_: the catch-box _d_ being itself _worked_ by a lever, of
which the end only is seen at _e_, fig. 4. In fig. 3, there is further
shewn a rope or _stay_ _f_, which, fastened to the socket _s_, of the
rolling wheel _A_, and fixed in the middle of the boat, at the greatest
possible distance from it, serves to keep that shaft at or near an angle
of 90 degrees with the boat’s side: so that (the vessel being _long_) it
becomes easy by means of the rudder, assisted, perhaps, by _lee-boards_
to keep the _way_ of the boat in a line parallel to the shore,
notwithstanding the tendency to veer outward, given by the wheel _A_,
while acting on a point so far from the body of the vessel.
I further observe, that, in order to shift the apparatus, with a certain
facility, from one side of the boat to the other, there is a mast _M_
placed ahead of the mechanism just described, which rises as high as the
length of the main-shaft (but can be _lowered_ to pass a bridge, &c.),
and to the top of which is fixed the block _g_, through which a rope
passes from the foot of the mast to the above-mentioned socket of the
wheel _A_. By this rope the wheel is hauled up till nearly ready to fall
over the centre; when a push from below will complete that passage; and
the wheel _A_, being afterwards _lowered_ by the rope _h i_, will soon
find it’s proper position on the other side of the boat, as before
anticipated. Where, it should also be remembered, that this shaft must
have a joint and socket, to permit it’s being bent, to pass a bridge,
&c.
Hitherto we have supposed this rolling wheel to act on the bank or
track-way solely by it’s weight; but this is not our only resource; for
this wheel might be made of a moderate weight, and be pressed down by a
brace reaching along the boat, toward the head and stern (see _k l_,
fig. 3.), and _hauled taught_ through an eye of the socket _s_; by which
_manœuvre_ (the points _k l_ being lower than the centre _A_ of the
wheel) the latter will be pressed forcibly downward, and cause that
cohesion there, from which the boat is ultimately to take her motion.
And, as to the wheel _A_ itself, I have _not_ represented it in the very
form I should wish it to have, because it can be sufficiently described
in words. I should cast this wheel (if made at all in metal) as a
_shell_, the outside of which would be what is really seen in the figure
(at _A_), and the rim would have in it mortices, like those which are
made for iron wheels destined to receive wooden cogs, and geer with cogs
of iron. In fact, this would become a wooden-toothed-wheel, with its
teeth roughly formed and placed, so as to occasion a small expence, and
to be easily changed, when worn away by the friction on the track-way.
Thus would, I am persuaded, a very moderate weight in the wheel, and as
moderate a pressure from the braces _k l_, connect the wheel with the
road enough to produce the desired effect, with a trifling _loss_ of the
power employed. And thus might we navigate a narrow canal, with a great
saving of expence; not to mention that other advantage of avoiding
entirely that injury to the banks, which must attend every system of
propelling the boats, founded on the agitation of it’s waters.
OF
A MACHINE,
_For working, swiftly, the Slide-valves of Steam-engines_.
The Slide-valve is an excellent substitute for the _hand-geering_ of
steam-engines, from the simplicity of form which it introduces, and the
certainty of it’s recurring effects. But it is, I believe deservedly,
reproached with being too sluggish in it’s operation, at the very moment
when _activity_ would be most desirable--namely, at the beginning of the
strokes; insomuch, say some, that the _power_ of the engine is
materially lessened by it. The fact is, that the _excentric_ (usually
placed on the crank-shaft) is almost always moving, and with it the
slide-valves also; which thus open by _slow_ degrees, when they should
open by _rapid_ ones.
Without discussing the question further, I cannot refrain from
introducing this application of the principle of my Parallel Motion,
given in page 237; which appears to me greatly calculated to obviate
these difficulties; and thus to leave the slide-valve in possession of
all it’s own advantages, with the addition of those which have hitherto
belonged exclusively to the Hand-geering System.
I have represented this Mechanism in figs. 5 and 6, Plate 31: where _A
B_ shew the crank-shaft of a steam-engine, working by means of
slide-valves, the place of the _excentric_ being at _a b_, in a line
with the pulling-bar _e f_. Instead, then, of the usual connecting
_frame_ between the excentric at _a b_, and the valve-lever at _g_, I
use for the above purpose, a lever _e f_ terminated by an arc _o_,
furnished (in the present instance) with _five_ teeth, and connected by
the joint _e_ with the valve-lever _g_, in the usual manner. In the arc,
which terminates this lever _to the right_, are the five teeth
above-mentioned; and, they geer in the _ten_ teeth of the wheel _c d_,
which will be seen (in fig. 6) to be on the same shaft with the
spur-wheel _m_, itself driven by the spur-wheel _n_, of twice the
diameter. This wheel _c d_, therefore, makes two revolutions for one of
the crank-shaft: and, supposing it to turn in the direction of the
arrow, it will first of all draw _upward_ the arc _o_, producing no
effect on the valve-lever at _g_; but, when the tooth _r_ is arrived at
_p_ (the tooth _p_ being then arrived at the entrance of the curve _q_),
the wheel _c d_ will begin to draw the arc _o_ along with it, round it’s
own centre; and, the teeth of the arc being kept in it’s teeth by the
similar curve _q_, the valve-bar will be drawn from _g_ to _h_, in the
course of _one quarter_ of a revolution of the crank-shaft _A B_. But,
now, the tooth _r_ of the arc _o_ will be found at _s_: and, therefore,
the further revolution of the wheel _c d_ will carry the arc _o_
downward toward _t_, until the tooth _r_ has reached the point _t_; that
is, until the wheel _c d_ has made another half-revolution, and the
shaft _A B_ another quarter; when, as before, the arc _o_, conducted by
the curve _t r_, will again drive back the lever _e f_, till it comes
into it’s present position: after which, their motions will be regularly
continued. It is, then, evident, that the slide-valves are thus opened
and shut, each during one _quarter_ of a turn of the crank-shaft _A B_;
and thus they remain stationary during another quarter, and that, in two
positions of said shaft diametrically opposite to each other. And thus
have we a simple mean, adaptable to every engine, of giving it much of
the advantage of the hand-geering system, while preserving _all_ that of
the slide-valve principle. And, were it desired to lengthen the
_interregnum_ of the opening motion, it would be done by making the
wheel _c d_ smaller, and the ratio of _n_ to _m_ (see fig. 6) larger in
the same proportion.
I observe here, however, that care should be taken not to make the valve
motions _too_ rapid, nor the intervals between them too long; for, I
consider one of the best properties of this motion to be, that it acts
_like an excentric_; that is, slowly at first, most rapidly afterwards,
and finishes as slowly as it began; which is a _precious_ quality in all
reciprocating machines.
Finally, I would remark, that the two last _rounds_ in the rack of the
arc _o_ might be rather larger than the intermediate ones, and turn,
moreover, on pins, so as to suffer less friction when rolling on the
conducting curves _q_ and _t_. There might also be a plate or cap
rivetted or screwed over all the teeth, so as to strengthen each one, by
the force of the whole, as is shewn in fig. 1, Plate 29; from which, as
before observed, this Mechanism is deduced.
* * * * *
The foregoing completes the Third Section of my work: and gives an
article beyond the twenty, first intended:--which I thought important
enough to claim this distinction. I now beg leave to add a remark or two
on the text and plates of this, and the Second Part, by way of clearing
up some obscurities, that might otherwise embarrass my readers.
And, first, in fig. 1, of Plate 21, the receiving vessel _M_,
erroneously _appears_ to form part of the wheel _D E_; but is, in
reality, placed _before_ it, as in all similar cases.--And, further, a
small deviation of the circular lines, in Plate 22, has set the plate
and it’s description, in page 192, _at variance_; the difference between
the lines _o p_ and _C q_ being _not_ “imperceptible,” as there stated.
I wish, then, that the dotted radius _A o p_, in the said fig. 2, may be
carried (or supposed) halfway between _p_ and _C_. Finally, in page 200,
line 8, the 24th Plate is incorrectly called the 25th.