Part 18

But we have another important property to speak of. The colours on the two cylinders must be _fitted in_, laterally, as well as longitudinally: and the Machine performs this by an easy method. At each side of the Machine (see figs. 1 and 2) is fixed on a centre _i_, a short lever _k l_, the bent end of which (_l_) rises just to the brass step which carries the mandrel of the cylinder _a_, and is formed so as to push that step _inward_, when it’s end _k_ is pressed _outward_; which latter motion is occasioned by the screw _m n_, which goes all across the Machine, and performs the same office on either side as wanted. This then, is another economy of time and pains; this setting being usually done by passing round the Machine, from one side to the other.

Finally, _R S_ shews one of the cross-bars by which the two cheeks are connected. They are formed as portions of a hollow cylinder, and screwed to the cheeks through flanches, the breadth and form of which give considerable strength to the Machine; which is further strengthened by the bars _T V_ and _W X_, in it’s upper parts.

In the above description of this Machine, (in which the parts common to other machines are omitted) I have endeavoured to avoid all invidious comparison: and have only said what my additions appear to warrant, and what, I am persuaded they will justify, when this Machine shall be compared with others, placed in the same circumstances _for the sake of liberal comparison_.

OF A MACHINE _For clearing turbid Liquors_.

I confess, I again stand on a kind of forbidden ground; and am uncertain to what _degree_ this Invention will justify it’s title. Yet I think myself safe in expecting it will produce an useful effect. But the fact is, I never _fully_ proved it: the apparatus with which, more than twenty years ago, I was trying the System, having broken in the experiment--which I then had no opportunity of resuming.

I had then, as formerly, asked myself a question, viz: “will not the centrifugal force of a _heavier_ body, suspended (without chemical action) in a _lighter_ fluid, increase the subsiding tendency, and _quicken the clearing process_?”. I then thought “yes,” and do not yet see why it should not. But not having any absolute _fact_ to build my conclusions on, I must leave the whole matter to time and experience; and crave the candour of my readers in favour of my somewhat bold assumption.

This Machine then, which _is to_ purify muddy liquors by motion, is thus composed: a perpendicular axis _A_, (Plate 37, figs. 3 and 4) turns very swiftly, surmounted by a conical cap _B C_, so formed, as to receive and _lodge_ in it’s thickness, four or more vessels _a b_, _f e_, which hang on pins _c d_, near that centre and have the liberty of leaving it by the centrifugal force, round the said pins, until lost in the thickness of the cap above mentioned; where they turn on the common centre, without suffering any resistance from the surrounding atmosphere. This conical cap _B C_, &c. is made as light as possible, by protuberant ledges, but it’s solid _form_ would be restored by lighter substances fixed between the arms, so as to add _little_ to the friction or resistance of the whole mass. Any turbid liquor then, being introduced into any pair of these vessels while in the position _g h_, fig. 3, and put into swift motion, will have it’s muddy particles thrown from the centre, and (I presume) soon deposited at the greatest possible distance from that centre: since, although the centrifugal force will add, in the same degree, to the tendency outwards of the particles of the _liquid_, and make them _gravitate_ more towards the circumference; _that_ force will _not_ render the liquid less _fluid_--which, therefore, will suffer the _clearing_ process to take place _sooner with motion than without it_; and this is all I dare advance in the present state of my knowledge on this subject. Thus have I again reckoned on the kind forbearance of my readers, and risqued a little more of “the bubble reputation.”

My readers will supply one remark I had omitted--which is, that if bodies heavier than the fluid, recede faster from the centre _by_ this motion, than without it, _lighter_ bodies will approach toward the centre, and be there collected for the same reason--another cause for which, will doubtless be the pressure occasioned by this centrifugal force in the revolving fluid.

OF OPEN CANALS, _As Hydraulic Machines_.

I have said, and shall still say, much on the desirableness of making use of a greater portion of that gigantic agent--WIND, than has yet been customary. This article is another attempt to urge it’s propriety. But it will be of no use to those who cannot extend their views beyond the present state of things, to that possible state which every successive mechanical improvement appears to anticipate or promise. These speculations of mine, suppose extensive means and extensive necessities: and they promise results still more extensive. In a neighbouring kingdom, where the country is, as it were, redeemed yearly from the ocean’s grasp, what would not it’s inhabitants give for a security against the encroaching tide? or the means of saving several months to agriculture, by the speedy disembarrassment of it’s fields from the common destroyer of health and produce? It is even said, that in the last winter, some _dykes_ in Holland were broken, and many lives lost by inundation: and in our own country there is many a submerged spot, over which there blows wind enough to drink up, or throw out, it’s last particle. I submit then, the present means, as capable, with proper modifications, of forwarding every analogous purpose; and thus as worthy to occupy the attention of every friend to rational improvement.

If my 38th. Plate were considered as a _corner_ of any inundated country, whose boundary were a dyke contiguous to this chosen spot, I would propose building a long curvilinear canal _A B_, of which the middle space should receive and contain the lower water; and the two outside spaces the upper: especially the outer circle, which should communicate with a few branches _C D_, leading to and through the dyke before mentioned. In the two outside canals should float a pair of boats (long and light) _E F_, joined together by one or more cross-beams _G_, which would produce the double effect of connecting the boats so as to make them _bear much sail, without oversetting_; and of carrying along in the middle or lower canal a kind of _water-drag_ _H_, that should take with it the under water, and raise it’s level nearly to that of the upper canals--into one of which it would enter through it’s lateral valves, and thence flow into the eduction canals _C D_ as before stated. My idea will be better understood by referring to the small figs. 2 and 3, at the bottom of the Plate: for they are, _one_, the transverse section of the canals with the boats, and the other a longitudinal view of one of the vessels in it’s canal, with the water-drag _H_ in the act of making (what is technically called) a _boar_, of the lower water; and raising it above the level of the valves _I K_, which open into the canal.

To recapitulate, _E F_ in fig. 2, are the two vessels seen sternwise, with their sails _supposed_ very large: _G_ the beam that connects them; _H_ the water-drag; and _O_ one of several valves which open _from_ the lower water, and close when the drag is going over them. In fig. 3, _H_ is the same water-drag, whose distance from the bottom is regulated by the brace _b_: it’s beam or shaft, being fixed to the crossbeam _G_, of figs. 1, 2, and 3.

Thus then, at _one_ passage of this double vessel along the curved canal _A B_, all the water in it’s middle compartment will be raised into it’s outer one: and be thrown into _the sea_ through the canals _C D_, &c. It appears, near _E F_ in this fig. 1, that the vessels _E F_, have friction pullies or wheels placed horizontally on their decks, to act against the sides of the canal and prevent the lee-way: thus converting the whole effort of the wind to a useful purpose. And here I observe, that if the wind blows in, or nearly in the direction of the diagonal, then, the vessel would go almost from one end to the other of the main canal without tacking, and thus do an abundance of _work_ at each return: for it is a common thing for ships to sail nine or ten knots an hour! And here note, that the present curvilinear form is given to the canal in order to take all winds, (tacking more or less often) whether coming from the inside of the curve or from the outside. I cannot but add that in this Machine--in that I have already given--or in those I may yet give, there is much to be found that promises useful application in many an important position. An example now strikes me. The reservoir at the Manchester Water Works might furnish room for a floating Machine, capable, on windy days, to do all the work of the steam engine, and thus economize a good portion of the fuel it consumes.

OF A PORTABLE ENGINE, _For extinguishing Fires_.

This Machine (see Plate 38, fig. 4) is intended to be carried or conveyed in a small cart, to the place where an incipient _fire_ may be preluding to it’s fearful horrors! It is, as to form, a common lifting pump, inclosed in a vessel of air, whose spring perpetuates the _jet_ in the usual manner. When used, it is held on two men’s shoulders, by means of a bar going through the ring _A_. Further, a rope is fastened to each of the extreme rings _B C_: and a stick put through each of the second rings _b c_. Two rows of men are then marshalled along the ropes; one set to _hold-on_, and the other to pull in regular time, the piston _c_ along it’s pump, thereby sucking water through the pipe _D_, and forcing it through the valve _v_ into the air vessel: from which it is forcibly expelled through the directing pipe _E F_. Here it is clear, that this small Machine is capable of an effect almost indefinite: since the rows of men may be very numerous; there being always people enough at a fire. To work the Engine by pulling, is nothing more than to repeat many a nautical manœuvre: and if only one man in the company should have learn’t to _sing the sailors’ song_, they would soon produce--“a long pull, a strong pull, and a pull altogether.” To be serious, a hundred men may as well work at this Machine, as ten; and the effect will keep pace with the cause. In a word, there is scarcely any limit to the abundance of water, that might be thrown on a fire by such an Engine as this; of which I shall say nothing more, save that the bar of the piston rod at _c_, is intended to be used for drawing it inward, by the efforts of two men, at each interval in the effort of the working-men. A mere inspection of fig. 4 will fully shew what here remains unsaid.

OF A WIND MILL, _With double Power_.

This Mill produces a double power, merely because it uses two pair of _sweeps_ or sails, both of which (though turning opposite ways) concur in giving the same motion to the vertical shaft of the mill. _A B_ fig. 5, (Plate 38) is the shaft in question. It has on it two bevil wheels or pinions _o_, _b_; bearing the same proportion to their respective wheels: one of which (_o_) works in the wheel _C_, fixed to the _outer_ shaft _a c_, and the other (_b_) in the second wheel _D_, which takes it’s motion from the inner shaft _E D_. This latter, then, is turned by the front sweeps _F G_; which revolve, as usual, “_against the sun_,” while the other sweeps _H I_, are braced round the large shaft _a c_, and turn _with the sun_--being sloped and _clothed_ for that purpose. Now, lest any doubt should arise, whether these two sets of sails would not injure each other’s motion--I would remark, that one principal effect of the front sail _on the wind_ would only be to turn it aside, and _thus_ make it the _more fit_ to turn the other sails, which _require_ to go the other way; and which, therefore, will rather be favoured than otherwise, by the aforesaid effect on the direction of the airy current. It may be useful to observe, that the two sets of arms can be put, circularly, into any given position, by means of the wheels _C D_, and will _retain_ that position if the proportions of the wheels to the pinions _o b_, are the same for each pair--a result which it is easy to insure.

I shall dwell no longer on this subject, convinced as I am that nobody will question the propriety of enlarging the scope of these operations. It is a subject I especially recommend to our Batavian neighbours--the more, as, without presuming to dictate on a subject they may think I have not experience enough to judge of--I have only a hint to give to their _Moolen Maakers_, to insure their attention to a subject so intimately connected with the welfare of their never-forgotten _Vaderland_.

OF A WATCH ENGINE, _To extinguish incipient Fires_.

It is well known, that many ruinous _fires_ have originated so _slowly_, that they might have been put out in a minute, had a _little_ water been at hand--especially with the power of _throwing_ it to a short distance. This fact makes it more desirable than it would at first appear, to have small vessels full of water, furnished, in themselves, with the power of forming _a jet_, without a moment’s delay! and this is the purpose of the _Watch Engine_, represented in fig. 6 of Plate 39.

In that figure, _A B_ is a cylindrical vessel, with spherical ends, made strong enough to bear (without danger) a pressure of several atmospheres: and into which is introduced, by a _condenser_, (which might be the very system _C p r_) a quantity of water sufficient to occasion the aforesaid pressure. The valve _C_ being water-tight, retains entirely this water; and the Machine is placed on it’s three feet, in a corner of the apartment it is wished to secure. It is seen in the figure, that the valve-pipe _C p_, opens into the ejection pipe _p q_, while the valve stem _p_ passes through a collar of leather, and comes in contact with the lever _p R_ while in it’s present position. If, now, any part of the house or apartment should be found to be on fire, this Instrument can be carried there instantaneously, by the pipe _p q_, _as a handle_; and the jet be levelled at the point desired: when, by taking the lever _p R_ in his hand, _with_ the pipe _p q_, the bearer will open the valve _C_, and thus have an immediate supply of water, in a state of impulse sufficient to quell a fire that might else have become so violent as to mock every attempt to extinguish it! This, then, is the object of the present simple tribute to public safety.

OF A MACHINE _For Engraving the Cylinders of Calico Printers by_ POWER.

The principle of this Machine is as follows: When two equal toothed wheels _a b_ (see Plate 39, fig. 1,) geer together, a given tooth of either wheel _visits_ a given tooth of the other, once every revolution: and will continue to do so as long as the wheels continue to revolve. But, when the wheels are _unequal_, as _A B_ fig. 2, then _different_ teeth in one wheel, visit the same tooth in the other, until, after a certain number of turns, the revolutions of both wheels have a common divisor. My System of equable Geering (see Part 2d. of this Work,) justified me in applying this principle to Engraving; and is the chief foundation of the Machine now to be described: for this System, as we have seen, communicates the very same kind of motion that two touching cylindrical surfaces would impart to each other by mere contact. The punch, therefore, will not _scrape_ the cylinder, when brought into the desired places of contact by the aforesaid process. Let us suppose then, (fig. 2) that the wheels _A B_, are to each other in diameter and teeth, as the numbers 2 to 3; and that a given tooth in the wheel _A_, (which we have pointed out by a dot) now touches a certain spot on the wheel _B_, marked by a dot like the former. When, now, this spot on the wheel _B_ has made _one_ revolution, the wheel _A_ will have made 3/2, or 1-1/2 revolution: and the tooth first mentioned, will be found diametrically opposite to the place where it touched the spot first adverted to. And if, further, we give the wheel _B_ another turn, the wheel _A_ will again have made 1-1/2 turn; and the tooth first mentioned will again visit the spot with which it coincided at the beginning.

To recapitulate--The 1st. turn of _B_ gave 1.5 turns of _A_, and The 2d. turn of _B_ gave 1.5 turns of _A_: --- Sum. 2 turns of _B_ & 3.0 turns of _A_:--

which numbers are thus in the inverse ratio of the number of teeth in the wheels respectively.

Referring again to fig. 3, there we see a cylinder to be engraven, (_M_) and a _porte-outil_ (or tool-bearer) _N_, connected by the wheels _A B_; whose teeth are singly inclined, like those that were considered in Part 2d. It can hardly ever occur, that the circumference of a cylinder can require to be divided into two parts only: but most often into a greater number, as 9, 11, &c. and it so happens, (from these initial diameters 2 and 3) that we must take _uneven_ numbers for our basis, in order to reduce the System to any thing like regularity. And, this admitted, the theory of this division will be as follows:

Let the chosen (uneven) number of figures required round the cylinder be called _m_: then must the number of teeth in the small wheel _A_, be likewise _m_: when the number in the wheel _B_, will come out uniformly _m_ + (_m_ ± 1)/2; in which formula every case of practice is included. For suppose, any uneven number to be required, say 11: Then will the cylinder-wheel _A_, have 11 teeth; and that of the _porte-outil_ (_B_) 11 + 12/2 = 17, or 11 + 10/2 = 16: either of which numbers, working with the 11 teeth of the cylinder-wheel _A_, will divide the latter into 11 parts, as was before stated.

It must, however, be observed, that, as expressing a set of teeth actually working, these numbers are fictitious; because the teeth would be too coarse to work well. The numbers thus found, must, therefore, be multiplied by 2, 3, or more, so as to bring the teeth to a _reasonable_ size, say 1/8 of an inch thick, according to circumstances.

As another example, take the following: suppose it were required to engrave a cylinder of 4 inches diameter--or 12.56 in circumference, and to put twenty-five figures round it, giving very nearly half an inch for each figure. Then the cylinder wheel (_A_) must have 25 teeth; and the porte-outil wheel 25 + 26/2 = 38: or, doubling both numbers to give the teeth a proper strength, the cylinder-wheel would have 50 teeth, and the porte-outil wheel 76.

To proceed now, in stating the principles of this Machine, it is evident (in this System of geering) that the diameters of the wheels must be in exact proportion with the number of their teeth, _taken at the pitch lines_; and that these pitch lines must be of the same diameters, respectively, as the cylinder to be engraven, and the porte-outil taken at the surface of the punch: which is saying, in other words, that the length of the punch must be regulated _after_ the diameter of the porte-outil wheel has been determined from it’s number of teeth, compared with those of the cylinder-wheel. But we shall return to this topic after having described more fully the principal parts of the Machine.

In fig. 5, (which is a kind of transparent view of one end of the Machine), _A B C_ is one of the stands or legs on which it rests; _a b_ is a section of the frame or bench, which supports the _headstock_ _C D_, one of which is bolted down at each end of the frame, (see also _C D_ in fig. 3.) This figure shews the transverse form of the headstock, with the centre (_c_) of the porte-outil; and _e d_ are the _two_ wedges that go through the headstock to support the step of the cylinder, of which the mandrel appears at _f_. This mandrel-centre is also covered with a second step, over _f_, by which it is kept down by means of a regulating screw _A_, (fig. 3) which finally determines the degree of nearness of the cylinder to the porte-outil, and thus the depth of the engraving:--that is to say, this regulating screw influences this depth as far as the wedges (_e d_) permit: for by the screw _d_, these wedges slide on each other so as to raise or let fall the steps _f_, by small degrees; the position thus given being _confirmed_ by the said regulating screw. It is needless to say that this operation takes place at both ends of the Machine, (_C_ and _D_) and thus places the surface of the cylinder in a line exactly parallel to the slide _n q_ of the porte-outil.

In fig. 3, all the parts thus adverted to, are given in a front view--where we may observe, that the rope marked by dots at _R_, is a loaded friction-drag, used to prevent the porte-outil from _over-running_ the cylinder, when the punch is just emerging from between them.

The same figure 3, shews also the position of the frog _x_, in the triangular slide of the porte-outil; the latter, as well as the cylinder, borne by the headstocks _C D_. Moreover, the rack _w_, which gives the end-motion to the punch, is here shewn, as going through the frog, and connected with it in one direction by the catch _o_: and at _n_, there is a spring, formed like a horse-shoe, the use of which is to push the frog, by the catch _o_, _to the right_, whenever the rack is _suffered_ to go that way, by the mechanism hereafter to be described.

The _frog_, then, (so called because it seems to leap when the Machine works) must now be adverted to: it consists of an under mass, formed prismatically to fit exactly the slide _n q_, cut out of the porte-outil _N_. This mass is capped by a thickness of steel, which completes the passage for the rack _n w_, and offers, besides, a compartment for the punch-clams _o_, and another (_x_) for a wooden or steel _bridge_, being a portion of a cylinder, so formed, as to support the engraved cylinder after the stress of the impression is passed, and thus to equalize the depth of the engraving. The compartment for the punch-clams at _o_, is terminated to the right hand by an obtuse angle near _x_, which serves as a centre, when, by proper fixing screws in the rim near _o_, it is found necessary to place the punch a little awry. The other properties of this _frog_ will easily be supposed by my mechanical readers.