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PICKWORTH'S PADDLE-WHEEL. PICKWORTH'S PADDLE-WHEEL. the paddle parallel to its side edges ; not, The prefixed engravings represent a
however, in the centre of the side, but at new paddle which has been invented by
a short distance therefrom, projecting a Mr. Henry Pickworth, of Sipson, in the
little beyond each end. This axis is also county of Middlesex, and for which so put into the frame as to turn toward Letters Patent have been granted. The
the vessel's side as it closes upon the advantages claimed for the wheel are,
frame, by which means a sea striking the that it does away entirely with concus
wheel even on its broadside would, it is sion, and therewith the tremulous moa apprehended, produce little, if any effect. tion so much complained of in steam
D is a hollow shaft, moveable in a collar, vessels—that it produces no tail-water,
the bore of which hollow shaft is of such and causes, consequently, no drag on the
dimensions, that the main shaft A shall vessel, or on the power of the engine- just be able to work within it without that it may be placed so deep in the touching it. To the outer end of this water that the propelling -paddles on both
hollow shaft, and as near to the side of sides shall constantly be below the sur
the vessel as may be convenient, is fasface, even in the worst weather-that the
tened an eccentric E; and to the inner paddles may be generally so arranged end (which is within the vessel) there is that every paddle upon ceasing to be for
fixed a wheel B, similar to the steeringthe time a propeller, shall present itself
wheel in large vessels. C is a cog-wheel obliquely to the floating medium, even
for palls to act on, so that the said holthough the wheel should be wholly sub
low shaft D, and thereby the eccentric E, merged—that it is not liable to be da. may be fixed or moved at will. On the maged or obstructed in its action by the
eccentric E there revolves a wheel F sea striking against it, and needs, there called the frame-governor, of the same fore, no protecting-case or paddle-box
diameter as the body of the wheel, and (saving thereby a great deal of very in
pierced like it with circular holes, which convenient top weight), the only substi
take the necks of the cranks GG, shown tute requisite, and that but occasionally,
without support in fig. 1, the framebeing a screen of canvass, or some other governor F being in that figure omitted light material, to prevent the
to render the drawing more intelligible. from
spray the wheel being blown upon the deck- The smaller paddle-frames II are in fine, that it is equally effective, or firmly fixed to the body of the wheel, nearly so, under all circumstances. quite independent of the eccentric mo
Fig. 1 is a side view of a paddle wheel tion, and may be considered as an opof this construction; in which, for clear- tional addition to the wheel, which is ness sake, one half the body of the wheel, complete without them. They carry and also some of its appendages, are paddles like those in the revolvingomitted. Fig. 2 is an end view of the frames, excepting only in point of size. same wheel, with all the parts complete. These frames have holes in their radial The same letters of reference indicate the bars, and also in their paddles, so pierced same parts in both figures.
that when the paddles are in the position In fig. 1 the wheel is supposed to be of fig. 1, the holes in the bars and the at rest, with all the paddles placed edge- holes in the paddles are in a direct line, ways, or nearly so, to the stem and stern so that one rou may be passed through of the vessel. In fig. 2 the wheel is sup- bars and paddles collectively, and thus posed to be in motion, and the lower maintain them in their relative positions paddles advancing.
whenever this may be required. The The body of the wheel HH is sul). paddles are so put into the frames, both stantially similar to that of the coinmon revolving and fixed, that they shall turn paddle-wheel, only that it is much nar- upon their axes, taking a general bearing
The radial arms have circular or support from the frames when proholes pierced through them at their ex- pelling, at which time they are at right treme ends, in which holes revolve trans- angles with the side of the vessel - and verse bars (with cranks GG at one end) when not propelling, having other bearwhich carry the larger paddle-franes Il. ings or points of rest also within the These frames support parallelogramic frames, which retain them at right angles paddles KK, each of which turns on an with the frames, or nearly so. axis, which axis runs from end to end of The lines SS, fig. 2, represent the axes
Fig. 4. of the paddles in the frames when revolv- ing of the paddles on so small a scale as ing as well as when fixed; both have the that to which we are restricted by the appearance of being continuous, but they
size of our pages. are not so in reality, that appearance be- In fig. 1 the wheel, as has been obing produced by the axes being in two served, is at rest; but a wheel of this planes, each of which is viewed edgeways. construction never could, in point of fact,
The lines TT, fig. 2, seen through and be as represented, unless the paddles of between the revolving-frames II, are the the fixed frames were secured in the mantransverse bars of the fixed frames.
ner previously described—for the broader The open paddle-frames, fig. 2, have sides of the paddles in the fixed frames their paddles coincident with their axes yielding to ihe force of gravity, would SS, and are thus partly hidden by tliem close those on the right hand, which, and partly confounded with them; it not however, would be opened the moment being possible to display the foreshorten. that the wheel was set in motion for for
PICKWORTA'S PADDLE-WHEEL. ward movement, that is to say, in the anee; the wheel, therefore, would condirection of the arrow; the centrifugal tinue as effective a propeller as before, as force, the pressure against the air, and ihe will be clearly perceived by reference to pressure against the water, all combining fig. 2. to produce the above effect. To obtain When a vessel has head-way upon her, this effect, however, the centrifugal force and it is desired to “ stop her,” let the of a moderate velocity would be more motion of the main shaft be arrested, as than sufficient. The paddles have been in the case of the common paddle-wheel; placed in this imaginary arrangement the way of the vessel through the water here represented, in order that their rela- will suffice to cause a pressure in the tive positions with the frames might be direction of the arrow, the revolving
frames which are closed will open, and Suppose fig. 1 to be set in motion in the fixed frames which are open will close the direction of the arrow. By inspec- and form a drag upon the vessel like the tion it will be seen, that the revolving- common paddle-wheel, but much more frames below the main shaft have the effective in proportion as the opposing broader sides of their paddles in advance paddles are deeper in the fluid ; and this of the circular motion of the body of the action, it will be seen, is entirely indewheel, and the revolving-frames above pendent of the cecentric, or any thing the main shaft hare the broader sides of connected therewith. If the motion of their paddles in the rear of the said mo- the main shaft be reversed, then back action; while the fixed frames, both above tion will be produced also, after the and below the main shaft, have the manner of the common paddle-wheel. broader sides of their paddles in the rear From the peculiar construction of Mr. of the said motion. The paddles in the Pickworth's wheel, the whole support of frames, both revolving and fixed, are so the revolving-frames, as well as of the arranged, that in opening they shall not fixed ones, is thrown upon the body of be able to attain to a perfect right angle the wheel. What is called the frame. with the frames, in order that when active governor F has inerely to retain the repressure exists, their sides may be ex. volving-frames in their assigned position, posed thereto unequally. It will now be whatever that may be. The consequence evident, that the active water pressure on
is, that there is no friction upon the ecthe broader and advancing side of the
centric E beyond what the more weight paddles in the revolving-frame while de- of the wheel F would produce, so that scending having a preponderance over the one man stationed at the wheel B is enapressure on the narrower and rear side of bled by means of it to turn the hollow it, must turn the paddle and close the shaft D, and with it the eccentric E, round frame. When, again, the frame has the main shaft, and thus change the posipassed the lowest point of the wheel, and tion of the point of support of the wheel ascended so far as to have no power as a F, and thereby the position of the revolv. propeller, the active water pressure will
ing paddle-frames. be in the rear of the paddle, which thus If there should ever be occasion to pressed behind will instantly yield and substitute sails for steam-power, an iron open the frame, so as to let the water pass rod being run through the holes in the through, instead of arresting it and caus- radial bars of the fixed frames, and through ing it to act as a drag on the speed. The the paddles corresponding thereto, as befixed frames must, of course, from the fore described, the wheel would present arrangement of their paddles, remain the exact appearance of fig. 1 ; and the open.
paddles in the fixed frames being thus Suppose, further, that the motion of the made immoveable, as regards their frames, wheel were continued, and that by a would act as lee.boards. heavy sea, or from any other cause, the In crowded rivers, and under other entire wheel were submerged, the pad- circumstances where great care is necesdles below the main shaft would con- sary, it is intended that a man shall be tinue effective as before, while all the stationed at the steering-wheel B, who paddles, both revolving and fixed, that with his foot may command the palls are above the main shaft, having their acting on C, and, by turning the wheel B, broader sides in the rear of the said mo. augment or diminish the power of the tion, would neither give nor receive resist- paddles on his side of the vessel, without PICKWORTH'S PADDLE-WHEEL.
325 interfering with the action of the main purpose; but it will probably be found, shaft. When the paddles are in full ac- in most cases, necessary to reduce the tion, one-half turn of the steering wheel diameter of wheels so used, and to in. B renders them entirely passive; and ii crease the number of their revolutions this be effected on one wheel while that proportionately. on the other side remains in full force, Following out this idea, let us suppose the vessel is brought short round upon that the fixed frames with their paddles her heel, independent of the rudder, are removed, and that the highest paddle which may, however, be used at the same remaining is completely under watertime.
the wheel propelling in the direction of From the water-line in the drawing, it
Now, a half-turn of the will be seen that it is intended to place steering wheel B would, without reversthis wheel so deep in the water that no sing or in any way interfering with the alteration in the loading or the trim of a motion of the main shaft, instantly give vessel can sensibly affect its propelling back action equal to the fore action on the power; in fact, unless a vessel be ihrown other side of the vessel; so that this nearly on her beam-ends, such a wheel movement of the steering-wheel B being as this can never be entirely out of water. performed on one of the two wheels only, Should the revolving-paddles ever be- the effect would be to bring the vessel conse from any cause unmanageable, the round upon a point within her keel, and fixed paddle-frames may be closed, and to make her turn gradually round upon the paddles secured in that position by that point as long as the wheels in that passing the rod, before spoken of, through position could be impelled. A man-ofihe fixed frame radial bars merely; the war would thus have the advantage of wheel may be thus converted in a few being able to bring her broadsides to bear minutes into the common paddle-wheel. in succession upon any given point by a
The fixed frames are so secured to the regular movement, without any effort bebody of the wheel, that they may with yond the first adjustment of the wheels their paddles be entirely removed in a ihe whole not the work of one minute. few minutes without interfering with any
The wheels in the case last supposed other part of the machine; they may be are assumed to be not only submerged, replaced also in an equally short space of but in a vertical position like that of the time. And when the fixed frames are so common paddle-wheel. Mr. Pickworth, removed, the wheel will remain as effec- however, considers that his wheel would tive as before.
be quite as effectual a propeller, if atNearly the same effects may be pro- tached to a vessel in a horizontal posiduced in a different manner. Suppose tion, as in any other. All that is thought the forward movement of the vessel to be to be necessary is a modification in the effected as previously described, and that arrangements of the vessel. the command is given to stop
her.” breadih of beam, with a light draught of The stopping of the main shaft would water, are the obvious requisites for a merely arrest the propulsive power of the
vessel with horizontal wheels; and these, wheel, which in many cases is all that is it is presumed, might be combined withi desired ; but should it he wished to add advantage for passenger-vessels and for a drag upon the vessel's
A vessel of the forın regulated to any extent from a mere somewhat like that displayed in the enline to the entire superficies of the whole gravings, figs. 3 and 4, might perhaps be of the immersed paddles—by a half-turn found suitable. of the steering-wheel B, or so much less Fig. 3 is a side view, and fig. 4 bottom than a half-turn, as may be deemed suffi. view. A, the gun or passenger deck; cient. A reverse motion of the main B, main-floor of the boat; C, the keelshaft then gives the back action.
floor; D, engine-room; E, wheels; In order to protect the wheel from gun- F, rudder; G, the position which the shots, it is intended that wheels on the wheel E would occupy if placed vertiprinciple of this patent shall be wholly cally in the usual manner; HH, coalsubmerged when applied to vessels of holes; and I, line of Avatation. Any
The arrangement shown in figs. 1 modification of this arrangement which and 2, without the fixed frames and their may suggest itself to the scientific builder paddles, would he suitable for such a might be very readily introduced. For
BRIGHTON RAILWAY BILL: example, the wheel itself may be made necessarily happen that at very few seasons of buoyant by a drum on the main shaft, if the year there can be the same temperature such an adjustment should be thought
in the external atmosphere and the stationary desirable,
air in the body of the tunnel; there must We are inclined, on an impartial con
necessarily be some marked difference, for in
the winter season the air in the tunnel will be sideration of the whole subject, to think that Mr. Pickworth has rather attempted
considerably warmer, and in the summer
season the air in the tunnel will necessarily too much by striving to combine all the
be colder than the external air. Such a vaadvantages of the best form of moveable
riation of temperature will expose persons in float-boards with all the advantages of health to the common affection notoriously the common paddle-wheel; while, at the termed catching cold, the source of other dissame time, to avoid the disadvantages of orders; they may be inflammatory or they may both one and the other, he has given a be of other kinds; but the common phrase of degree of weight to his wheel which may catching cold, I believe, arises from its beweigh considerahly against it. It is,
ing found by experience that people are apt however, but justice to remark, that by a
to take a disorder called a cold or catarrh by
sudden transitions from heat to cold er frem jndicious arrangement of his materials he
cold to heat. I entertain no doubt that the gets the needful strength with perhaps as
variations in temperature to which I have tle weight as possible. He will, we
referred will be sufficient to put persons even hope, excuse us for suggesting, that his
in health in danger of cold by passing through paddle-frame vertical bars might instead a tunnel. I think it must of necessity be. of plates of metal have rods (following so; for although a person may pass somethe outline of the plates) substituted for times with impunity, he cannot be always them with advantage. In the case of a assured of passing through a tunnel under sea striking the wheel on its broadside, the stated circumstances with impunity. Most the rods would offer less resistance than
striking effects would be produced on persons the plates.
of weak constitutions or who are invalids. If We beg these remarks to be under
your lordships and the Committee will perstood as applying to figs. 1 and 2 only,
mit me, I will generally state, without being
too prolix, the reasons for my entertaining før upon the horizontal wheel we do not
this opinion. The surface of the body and venture to give an opinion; all that we
the inner surface of the lungs are the two can say is, the arrangement seems to
portions of the living frame most exposed to us to be ingenious and worthy of con- the vicissitudes of temperature in the air. sideration.
Persons with weak lungs being subjected to We are informed that it is the inten- the alternation of heat and cold or cold and tion of Mr. Pickworth to charge no pa- heat, by such transitions must necessarily tentee's premium upon his wheels, but to
have disordered conditions of the lungs aggive permission to all respectable en
gravated ; so in the influences upon the exgineers to manufacture them, on con
ternal surface of the body, catching cold is dition of his being paid a small annual
commonly and justly imputed to the external
application of change of temperature; hence charge upon every vessel to which they
persons are said to “ catch their death of may be applied, so long as she may con
cold in dan sheets,” and on exposure to a tinue to use them. This, at all events, is
current of air, because the current of air, a proof that no advantage is desired by
though of the same temperature, does not the ingenious inventor other than what accord with the temperature or halo immethe real and positive superiority of his diately surrounding the living body, which wheel may procure for him.
in a healthy man is at 100 degrees, such halo surrounding his body approaching nearer
to the teni perature of his body than to the BRIGHTON RAILWAY BILL.
external atmosphere ; and hence, if a stream The Evidence against Tunnels. of air blows upon him, it produces a sensaSir Anthony Carlisle, M.D., examined by
tion of cold, and in fact it has the effect of Mr. Hill.
a different temperature from that which en
velopes or surrounds the person. Besides I am vice-president of the College of Sur- catching cold in passing through a tunnel, a geons, and have been a public practitioner person is subjected to all the modifications about forty-four years in London.
As a part
of disorder of the lungs which have a tenof my professional duty, but more especially dency to inflammatory nature, active or in my scientific pursuits, I have attended to chronic; and also erysipelas, a very dangerthe subject of tunnels on railways. It must ous disease, is known very frequently to hap