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THE LIBRARY 
 
 OF 
 
 THE UNIVERSITY 
 OF CALIFORNIA 
 
 PRESENTED BY 
 
 PROF. CHARLES A. KOFOID AND 
 MRS. PRUDENCE W. KOFOID 
 
 
A NEW 
 
 CENTURY OF INVENTIONS, 
 
 BEING 
 
 OF 
 
 ONE HUNDRED MACHINES, 
 
 RELATING TO 
 
 ARTS, MANUFACTURES, & DOMESTIC LIFE. 
 
 By JAMES WHITE, CIVIL ENGINEER. 
 
 Connoissons le principe 
 Nourrissons nous des Elemens. 
 
 Girard Syn. fr. 
 
 iflancljester: 
 
 PRINTED FOR THE AUTHOR, BY LEECH AND CHEETHAM., WBIGHT'S-COURT, MARKET-STREET. 
 
 AND SOLD BY 
 W. AND W. CLARKE, MARKET-PLACE ; E. THOMSON, MARKET-STREET ; % 
 
 T. SOWLER, ST. ANN'S-SQUARE, MANCHESTER. . 
 G. WILSON, 49, ESSEX-STREET, STRAND } LONGMAN, HCRST, REES, ORME, 
 
 AND BROWN, PATERNOSTER-ROW, LONDON. 
 AND BY THE PRINCIPAL BOOKSELLERS IN THE UNITED KINGDOM. 
 
 1822. 
 
 If} , 
 
entered at >tatfoners' 
 
PREFACE. 
 
 J_T has been my lot, during a long and eventful 
 passage through life, to have my attention forcibly 
 drawn to a multitude of Mechanical Subjects ; the 
 present review of which permits me to hope, that 
 in making them publicly known, I should render 
 an important service to the Arts and to Society. 
 But the manner of doing this has been so long a 
 question with me, that I have sometimes feared my 
 ability would be extinct before I could do it at all. 
 The reasons, however, that urge me to make the 
 attempt acquire strength with the lapse of time : 
 and whenever my declining health bespeaks the ap- 
 proach of that " night in which no man can work," 
 I feel deep regret, that this tribute should not have 
 been thrown into the treasury of human knowledge 
 while yet, by the favour of a good Providence, the 
 means of doing it were more fully at my disposal. 
 
 I have determined therefore to publish these 
 Inventions. Not because they have been ma- 
 tured into a regular System of Mechanical truth; 
 
 A 2 
 
 M367933 
 
iv PKEFACE. 
 
 but because they consist of many distinct objects 
 of immediate application : coupled with some 
 ideas of a more comprehensive nature, that may 
 probably extend the usefulness of this admirable 
 study, in the hands of Artists yet unborn. 
 
 The form, or rather the title of this work, has 
 but one example, that of the illustrious Marquis 
 of Worcester ; whose name may, perhaps, pro- 
 long the remembrance of mine: an event the 
 rightful anticipation of which, I confess, would 
 give me pleasure. Not that I either covet or re- 
 gard what is commonly called popular applause : 
 but the approbation of the wise and good I do 
 regard, and aspire to obtain : since that alone 
 seems to fulfil the adage " Vox populi vox dei." 
 
 On the subject of our respective Inventions, my 
 views are somewhat different from those of the 
 Noble Marquis ; whose description of his labours, 
 as the custom then was, seems chiefly calculated to 
 excite the desire of knowing them better : where- 
 as my wish is to infuse, at once, the knowledge 
 of my subjects into every head capable of re- 
 ceiving it 
 
PREFACE. V 
 
 This Work then, treats less of Theory than 
 Practice. What are called Principles in Me- 
 chanics, are, and must be, founded on numerous 
 suppositions; to present which to "the mind's eye" 
 requires often a forest of signs, which some read- 
 ers will not, and others can not penetrate ; so 
 that, for many, Theory might as well not exist. 
 This evil is increased when, as it sometimes hap- 
 pens, these suppositions are laid so far from reality, 
 as to leave the result, though correctly deduced, fur- 
 ther from the truth than the point to which a sound 
 understanding unassisted by science, would have 
 carried it To this extreme discrepance of views 
 between theoretical and practical men, may be 
 ascribed their well-known antipathy to each other 
 in indulging which, they are alike to blame! 
 since no theory inconsistent with fact can be com- 
 plete ; nor any fact be adduced, that a perfect 
 theory will not account for and confirm. 
 
 Happily these discussions do not affect my 
 present purpose. For although I shall offer no- 
 thing contrary to sound theory, I do not consider 
 that as my subject ; but make it my business to 
 
VI PREFACE. 
 
 present rational methods of producing useful ef- 
 fects. In other words to describe these Inven- 
 tions as connected with immediate Practice. And 
 if, hereafter, it should become desirable to resume 
 the discussion of any principle relating to these 
 subjects, I shall cheerfully enter upon it; but 
 hasten, mean while, to do what seems more impor- 
 tant to place the subjects themselves beyond the 
 danger of being wholly lost, whatever may befal 
 me in the course of those events which are still 
 among the secrets of Heaven. 
 
 In the pursuit of knowledge, in general, it is 
 often desirable to trace it from its upper source ; 
 and to know all the circumstances that have at- 
 tended its progress, down to the very moment 
 when it falls under our observation. Nor is it a 
 matter of indifference to examine the minutest 
 form which talent assumed, in the young mind 
 whose subsequent efforts have engaged our atten- 
 tion, or gratified us with more varied and solid 
 productions. In this view I have presumed to 
 think myself justified in commencing this Work, 
 by a succinct reference to those feeble efforts which 
 
PREFACE. Vli 
 
 marked my first steps in this career. Young I 
 then was, and my musings puerile indeed ! But 
 they were original : they were the links of a chain 
 which time has not yet snapt asunder and of 
 which my honoured Father saw the connection 
 with my subsequent labours, long before I thought, 
 myself, of any thing but working for the purposes 
 of amusement ; or, in the childish phraseology, of 
 "playing at work/' 
 
 Should any reader then enquire what were my 
 first avocations ? the answer would be, I was (in 
 imagination) a Millwright, whose Water-wheels 
 were composed of Matches. Or a Woodman, con- 
 verting my chairs into Faggots, and presenting them 
 exultingly to my Parents : (who doubtless caressed 
 the workman more cordially than they approved 
 the work.) Or I was a Stone-digger, presuming 
 to direct my friend the Quarry-man, where to bore 
 his Rocks for blasting. Or a Coach-maker, build- 
 ing Phaetons with vaneer stripped from the furni- 
 ture, and hanging them on springs of Whalebone, 
 borrowed from the hoops of my Grandmother. At 
 another time, I was a Ship Builder, constructing 
 
Till PBBFACB. 
 
 Boats, the sails of which were set to a side-wind by 
 the vane at the mast head ; so as to impel the ves- 
 sel in a given direction, across a given Puddle, 
 without a steersman. (See Plate 2. Fig. 3,) In 
 fine, I was a Joiner, making, with one tool, a plane 
 of most diminutive size, the [relative] perfection 
 of which obtained me from my Father's Carpen- 
 ter a profusion of tools, and dubbed me an artist, 
 wherever his influence extended. By means like 
 these I became a tolerable workman in all the me- 
 chanical branches, long before the age at which boys 
 are apprenticed to any: not knowing till afterwards, 
 that my good and provident Parent had engaged all 
 his tradesmen to let me work at their respective 
 trades, whenever the more regular engagements of 
 school permitted. 
 
 Before I open the list of iny intended descrip- 
 tions, I would crave permission to exhibit two more 
 of the productions of my earliest thought namely, 
 an Instrument for taking Rats, and a Mouse Trap: 
 subjects with which, fifty years ago, I was vastly 
 taken ; but for the appearance of which, here, I 
 would apologize in form, did I not hope the con- 
 
PREFACE. ix 
 
 siderations above adduced would justify this short 
 digression. If more apology were needful. ...Emerson 
 himself describes a Rat-trap : and moreover, defies 
 criticism, in a strain I should be sorry to imitate ! 
 my chief desire being to instruct at all events, and 
 to please if I can : without, however, daring to at- 
 tempt the elegant PROBLEM, stated and resolved in 
 the same words "Omne tulit punctum, qui miscuit 
 utile dulci." 
 
 The town of Cirencester (my native place) is in- 
 tersected by several branches of the river Churn, 
 whose waters are pure and transparent, and whose 
 banks, formerly, were much perforated by the 
 industry of the Rats that had made them their 
 residence. These holes had generally two open- 
 ings ; one at or near the surface of the ground, 
 and the other near the bottom of the river : so that 
 the rats could range the fields from the former, and 
 dive into the water from the latter where they 
 were often seen gliding along the bottom, either up 
 or down the stream. The Instrument for taking 
 them in these circumstances, was no other than my 
 Father's Walking-stick, (represented at A. Fig. 1. 
 
 B 
 
X PREFACE. 
 
 Plate 2.) connected with the curve B by the joint 
 C ; the curve having a string fastened to it, which, 
 passing through the body of the stick, rose to the 
 hand at D, for the purpose of closing the fork at the 
 proper moment. The Machine, thus constructed, 
 was put over the rat's back while in the act of div- 
 ing ; and by pulling the string C D, he was suffici- 
 ently pinched to be drawn out of the water, where 
 a Dog stood ready to dispatch him. 
 
 On the Mouse-trap (Fig. 2. and 4.) more thought 
 was bestowed. It appeared adviseable (I remember) 
 to lay the deceptive plan rather deep: and to lull the 
 little animal into a false security till the snare had 
 taken full effect ; and even then to hide from her 
 some of its horrors till she was far enough from this 
 vestibule of misery, not to deposit there any of those 
 tokens of distress that might deter other mice from 
 following her example. The trap then, consisted of 
 a long passage, formed spirally round the surface 
 of a Cone, like the figures we have of the Tower of 
 Babel. This passage is uncovered in Fig. 4 to shew 
 the entrance E, and the subsequent gates F G H, <frc. 
 which like the valves of a pump, gave easy entrance 
 to the victim, but forbade her return. At the length 
 
PREFACE. 
 
 of a mouse from the outer gate B, was placed the first 
 bait N, say a small rind of cheese, well toasted to 
 allure, but nailed down to prevent its removal. 
 Its position was further indicated by a train of meal 
 reaching from it to the outer gate B ; which latter 
 was nicely hung on pivots inclined a little to the 
 perpendicular, so as to open with ease but never 
 fail to close itself again. It had besides an horizontal 
 plate O, fixed to its bottom on the inside, so that 
 if the mouse attempted to open it that way, she 
 trode on this plate and destroyed the result of her 
 own efforts. 
 
 When, therefore, the little wretch had passed this 
 barrier, she was in reality taken : but unconscious 
 yet of danger, she nibbled the first bait with plea- 
 sure, and then skipped forward in search of more 
 substantial food : but to obtain this she must pass 
 more of these faithless gates, F G H, <fcc. which with 
 progressive effort she opened, and at length found 
 the inner compartments replete with good things, 
 on which she fed to satiety, and then only began to 
 think of her situation. Nor yet, with much alarm: 
 for at the end of this labyrinth, so easy of access, 
 she hoped to find an easy exit. But alas, these 
 
Xii PREFACE. 
 
 hopes were illusive. Instead of light, she found the 
 dark gallery O ; the least evil of which was to be 
 too narrow for two mice abreast, since it overhung 
 a tremendous cavern, Q, that entirely occupied the 
 Cone below, and was filled with water deep enough 
 to drown her, were she to fall, or be jostled into it. 
 And one of these disasters she could hardly escape ! 
 for other mice would not fail to be beguiled into 
 this cruel Bastille ; to reach the same spot ; and 
 finally, to plunge her into this watery grave. 
 
 Having endeavoured to recollect the substance of 
 these youthful attempts to unite cause and effect, 
 or to fulfil a given purpose by preconcerted means, 
 I now turn to things of greater importance, and more 
 worthy to be the theme of my readers' attention. 
 The subjects to be presented will observe a miscella- 
 neous order; since they have not only originated at 
 different periods, but offer likewise different degrees 
 of interest to equalize which throughout the Work, 
 appears a desirable attempt. As to the manner of 
 treating each subject, it will be, generally, to des- 
 cribe the Machines by a reference to the Figures ; 
 and then to add some remarks on their date, con- 
 struction, properties, and uses. 
 
PART FIRST. 
 
 A NEW CENTURY OF 
 
DYNAMOMETER; 
 
 OR, 
 
 Machine for measuring Power and resistance while in Motion. 
 
 JLlYNAMICS being a science that relates to bodies in motion 
 comprehending not their weight only, or their velocities only, but 
 the product of the one by the other ; so the Dynamometer is a 
 mean of measuring both these circumstances together, and thus 
 of making known the momentum of a power or resistance in 
 motion. As this Machine has a connection more or less inti- 
 mate with almost every other, it seems entitled to the first place 
 in this collection. Its description follows : 
 
 In Plate 3, Fig. 1 and 3, M M, represent two cheeks, standing 
 parallel to each other, and forming a cage or frame by means of 
 the cross bars E and the nuts F G. A P, Fig. 2, is the principal 
 axis of the Dynamometer, fixed to the wheel R N of which it is 
 the centre of motion. It has a square end A, formed to receive 
 the wheels and other supplemental parts, to be mentioned below. 
 After the square A, comes a bearing E, to fit the steps in the 
 frame; and beyond the wheel R N is a cylindrical part O, fitted 
 to the hollow axis T of the wheel or frame I K, (Fig. 4) ; and 
 in fine the form P of this shaft fits and turns in the cannon of 
 
16 
 
 the axis B H, of the wheel CD; so as, when put together and 
 connected with the frame I K, to assume the form C R F G of 
 the third figure. L P, Fig. 3 and 4, are two intermediate 
 wheels (thus placed to balance each other on the common centre 
 T) whose axes turn on proper steps in the frame I K ; and 
 which by their teeth connect the motion of this frame with that 
 of both the wheels R N/ and C D. 
 
 Such are the parts of the Dynamometer properly so called ; 
 and they are shewn as in their places in Plate 1, where the parts 
 above described, as far as visible, are marked with the same 
 letters. Moreover, this figure shews a scale -bason P, to re- 
 ceive the weights used to measure equable powers, as will be 
 seen hereafter. 
 
 Plate 4 contains some of the auxiliary parts of this Ma- 
 chine. But before we proceed to describe them, it may be 
 proper to observe that the measuring power, by the action of 
 which at K, (Fig 1) the energy of the force is transmitted to 
 the resistance, must, to meet every case, be susceptible of 
 change, according as the resistance or force to be measured is 
 aniform or convulsive. For example, in a mill grinding corn, 
 driven by a fall of water, the whole process is sensibly uniform, 
 and a weight at P is the proper measurer. But if it were desired 
 to measure the effect of a pump driven by water, or of a tilt 
 hammer worked by a Steam Engine, then the measuring power 
 at P must be a spring : for in these cases the vis inertice of 
 
17 
 
 a weight would add to its force of gravity when suddenly raised, 
 or detract from it when the resistance should suddenly give 
 way. Whenever therefore, the force and resistance are both 
 equable, a weight will best measure them ; and when either is 
 convulsive, a spring : but a spring so equalized as to offer the 
 same resistance at every degree of tension it may have to sustain. 
 
 In the 6th. and 7*h. Figures, (Plate 4) these demands are 
 fulfilled. The first represents a barrel -spring, similar to that 
 of a watch, but surrounded by a fusee, the increasing radii 
 of which compensate for the increased tension of the spring 
 in the barrel G ; so that the action of the system on the chain 
 is always the same. 
 
 The 7*h. Figure exhibits a spring adapted to heavier pur- 
 poses. It is a cylinder nicely bored and hermetically closed at 
 bottom ; in which works a Piston P plunged in oil, which 
 when forcibly drawn up forms a vacuum in the cylinder, into 
 which the atmosphere endeavouring to enter, acts like a spring 
 on the Piston ; and preserves the same stress whatever be the 
 height of this Piston in the cylinder. 
 
 This then, is also an equallized Spring, such as these ex- 
 periments require ; but it is not my invention. I first saw a 
 vacuum used, as a spring, by my noble Patron, the late Earl 
 Stanhope : to whose mechanical attainments, I owe this tribute 
 of applause on the present occasion. 
 
18 
 
 In the three Figures of this Plate, 8, 9, 10, are shewn two 
 of the means I use for creating those factitious resistances that 
 are sometimes wanted in the process of measuring power. In 
 Fig. 8, E H F, is a gripe or brake, such as millers use to 
 stop their wind-mills with ; fixed under L, it surrounds the 
 wheel E H, and is then fastened to the end F of the lever K L. 
 The hrake is thus pressed wdth greater or less force against the 
 wheel, as the weight I is placed more or less distant from the 
 fulcrum L of the lever. By these means a resistance of the 
 equable kind is produced, capable of being adapted to any 
 power it may be wished to measure ; which makes this Dyna- 
 mometer a real trihometer or measurer of friction. 
 
 The second kind of resistance brought forward in this Plate, 
 is a Pendulum P (Fig. 9 and 10,) set a vibrating by a pallet- 
 wheel A B, connected with the axis of resistance ; and working 
 in the pallets N. It appears besides, in the Figure, that the 
 times of vibration can be changed by the mechanism T N R, 
 which raises or lowers the ball P. This then, is another re- 
 sistance, such as we sometimes want : but it is also a mean of 
 finding the quantity of resistance that a vibrating body opposes 
 to motion, when oscillating in times not those due to its length 
 as a pendulum. In other words it is a mean of measuring vis 
 inertice itself which an astounding modern writer declares 
 does not exist ! 
 
 I hasten to give a description of certain other parts relating 
 
to the measuring system : and some methods of connecting with 
 the Dynamometer the several kinds of forces it may be desirable 
 to examine. 
 
 In Plate 5, Fig. 12, AX represents a Crank or Handle with a 
 variable radius, the intent of which is to adapt a man's strength 
 to the velocity and intensity of any resistance he may have to over- 
 come. The manner is this : B is a Screw pressing on the qua- 
 drant, and fixing the arm C X to any required angle with the 
 part A C : thus determining the virtual radius of the handle. 
 
 Fig. 14, shews a method of applying to the Machine the force 
 of a man pumping : for the catch N permits the handle O to 
 rise alone, but carries round the wheel R, at every downward 
 stroke, while the fixed catch C secures all the forward motion 
 thus given. The same Figure shews, at B, the force of a man 
 in the act of rowing : for the catch M permits the lever V M 
 to recede when the man fetches his stroke, and carries the 
 wheel round when he takes it. An operation, by the bye, which 
 I think, the best mode of employing human strength, if every 
 possible advantage is taken of the method. 
 
 The 13th. Figure shews the last method I shall now offer of 
 adapting power to the Dynamometer. T S represents the Pis- 
 ton of a Steam Engine, the rod of which is formed of two bars, 
 including between them the chains F G and F D, the first of 
 which is single, merely to carry back the acting wheel ; and the 
 
20 
 
 last double, to draw round the ratchet wheel E, by the catch 
 O, at every stroke of the Piston. 
 
 I must obviate here an objection that may strike some readers. 
 This Piston T S, acts only one way, like that of an atmospheric 
 engine, a thing now quite out of date ! I answer that this figure 
 is chiefly intended to give the idea; and shew a rotatory Steam 
 Engine that might act without a fly. I will add, that it is my 
 intention some day to bring forward a method of using these 
 suspended actions, better than by a mere ratchet wheel: ""and 
 especially without incurring danger from the length of the 
 ratchet teeth, or the blow they suffer at the beginning of the 
 strokes. But of this more hereafter. 
 
 A short description will suffice for the mechanism of the 18th. 
 figure, which is intended to convert the alternate pressure of a 
 man's feet into rotatory motion, and then to measure his power. 
 To do this two catches A B, take into the teeth of the same 
 wheel M, and each catch carries an arm, P, embracing some- 
 what stiffly the boss of the wheel. The treadles have a com- 
 mon centre at E, and are fastened to the same rope going over 
 a pulley, F, so as for the depression of the one to raise the 
 other. Again, the pulling bars C D, are connected with the 
 treadles, and from the form of the catches, it is evident (since 
 the levers move with some stiffness), that the first effect of an 
 ascending motion will be to draw the rising catch out of the 
 teeth, and keep it out until arrived at its greatest height ; when 
 
21 
 
 
 
 the very beginning of its descending motion will bring the catch 
 into the teeth again, and thus carry round the wheel at every 
 downward movement of the treadle; a method this of making 
 a ratchet work without rattling upon the wheel. 
 
 The mechanism shewn in figure 19, is intended to produce 
 another of our factitious resistances ; and it serves likewise to 
 make experiments on the resistance of the air. It is a fly, meeting 
 with an equable resistance as does the fly in the striking train of 
 a clock. The wheel W, is put on the axis of resistance of the 
 Dynamometer ; and its teeth geer in those of the vertical shaft 
 L H. This latter is perforated from above, and has an open 
 mortice all along its body, which a small bar penetrates, meet- 
 ing at bottom the ring H, to which it is fastened by a pin going 
 through the mortice. Again, this ring H, is moved, downward, by 
 the rollers of the sliding bracket P, which has its motion from the 
 wheel and rack G : and finally, the leaves I K slide in the horizon- 
 tal frame; and when the machine turns would obey the centrifu- 
 gal force and fly outward ; but are withheld by the cords N O, 
 which passing over the pulleys N O, and under those L M, are 
 then fixed to the frame above L. When, now, this Machine 
 is used, and the fly made to revolve swiftly, the leaves I K, 
 oppose a certain resistance to the rotatory motion ; and if this 
 be too feeble, the key G must be turned backward, which will 
 permit the ring H to rise, and the wings I K to recede from the 
 centre. But if this resistance is already too strong, the key G 
 must be turned forward, and the wings brought nearer: between 
 
22 
 
 which extremes, a point will easily be found where the resist- 
 ance of the air will expend just power enough to balance that 
 brought into the Dynamometer through the power -axis; and 
 thus to keep the measuring weight in the posistion required for 
 any given experiment. 
 
 There remains only one part to be described as belonging to 
 this Machine. It is represented in Plate 5, fig. 17, and is a 
 graduated bar, made to fit in the holes K, of the measuring 
 cylinder I K fig. 1 : and to carry one of the arcs A A, which 
 thus serves to extend, virtually, the radius of that cylinder to 
 any required dimension. 
 
 It is now time to shew something of the manner of using this 
 Dynamometer in the measurement of forces. Let the object 
 then be to measure the power expended by a Horse in drawing 
 a Carriage. 
 
 To do this, we fix a Drum (see fig. 16,) of equal radius with 
 the measuring cylinder, on the power axis A ; and a similar 
 Drum to the resisting axis H. After firmly fixing the Machine, 
 we place the Carriage at a distance behind it in the plane of the 
 Drum H ; and carry a rope from that Drum to the Carriage : 
 on the other hand, we fill the first Drum A, with a coil of 
 rope, to which the Horse is harnessed ; and while he travels 
 in the plane of the Drum A, the scale P (fig 1,) is loaded with 
 weights, until the Carriage follows the horse's motion without 
 
23 
 
 any (or with little) agitation to the scale P : at which moment 
 the power employed is equal to one half the weight at P, multi- 
 plied by the space gone through both by the Horse and the 
 Carriage. 
 
 If it were now desired to find the power of a man turning a 
 crank or handle, we should take that given in the figure 12, 
 and fix it to the power -axis A. We should also take the fly- 
 system shewn in fig. 19, and place it on the axis -of- resistance H. 
 Then causing the man to turn the Machine, we should put 
 twice as much weight into the scale P, as his strength was 
 thought ahle to bear. Then if he thought the work too 
 heavy, we should draw inward the leaves of the fly, and take 
 away part of the weight P, until the man were satisfied he 
 could work with convenience : and when, as before, the weight 
 P should overcome the resistance of the fly I K, without either 
 rising or falling, (sensibly) then the power expended would be 
 one half of the weight P, multiplied by the space described by 
 the man's hand in the act of turning the handle. 
 
 It may occur to some of my readers that in these experiments 
 the whole effect is not actually measured: since the space describ- 
 ed by the horse or the man's hand, must be determined after the 
 experiment. I answer that these quantities, necessarily variable, 
 must bear an inverse proportion to the weight 'P : and in all 
 cases, this weight multiplied by that space, must give the power 
 or momentum required. Besides, it is most easy to add a piece 
 
24 
 
 of mechanism that shall count the number of turns, and express 
 them in space, by the inspection of a graduated scale. Nor 
 need we stop here. The duration, in time, of any experiment, 
 may also be recorded by the Machine itself. These are things 
 so naturally connected with the subject, that I cannot feel it 
 necessary, with so much before me, to attempt exhausting them. 
 But this I engage to do : if any serious dfficulty should actually 
 stop any reader in this career of investigation, I will obviate 
 such difficulty at some convenient future period. And mean 
 while those persons who have aptitude for such subjects, will 
 find in this Machine, ample scope for extending their enquiries ; 
 and comparing many mechanical realities with the deductions 
 of Theory, thus amending and conciliating the conclusions both 
 of Theory and Practice. 
 
 I have said above, that the weight or spring acting on the 
 measuring clylinder at P, must be equallized : but in reference 
 to some applications of this Machine to real use, I would modify 
 that precept a little. I should, indeed, always like the princi- 
 pal action to be of a constant nature : with a supplementary 
 part of less intensity, prepared to add something to the former ; 
 and this, for the purpose of meeting spontaneously the case of 
 any unexpected addition of the moving power. Thus in fig. 1, if 
 P be a weight nearly adapted to a given resistance, I would (to 
 prevent accident, from its being overraised by any sudden jerk 
 of the power,) hang one or more heavy chains under the scale, 
 which drawn from the ground to a certain length, would add 
 
25 
 
 a known quantity to the measuring power ; and transmit with a 
 certain softness to the work, the unequal action of the mover. 
 
 One word on the friction of this Machine. All friction must 
 of course be avoided as much as possible ; but as it will be nearly 
 the same in every class of experiments, it is not of great im- 
 portance. The same may be said of the vis inertia of the parts, 
 in convulsive motions. The parts would, of course, be made as light 
 as a proper strength would permit. My mechanical readers will 
 easily supply these small items of foresight ; to anticipate the 
 whole of which would make this Work interminable. 
 
OF A NEW KIND OF 
 
 BARREL SPRING, 
 
 To lengthen the going of Clocks, Jacks, r. 
 
 ALTHOUGH this invention does not properly consitute a new 
 Spring, yet it produces effects both new and important. It pro- 
 tracts almost indefinitely the action of a barrel Spring, and thus 
 reduces considerably the number of wheels in a clock or other 
 spring -driven machine. This effect is produced by setting the 
 two ends of the spring at variance ; or making them act one 
 against another : for as these opposite tendencies can be made 
 nearly equal, one end of the spring will be wound up almost as 
 much as the other end runs down : thus prolonging the effect in 
 any desired proportion. It will be making known the principle, 
 to describe the first motion of a clock founded upon it. 
 
 In Plate 7> fig- 1, A is the spring barrel, to which is fixed a 
 wheel, B, of 96 teeth, working in E, a pinion, of 17- E is 
 another wheel of 92 teeth, working in F, a pinion of 22 : both 
 pinions being fixed on the same arbor, I G. The smaller wheel 
 E, turns on a round part of the axis H D ; and is connected 
 with its motion in the backward direction only, by a ratchet 
 wheel R, fixed on a square part of the same arbor. As usual, 
 this latter has a cylindrical boss within the barrel A, to which 
 the inner end of the spring is hooked ; as its outer end is, to 
 
27 
 
 the rim of the barrel ; and thus does the wheel B (when the 
 clock is wound up) tend to turn forward as shewn by the arrow 
 B ; while the wheel E, tends to turn backward in the direction 
 of E, the second arrow. But these opposite tendencies are not 
 equal; because the wheel B is larger, and acts disadvantage- 
 ously on C, the smallest pinion ; while the wheel E is smaller, 
 and acts to advantage on the larger pinion F : so that there is 
 a decided tendency in the whole to turn backward. Now, to 
 find precisely what is the effect of that tendency, we observe 
 that when the barrel and the larger wheel B, have made one 
 revolution round the common axis H D, the pinions C and F 
 will both have made -^ of a revolution (being the quotient of the 
 division of the wheel B by the pinion C :) and since the larger 
 pinion of 22 teeth, works in the smaller wheel of 92 teeth; this 
 latter wheel in the same time will have made ?F of ^- of a re- 
 
 17 jZ 
 
 volution, or 1,350 of a turn very nearly. The difference then 
 between this quantity and unity, namely the decimal 0,350, 
 is what the spring has really gone down during one turn of 
 the barrel. And as the whole number of coils in the spring are 
 10, the number of turns of the barrel to uncoil it entirely, will be 
 or ~3&o e< l ua l to 28,57 nearly: instead of ten revolutions 
 
 which it would have been on the common principle. 
 
 It is almost superfluous to add that this prolongation of the 
 time might have been greater, had I not been confined to 
 the above numbers, for want of others more nearly alike 9 and 
 having a common difference, on my engine. 
 
28 
 
 An important remark here presents itself, viz. that the best 
 properties of this invention are unattainable by the use of the 
 common geering the friction of whose teeth would have ab- 
 sorbed the small rotatory tendency thus retained ; and in which 
 system, also the working diamenters of the wheels could not have 
 been defined with sufficient exactitude. This then, is one of 
 the cases in which (as I have observed in a former work) my 
 late Patent System of Geering has ' ' given rise to machines that 
 could not have existed without it," which it does by possess- 
 ing exclusively the property of realizing (sensibly) the whole 
 calculated effect ; and working without commotion or assignable 
 friction. It may please some of my readers to be informed that 
 this System, and the means of executing it in every dimension, 
 will hold a prominent place in some future page of this essay. 
 
 Referring again to the figure 1 , the teeth X X, Y Y, are 
 there placed to give a first idea of this principle : and they 
 are unaccompanied by others, to avoid the confusion of lines 
 that would have arisen from attempting to shew all the teeth, 
 in their due position, on so small a scale. These things will 
 claim all our attention when the System itself comes under 
 examination. 
 
 The above representation of this Machine may leave a tech- 
 nical difficulty on the minds of clock makers relative to the 
 winding up of 'this spring; which, in the present state of things, 
 will suspend, for the time, it's action on the pendulum: for in 
 
29 
 
 order to effect it, (in a reasonable number of turns) the intro- 
 duction of the key must, by a proper check-piece, be made to 
 stop the wheel B, and leave it again at liberty when the key is 
 taken out : in which case ten turns of the key will effect the 
 winding, although the Machine should be calculated to give out 
 forty turns in the uncoiling of the spring. But if the wheels B 
 and E had changed places ; that is, if E had been fixed to the 
 barrel A, and B been connected with the ratchet wheel R, 
 then the act of winding up would have taken place in the oppo- 
 site direction ; or in that which tends to keep up the motion of 
 the pendulum, in which case, however, the machinery of the 
 clock must have borne the whole stress of the spring during the 
 act of winding, instead of the small portion it sustains when 
 the two ends counteract each other. 
 
 But I anticipate another objection to this method of employ- 
 ing a barrel spring : which is the inequality of stress, when the 
 spring is much or little wound. The answer is, that many 
 clocks and watches are made to go well without fusees ; either 
 by modifying the thickness of the springs, or employing only a 
 few of the middle coils. My Invention may, perhaps, help to 
 nurse this System to perfection : if not, its influence will be the 
 more confined, but in no wise destroyed. 
 
30 
 OF 
 
 A PARALLEL MOTION, 
 
 Being a combination of ike Crank with the Epicycloid. 
 
 A B, Plate / fig- 2 and 3, is a ring or wheel fixed to the 
 frame CD; and having all round it's inside, teeth directed to 
 the centre. F is a wheel of half the diameter, and exactly half 
 the number of teeth of the wheel A B. It tarns on a Crank- 
 arm, E F, whose radius is equal to one quarter of the diameter 
 of the fixed wheel A B in the centre of which the axis of 
 this Crank finds it's due position. The latter, therefore, so 
 conveys the wheel F round the inside of the fixed wheel A B, 
 that the teeth of both are constantly geering to a proper depth : 
 and a stud being fixed on the face of the wheel F, opposite the 
 middle of any tooth, a, directly over the centre of the Crank E, 
 this stud describes the perpendicular diameter of the large 
 wheel ; and will either receive motion from the rod R of a 
 Steam Engine Piston, so as to give the fly I K, a rotatory 
 motion; or communicate to a Pump-piston a reciprocating mo- 
 tion, drawn from die rotatory one of the fly, when that is the 
 effect desired to be produced. 
 
 This Invention will be remembered, as having procured me a 
 
 remunerating Medal from the late Xapoleon Bonaparte, then 
 first Consul of the French Republic. That period, however, 
 
31 
 
 (1801) was not the real date of this production, although then first 
 made public. I have proof, on the contrary, of its existence with 
 me several years before ; and it is generally ascribed to me by 
 the publicists. I might quote in particular Doctor Gregory : 
 who likewise mentions its having been executed by Messrs. 
 Murray and Wood, of Leeds, subsequently to it's exhibition at 
 Paris. The Doctor commits, however, a small error in calling 
 me an Anglo-American ; but this is accounted for by my then 
 living in a country where to be an Englishman was itself a crime ! 
 and where some kind friends, wishing to hide me from the re- 
 lentless decrees of the day, felt justified in using this sort of pious 
 fraud in my favour : a resource from which, though I did not 
 authorize it, I reaped no small advantage ; and still think of 
 with gratitude, though not with unmixed approbation. 
 
 I think it a duty more imperious than agreeable, to expostu- 
 late a little with Messrs. Lanz & Betancourt, on their apparent 
 partiality in giving an account of this Machine. In their work 
 on the construction of machines, art. 97, page 37, they make 
 M. de la Hire the inventor of it, by the terms in which they 
 introduce his treatise on Epicycloids : and they leave me the 
 thread -bare merit of having "presented a model of this move- 
 ment at the last exposition but one/' &c. Now, although I do 
 not attach great importance to this kind of misrepresentation, 
 I cannot but observe, that neither my Machine or their descrip- 
 tion of it can be called a Theorem ! nor especially a theorem 
 relating solely to the Epicycloid, as M. de la Hire's was. These 
 
32 
 
 Gentlemen knew that he insisted principally on the application 
 of this curve to the teeth of wheels, with which my Invention 
 has nothing to do. On the contrary, my Machine is a combi- 
 nation of two curves at least, on which de la Hire says abso- 
 lutely nothing. Is this then inadvertency ? or is it uncandid 
 nationality ? I hope, the former. 
 
 A further remark on the utility of this System as a first 
 motion, may be of use in this place. It respects the geering of 
 the fixed and moveable wheels A B, and F, on the perfection 
 of which depends the truth of the statement, that the stud, a, 
 describes a diameter of the large wheel. Now, perfection is 
 too much to be expected from common teeth when of the ne- 
 cessary strength ; so that my Patent Geering is an indispensable 
 complement to this Invention : as by its use, the principle is 
 made practically true; this line becoming really straight, and 
 this motion, under proper circumstances, being unattended with 
 noise or commotion. In a word, I cannot move a step in this 
 mechanical field, without meeting with instances where the 
 new System shews its superiority to the old : whence it becomes 
 a duty for me to commence the consideration of this subject in 
 the very next part of this publication. 
 
33 
 
 OF 
 
 A SYSTEM OF CONCENTRIC PULLEYS, 
 
 Already known as White's Patent Pulleys. 
 
 THESE Pulleys have been frequently described since I first 
 entered my specification at the Patent Office. The Authors of 
 the Encyclopedia Britannica ; the Rev. Mr. Joyce, in his ju- 
 venile philosohpy ; and Dr. Gregory in his mechanics, have all 
 adverted to them. In the latter work, I find the following quo- 
 tation from my own description, thus introduced : 
 
 A very considerable improvement in the construction of 
 pulleys has been made by Mr. James White, who obtained a 
 Patent for his Invention, of which he gives the following des- 
 cription : " Fig. 4, Plate 7> of this work, shews the Machine, 
 "consisting of two pullies, Q and R ; the former fixed, the 
 "other moveable. Each of these has six concentric grooves, 
 " capable of having a line put round them, and thus of act- 
 " ing like as many different pulleys having diameters equal to 
 " those of the grooves. Supposing then, each groove to be 
 " a distinct pulley, and that all these diameters were equal, it 
 " is evident, that if the weight 144 were to be raised by 
 " pulling at S, till the pulleys touched each other, the first 
 * ' pulley must receive the length of line as many times as there 
 i ' are parts of the line hanging between it and the lower pulley. 
 
 G 
 
34 
 
 <c 
 
 In the present case there are 12 lines, b, d, f, &c. hanging 
 between the two pulleys, formed by its revolution about the 
 six upper and six lower grooves. Hence as much line must 
 pass over the uppermost pulley as is equal to 12 times the 
 distance of the two. But, from an inspection of the figure, it 
 is plain that the second pulley R S, cannot receive the full 
 quantity of line by as much as is equal to the distance betwixt 
 it and the first. In like manner, the third pulley receives less 
 than the first, by as much as is equal to the distance between 
 " the first and the third ; and so on to the last which receives 
 " only ^- of the whole : for this receives it's share of line n, 
 " from SL fixed point in the upper frame which gives it nothing: 
 " while all the others in the same frame receive the line 
 " partly by moving to meet it, and partly by the line coming 
 " to meet them/' 
 
 " Supposing now these pulleys to be equal in size, and to 
 " move freely as the line determines them, it appears from 
 l< the nature of the system, that the number of their revolu- 
 " tions, and consequently their velocities, must be in propor- 
 " tion to the number of suspending parts, that are between the 
 " fixed point above-mentioned, (n) and each pulley respec- 
 " tively. Thus the outermost pulley would go twelve times 
 " round in the time that the pulley under which the part 
 u n of the line passes, (if equal to it) would revolve only once ; 
 " and the intermediate times and velocities would be a series 
 ic of arithmetical proportionals of which, if the first term were 
 
f( 1, the last would always be equal to the whole number of terms. 
 " Since then, the revolutions of equal and distinct pulleys are 
 " measured by their velocities, and that it is possible to find any 
 " proportion of velocity on a single body running on a centre, 
 " viz. by finding proportional distances from that centre; it 
 " follows, that if the diameters of certain grooves in the same 
 ' ( body be exactly adapted to the above series, (the line itself 
 ' f being supposed inelastic and of 110 magnitude) the necessity of 
 " using several pulleys in each frame will be obviated, and with 
 " that some of the inconvencies to which the use of the com- 
 " mon pulley is liable." 
 
 " In the figure referred to the coils of rope, by which the 
 weight is supported, are represented by the lines a, b, c, &c. 
 a is the line of traction commonly called the fall, which passes 
 over and under the proper grooves, until it is fastened to the 
 upper frame just above n. In practice, however, the grooves 
 are not arithmetical proportionals ; nor can they be so, for the 
 diameter of the rope employed must be deducted from each term, 
 without which, the small grooves to which the said diameter 
 bears a greater proportion than to the larger ones, will tend to 
 rise and fall faster than the latter, and thus introduce worse 
 defects than those which they were intended to obviate." 
 
 " The principal advantage of this kind of pulley is, that it 
 destroys lateral friction, and that kind of shaking motion 
 which are so inconvenient in the common pulley ; and lest, says 
 
36 
 
 Mr. White, (I quote Dr. Gregory) this circumstance (of a 
 long pin) should give the idea of weakness, I would observe, 
 that to have pins for pulleys to run upon, is not the only, nor 
 perhaps the best method : but that I sometimes use centres fixed 
 in the pulleys, and revolving on a short bearing in the side of 
 the frame, by which strength is increased, and friction much 
 diminished : for to the last moment of duration, the motion of 
 pulley is circular, and this very circumstance is the cause of 
 it's not wearing out in the centre as soon as it would, as- 
 sisted by the ever increasing irregularities of a gullied bearing. 
 These pullies when well executed, apply to Jacks and other 
 Machines of that nature with great advantage : both as to the 
 the time of their going and their own durability : and it is possible 
 to produce a System of pulleys of this kind, composed of six or 
 eight parts only, and adapted to thepocket, which by means of a 
 skain of sewing silk, would raise more than a hundred weight." 
 
 There are several real and solid advantages attending the use 
 of this pulley ; some of which are only hinted at in this des- 
 cription. I have thought, therefore, it might be useful to in- 
 troduce here an account of some trials which the System under- 
 went a few years ago at Portsmouth, at the request of an 
 Officer of the Navy, who had re -invented it with some ingenious 
 additions to my ideas. Not being at present in correspondence 
 with that Gentleman, I hardly think myself at liberty to mention 
 his name ; but fully so to give an extract from the report which 
 followed these experiments in which the superiority of the 
 
37 
 
 System in respect of power, is made evident, although some 
 less favourable circumstances prevented its adoption on that 
 occasion. 
 
 " With a view to comparison, it was settled with Lieutenant 
 *' S. that .his blocks should be made to correspond with the 
 " treble and double 16 inch blocks of a 24 gun ship, which 
 " carry a 4J inch rope. The sheeves in the new blocks are fixed 
 " upon the pin, revolving therewith, and are of different di- 
 " ameters proportioned to the velocity of the parts of the rope 
 " that pass over them ; they are also reeved with a double 
 " rope so that there are two grooves of each size, the diameter 
 " of the smallest groove in this tackle being 2-^, and of the larg- 
 " est 15 inches. The diameter of the sheeves of the common 
 " blocks would have been (as usually made) 91 to the bottom of 
 " the grooves, but were reduced at the request of Lieutenant S. 
 * ' in the treble block to 8i , and in the double block to 81, in order 
 ' ' that the sum of the diameters of the sheeves in each tackle 
 " should be the same. The Lieutenant intending in the first 
 " instance, to have used a roller under the pin, for the purpose 
 " of diminishing friction, but afterwards laying aside this idea 
 66 on account of it's complication, was the reason that he had 
 " not made his sheeves in the same proportion with the common 
 " blocks : the weigiit and length of the respective blocks are 
 " as follows : 
 
 fl 
 
38 
 
 Weight. Length. 
 
 Lieutenat S.'s treble blocks . 131 Ibs. ... 24 Inches. 
 
 Common ditto ... 7$ ... 16 ,, 
 
 Lieutenant S.'s double block 73 ,, ... 21 ,, 
 
 Common ditto ... 60 ,, ... 16 ,, 
 
 Lieutenant S.'s single block 22 ,, . . . 17 ,, 
 
 Common ditto . . 34 ,, ... 16 ,, 
 
 " Lieutenant S.'s blocks were reeved with a 2J inch double 
 " rope, and the common block with a 4^ inch single rope, 
 " and both tackles suspended from a beam, and their respec- 
 " tive falls let over the single blocks, so as to keep the weight 
 " applied as a power, just clear of the weight to be lifted, thus 
 (( forming a power of six to one ; the following experiments 
 c< were made : 
 
 Weight very Power required Power required 
 
 slowly lifted. with Lieutenant S.'s blocks. with the common blocks, 
 
 fts. fts. fts. 
 
 336 88 124 
 
 672 169 252 
 
 1344 312 448 
 
 2688 588 808 
 
 5376 1101 1344. 
 
 * ' After reeving the common blocks with a 3^ inch rope in lieu 
 " of a 4J inch rope, it was as follows : . 5376 . .1101 . . 1232. 
 
 " It must be observed, that the double 2J inch rope in Lieu- 
 
" tenant S.'s blocks, is not of equal strength with the single 4J 
 { ' inch rope first used in the common blocks ; and that his blocks 
 ' *" had an undue advantage in the first experiment over the com- 
 i( mon blocks, in respect to the pliability of the rope. The 
 " rope should therefore, be taken larger in the one or smaller 
 * in the other case, on this account : The common blocks were 
 " reeved in the last experiment, with a 3f inch rope, which is 
 " as near as may be of the same strength as the double 2 
 " inch rope. 
 
 " In these experiments it was observable, that the tar was 
 ' ' much more squeezed out of the parts of the rope that passed 
 " over the smallest sheeves in Lieutenant S.'s blocks, than out 
 " of those passing over the larger sheeves, or out of those pas- 
 ing over the sheeves of the common blocks ; by which, as well 
 as by the nature of the thing, we judge that with blocks re- 
 quiring such small sheeves, the ropes would be more crippled 
 and broken than by the common blocks, especially if any 
 constant strain or weight in motion, as on ship board, should 
 be held by them. In regard to our opinion of the merits of 
 the blocks proposed by Lieutenant S. compared with common 
 blocks, we beg leave to submit, that the mechanical prin- 
 ciple of them is very inviting, and it is not to be won- 
 dered that an ingenious person should pursue the idea ; yet 
 allowing there would be a saving of power, which is attained 
 in so great a degree with the common blocks, but con- 
 sidering the greater complication, weight, and expence of 
 
 tt 
 tt 
 tt 
 tt 
 1 1 
 tt 
 tt 
 it 
 
40 
 
 (< these blocks, and their greater disposition to cripple the ropes, 
 " we do not perceive any application of them on ship board, 
 
 (< 
 
 " 
 
 for which we could recommend them in preference to com- 
 mon blocks ; neither do we perceive any purposes on shore, for 
 the services of the dock yards in which to recommend 
 their application in preference to the other powers in use." 
 
 To this account of the result of these experiments, I beg 
 leave to add what seems to be a great improvement of this 
 System : namely, a method by which the diameters of the 
 larger pulleys are considerably lessened ; and thus the princi- 
 pal, if not the only objection, obviated. It has been before ob- 
 served, that the larger pulleys, as Q R, are the ultimate terms 
 of an arithmetical progression, beginning at unity ; and that 
 consequently they cannot be very small, even though the first 
 terms should be so. If a first pulley were only one inch in di- 
 ameter, the twelfth pulley would be twelve inches,- where we 
 see a large and inconvenient difference. But this evil I now 
 
 
 
 obviate, by placing at the beginning of the series, one or more 
 loose pulleys, over which to reeve the cord, before the con- 
 centric or fixed grooves begin ; thus lowering the ratio of the 
 progression, and keeping the larger pulleys within bounds. 
 For example, the smallest fixed pulley (supposed as before, to 
 be one inch in diameter) I now make the second of the series 
 instead of the first : and therefore, the second fixed pulley is to 
 the first as 3 to 2, instead as being as 2 to 1 ; for the same 
 reason, the third fixed pulley is to the second as 4 to 3 ; and 
 
41 
 
 in a system of 12 pulleys, (with one loose one) the respective 
 terms will be as follows : 
 
 Terms 1 2- 3 4 -5 -6 7-^89 101112 
 
 3 . 4 jL. A- . II. J 
 
 lOOSe 1 ; i~ 2~; ~2~'lT'~2~'ir> 2' 2 ' 2' 2' 2 
 
 or 6 inches for the largest pulleys, instead of 12 inches given by 
 the last progression. 
 
 So likewise, if we take two loose pulleys (which will not add 
 much to the complication of the Machine) and make the third term 
 1 inch, the fourth will become -^-, shewing the ratio of the pro- 
 gression to be ^-, so that the series of 12 terms will stand thus : 
 
 Terms, 1 2 3 4 -5 6 7 8 9 10 11 12 
 
 -. 4 5 6 7 8 9 10 11 12. 
 
 loose; loose; 1; -3-5-3-; --: T' T' T> T T T' )r > 
 four inches for the largest groove in the concentric part of the 
 System. 
 
 Now we saw before, that the first and last pulley were in 
 diameter to each other, as 1 to 12 ; whereas, here, with only 
 two loose pulleys, these extremes are but as 1 to 4 : dimensions 
 much more convenient and manageable. The 5th. figure of 
 the Plate 7> is intended to shew graphically, the effect of this 
 modification of the principle. In that figure, if the line a, be the 
 diameter of the first pulley, that of the sixth pulley will be shewn 
 by the line b c ; but if the same line a be made the second pulley, 
 the diameter qf the sixth will be shewn by the line e d ; only 
 '- of the former. And in fine, if the same a, be the third pul- 
 ley, the sixth will have it's diameter reduced to the line f g, 
 
 i 
 
42 
 
 only one half of what it was in the first case. In a word, the 
 more loose pulleys are put before the fixed ones begin, the 
 nearer to cylindrical will the general form become ; and the 
 more conveniently may pulleys be used for general purposes. 
 I might even assert, that if one, or at most two loose pulleys 
 had been used in the above-mentioned experiments, the result 
 would have been as favourable to the System, with respect to 
 the weight of the tackle and stress on the ropes, as it was in 
 respect of power ; where it's advantages were important and 
 undeniable. 
 
OF 
 A POWER-WHEEL, 
 
 Turned by heated Air, Gas, -c. 
 
 JL HIS Wheel (see Plate 8, fig. 1,) is technically called a 
 Bucket -wheel. It is plunged almost entirely in water, oil, 
 mercury (or other heavy fluid) contained in the vessel A B. 
 It's axis carries a waved wheel a b, on which rolls a friction- 
 pulley p, running on a pin in the mortice of the bar c d. This 
 bar works the pump f ; which by the descent of it's loaded 
 Piston, drives cold air (or gas) into the tube g, communicating 
 with several collateral ones placed across the vessel, so as to 
 convey the air to h, below and beyond the centre of the wheel. 
 A fire being made at F under this vessel, the water (or other 
 fluid) is brought to a proper heat ; and if then the pump f, be 
 made to give a stroke or two, air will be forced from the tubes 
 at h, which having been heated in the passage, will bubble up 
 into the buckets h, i, k, &c. and turn the wheel so as to per- 
 petuate it's own supplies from the Pump, and furnish surplus 
 of power for other purposes. This results from the fact, that 
 air (for example) in rising to the temperature of boiling water, 
 expands, under the pressure of the atmosphere, to about three 
 times the volume it occpied at the mean temperature : so that 
 it resists the entrance into the vessel as unity, and acts (when 
 
44 
 
 heated) as 3 : leaving a power of two, in the form of a ro- 
 tatory motion. 
 
 It will occur to many readers, that azotic gas or nitrogen, 
 might be used with advantage to turn this wheel : only adding 
 to the Machine a long returning tube, leading from the top of 
 the vessel, through air or water, to the suction valve of th,e 
 pump f ; and that in order to bring down the temperature of the 
 gas from the heat it had acquired in the vessel, to the mean 
 temperature ; at which this gas is said to occupy only 7 of the 
 space it fills when at the heat of boiling water. 
 
 I have now to observe that this invention was executed in 
 1794, of which abundant proof remains. Since then, it has 
 been proposed by other persons, and is I think, patentized 
 either in France or England : but a different method is employed 
 of introducing the cold air, namely an inverted screw of Archi- 
 medes, whose manner of working I do not entirely recollect. 
 What I here wish to observe is, that this concurrence of idea 
 between others and myself, gives me no pain ; since it would 
 be more strange if it did not happen, while so many active 
 minds are ransacking nature for the very purpose of unveiling 
 her secrets. Only I think it incumbent upon me to use every 
 method, consistent with truth and honour, to avoid being 
 thought unjust enough to purloin other people's ideas, and call 
 them my own. 
 
45 
 
 OF 
 
 AN EQUABLE PUMP, 
 
 Or Machine for raising Water without interruption or concussion. 
 
 TfflS Machine is represented in Plate 8, fig. 2 and 3. It is 
 composed of two barrels A B, both of them forming part of the 
 column of water to be raised ; connected together by a crooked 
 tube C, of equal diameter, out of which the lower Piston -rod passes 
 through a stuffing box into the air : as does the upper Piston- 
 rod at D, where the column leaves the Pump to pass up- 
 ward. The two Pistons fixed to the rods E and F, are of the 
 bucket kind ; made as thin and light as possible ; their valves 
 opening upwards and their motions being such, generally, that 
 when one of them is drawn up, the water rises through the 
 other, then descending : But here lies both the novelty and 
 utility of this Machine ; these upward and downward motions 
 are not reciprocal : Both Pistons fall faster than they rise, and 
 thus leave an interval of time when they both rise together; 
 during which their valves, respectively, close by their own 
 weight before the column of water falls upon them. In such 
 manner, indeed, that the column never falls at all. By this 
 important arrangement, the work is constantly going on, and 
 no commotion occurs to absorb Power uselessly, or to destroy, 
 prematurely, the Machine; circumstances which constantly at- 
 tend every Pump Machine acting by merely reciprocal motion. 
 
This non -reciprocity then, I produce by several methods ; one 
 of which (perhaps the most easily understood) is that shewn in 
 fig. 2 : There, A B are two friction -rollers, made as large as 
 possible, rolling on the curves C X, the ascending and descend- 
 ing parts of which are essentially unequal. For example, the 
 rising part of the curve occupies ~ of the whole circumference ; 
 and the falling part y only ; so that both curves recede from 
 the centre at the same time, during -g- of a revolution, 
 at the two opposite positions, A C and X Y. Applying then, 
 these curves and levers to the Pump -barrels represented in fig. 3, 
 we obtain that continuity of uniform motion, which is necessary 
 to doing the greatest quantity of work with the least power ; 
 and to securing the greatest durability of the Machine. Having 
 hinted at a minimum of power, I must add here that this 
 Machine appears to promise that result, much more credibly 
 than any reciprocating pump whatever ; especially if to this con- 
 tinuity of power we add a certain largeness of dimension that 
 shall produce the required quantity of water, with the slowest 
 possible motion of each particle ; and even here this continuative 
 principle helps us much ; since pistons and valves of the largest 
 dimensions may be used without introducing any convulsive, 
 or (what is synonymous) any destructive effects. 
 
 One particular remains to be noticed in fig. 2. It relates to 
 the means by which the perpendicularity of the motion in the 
 Piston-rods is secured. The arcs M are portions of cylinders 
 having the bolts Z, for their centres, and which, rolling up 
 
47 
 
 and down against the perpendicular plane O N, secure a similar 
 motion to the bolts. The tenons P, are cycloidal, on their up- 
 per and lower surfaces ; and work in square or oblong holes in 
 the plane N O, being kept in their holes by the action of the 
 two springs on a pin let through these tenons : and thus is the 
 motion of the point Z of the levers M B, a perpendicular one ; 
 and that of the friction rollers A B, very nearly so. 
 
 My object in this work, is to make known the principles, and 
 some of the forms of these Inventions, but my limits will not 
 permit their being dilated on ; else I could give several more 
 useful forms of this Machine: but, to make room for other sub- 
 jects, I must hasten forward reserving to some future period, 
 many hints respecting the adaptation of those ideas to particular 
 cases. Those of my readers who love to speculate on the 
 doctrine of permutations , will anticipate how much may be done 
 by the combination of a hundred Machines with each other : and 
 they will give me credit for detached items of knowledge 
 useful in themselves, though too minute to be severally brought 
 forward. Should, however, the degree of patronage I have 
 already experienced, be proportionably extended as the work 
 advances, / can and will follow it up with many useful hints, 
 tending to shew the extent of some of my present subjects, and 
 the amplitude of the sphere in which they roll. 
 
 It should be observed, in concluding this article, that the 
 present Machine was executed in France, in 1793, and also 
 
48 
 
 proposed to the Government, as a substitute for the celebrated 
 Machine of Marly. In the report then published, it was pre- 
 ferred to the whole multitude of former projects ; but left in equili- 
 bria with one modern Machine, a competition which prevented 
 it's adoption for the moment and indeed till I was glad to 
 escape the notice, instead of courting the favour of the then 
 rapidly succeeding governments. 
 
49 
 OF 
 
 A SIMPLE MACHINE, 
 
 For Protracting the Motions of Weight -Machinery. 
 
 , 
 
 f 4- 
 A, Plate 8, be the barrel-wheel of a Clock, or other 
 
 Machine, already in use, and driven by a weight ; and let the 
 similar barrel B be added to the former ; the motion of both 
 being connected by the unequal wheels C D. The rope or chain 
 E F, is then led from the barrel A under the pulley P to the bar- 
 rel B : By which arrangement, when the weight has occasi- 
 oned one revolution of the barrel and wheel A C, those BD, will 
 have made a lesser portion of a revolution in the ratio of the 
 wheel C and D ; (namely as 22 to 24,) and that motion will 
 have taken up of the line which the barrel A has given off. 
 By these means, the motion of the whole may be prolonged 
 almost indefinitely. This System may appear to some persons 
 open to the objection that the friction of the wheels C D, will 
 absorb so much of the power, as to leave the rotatory tendency 
 too feeble for it's intended purpose. But I again take refuge in 
 the well proved property of my patent geering, of not im- 
 peding (sensibly) the motion of any Machine in which it is used. 
 
 Should it further be suggested, that this is only an awkward 
 parody on the diffential wheel andaxle, ascribed by Dr. Greg- 
 
50 
 
 ory (in the introduction to his work, page 4,) to the celebrated 
 George Eckhardt : I would answer, that I made that invention 
 also ; though doubtless after Mr. Eckhardt ; and especially 
 after the date of the figure given by the Doctor, as coming 
 from China, ' ' among some drawings of nearly a century old ; ' ' 
 Of course then, I do not pretend to priority of invention : but 
 truth herself authorises me to say, that I did invent this Ma- 
 chine also, in the night between the Vjth. and ISth. of January, 
 1788, and drew it in bed by moonlight, that it might not escape me ! 
 It was the result of a previous^ of close thinking : and of the con- 
 clusion I then drew, that in whatever way, slowness of motion 
 is obtained by the connection of two movements, power is in- 
 variably gained for the same reason, and in the same proportion. 
 The fact is, that all my ideas respecting differential motions, 
 have flowed from this source ; as will be evident to the attentive 
 reader of these pages. 
 
51 
 OF 
 
 AN INSTRUMENT 
 
 For drawing Portions of Circles, and finding their Centres by 
 
 inspection. 
 
 J.T is a known property of an angle such as g d f (plate & 
 fig. 1) when touching two fixed points g f, and gliding from 
 one of these points to the other, to describe a portion of a circle 
 g d f . My object in this instrument is to determine, by in- 
 spection, the radius of such circle in all cases. 
 
 To do this, I connect with the jointed rule m d n, another 
 rule like itself but shorter g e f, so as that the figure g d e f 
 shall be a perfect parallelogram : and I then say that knowing 
 the distance of the points d and e, (the distance d f being given) 
 I know the radius of the circle of which g d f is a portion. To 
 prove this, a little calculation is necessary : In the circles A B 
 and a b (fig. 6) draw the lines E D ; f d, d g, g f, g e, andg* _D; 
 and bearing in mind the known equation of the circle, let d n= 
 oc, g n = y ; and g D = a, the absciss, ordinate, and radius respec- 
 tively. The equation is 2 a x x 2 = y 2 : from which we get = 
 the denominator of this fraction being the line d e. But 
 
 2x 
 
 further its numerator (y 2 -f- # 2 ) is equal to the square of the 
 chord g d of the angle E D g, which chord I call c. This 
 gives a = jg^yj; from which equation we derive this propor- 
 
52 
 
 portion a : c : : c : line d e ; Putting then the chord c 1 
 (one foot for instance) this proportion becomes :!::!: 
 ; whence we draw this useful conclusion, that, whatever 
 portion of a foot is contained in the line de, (expressed by a 
 fraction having unity for its numerator) the radius of the circle 
 will be expressed in feet by the denominator of that fraction. 
 Thus if the line d e, be 1 inch or ^ of a foot (and the line g d 
 or df be 1 foot) the radius of the circle will be 12 feet ; and so 
 for every other fraction. Now in the instrument itself the two 
 points d and e, are connected by a micrometer -screw (not here 
 drawn) of the kind described in a subsequent article, and by which 
 an inch is divided in 40,000 parts, each of which therefore is the 
 3333 38 &c. part of a foot : so that if the distance d e, were only 
 one of these parts, we should produce a portion g d f of a cir- 
 cle of 3333.33, &c. feet radius being more than half a mile. 
 
 I had omitted to observe, that the points or studs, against 
 which the rulers m n slide, to trace the curve (by a style in the 
 joint dj that these studs I say are fixed to a detached ruler o p, 
 laid under the parallelogram on the paper, and having two 
 stump points to hold it steady : one of the studs being moveable 
 in a slide, in order that it may adapt the distance f g, to any 
 required distance of the points d e : We note also that the dotted 
 curve g d f is not the very circle drawn, but one parallel to it and 
 distant one half the width of the rulers. In fact the mortices of 
 these rulers are properly the acting lines, and not their edges. 
 I expect, for several reasons, to resume the subject of this in- 
 strument before the work closes. 
 
53 
 OF 
 
 AN INCLINED HORSE WHEEL, 
 
 Intended to save room and gain speed. 
 
 JM.Y principal inducements for giving this Wheel the form 
 represented, by a section, in fig. 3, (see Plate 9) were to save 
 horizontal room ; and to gain speed by a JVJieel smaller than a 
 common horse-walk, and yet requiring less obliquity of effort 
 on the part of the horse. With this intention, the horse is 
 placed in a conical Wheel A B, more or less inclined, and not 
 much higher than himself: where, nevertheless, his head is seen 
 to be at perfect liberty out of the cone as at C. The horse then 
 walks in the cone, and is harnessed to a fixed bar introduced 
 from the open side where, by a proper adjustment of the traces, 
 he is made to act partly by his weight, so as to exert his 
 strength in a favourable manner. This Machine applies with 
 advantage where a horse's power is wanted, in a boat or other 
 confined place : and it is evident, by the relative diameters of 
 the wheel and pinion AB and D, (as well as by the small di^ 
 ameter of the wheel ) that a considerable velocity will be ob- 
 tained at the source of power, whence, of course, the subse- 
 quent geering to obtain the swifter motions, will be proper 
 tionately diminished. 
 
54 
 
 OF 
 
 A DIFFERENTIAL COMBINATION OF 
 
 WHEELS, 
 
 To count very high numbers, or gain immense power. 
 
 J.N fig. 2, of Plate 9, (which offers an horizontal section of 
 the Machine), A B is an axis, to the cylindrical part of 
 which the wheels C D are fitted, so as to turn with ease in 
 either direction. Each of these wheels, C and D, has two rims 
 of teeth, a b, and c d; and between those b d are placed an 
 intermediate pinion w, connected by it's centre with the arm a?, 
 which forms a part of the axis A B. There is likewise a fourth 
 wheel or pinion z, working in the outer rims a c of the wheels 
 C and D. It appears from the figure itself, that the action of 
 this Machine depends on the greater or lesser difference between 
 the motion forward of the wheel C, and the motion backward 
 of the wheel D; for if these opposite motions were exactly alike, 
 the wheels would indeed all turn, but produce no effect on the 
 arm #, or the axis A. B : whereas this motion is the very thing 
 required. Since then the motion of the bar #, and finger g, 
 depends on the difference of action of the wheels C and D 
 on the intermediate pinion w, we now observe, that in the 
 present state of things, the rims a, b, c, d, have respectively 
 99, 100, 100, and 101 teeth: and that when one revolution has 
 
been given to the wheel C, the rim b of this wheel has acted, 
 by 100 of its teeth, on those of the intermediate pinion w \ in- 
 somuch that if the opposite wheel D had been immoveable, the 
 arm x would have been carried round the common centre a portion 
 equal to 50 teeth, or one half of it's circumference (which effect 
 takes place because the pinion w rolls against the wheels C and 
 D, it's centre progressing only half as fast as it's circumference.) 
 But instead of the wheel D standing still, it has moved in a di- 
 rection opposite to the former, a space equal to -^- of a revo- 
 lution, and brought into the teeth of the pinion w, -^- of 101 
 teeth ; that is, 99 teeth, and 99 hundredths of one tooth : so 
 that the account between the two motions stands thus : 
 The forward motion by the wheel C, is equal to 100,00 teeth 
 And the backward motion by the wheel D, is 99,99 ,, 
 And the difference in favour of the forward motion is 00,01 of i tooth* 
 Or, dividing the whole circumference into 101 parts (each one 
 equal to a tooth of the rim d,J this difference becomes -^- part 
 of -^- 7^0 of a revolution of the axis A B, for each revo- 
 lution of the wheel C. But we have observed, that the arm x 
 progresses only half as much, on account of the rolling motion: 
 whence it appears that the wheel C, must make 20,200 turns to 
 produce one turn of this axis A B. And if, with 20 teeth in the 
 pinion z, we suppose the movement to be given by the handle y, 
 this handle must make more than 20,200 revolutions, in the pro- 
 portion of 99 (the teeth in the wheel) to 20, the teeth in the pinion 
 z. Thusthe said 20,200 turns must be multiplied by the fraction -^ 
 which gives 99,990 turns of the handle, for one of the axis 
 
56 
 
 / 
 
 A B. And finally, if instead of turning this Machine by the 
 handle and pinion y z, we turned it by an endless screw, taking 
 into the rim c, of 100 teeth ; the handle of such screw must 
 revolve 2,020000 times to produce one single revolution of the 
 axis A B ; or to carry the finger g, once round the common 
 centre. 
 
 The above calculations are founded on the very numbers of a 
 Machine of this kind I made in Paris : and of which I handed a 
 model to a public man nearly thirty years ago. I need not add 
 that this kind of movement admits of an almost endless variety : 
 since it depends both on the numbers of the wheels and their 
 differences ; nay, on the differences of their differences. I 
 might have gone to some length in these calculations had I not 
 conceived it more important to bring other objects into view, 
 than to touch at present the extensive discussions this subject 
 invites and will doubtless suggest to many. Suffice it now to say, 
 that here is a simple Machine which gains power (or occasions 
 slowness), in the ratio of two millions and twenty thousand to 
 one ; giving, (if executed in proper dimensions) to a man of 
 ordinary strength, the power of raising, singly, from three to 
 four hundred millions of pounds. It may be useful to observe 
 that using this Machine for an opposite purpose, that of gaining 
 speed, extreme rapidity may be caused by a power acting very 
 slowly on the axis A B. ; only in that case, the difference must 
 be enlarged, and the diameters and numbers of the wheels be 
 calculated on the principles of perfect geering which is as easy 
 in this Machine as in any other. 
 
57 
 OF 
 
 A CRANE, 
 
 Which combines VARIABLE POWERS with speed and safety. 
 
 DOCTOR Gregory (in his Mechanics 2d. volume page 157,) 
 thus introduces the description of this Crane, and the obser- 
 vations with which he tags that description. 
 
 " The several Cranes described in this article, as preferable 
 ' ' to the common walking Crane, while they are free from the 
 " dangers attending that Machine, lose at the same time one of 
 " it's advantages, that is, they do not avail themselves of that 
 ' addition to the moving power which the weight of the men 
 ' employed may furnish : yet this advantage has been long since 
 " insured by the mechanists on the continent: who cause the la - 
 (( bourers to walk upon an inclined plane, turning upon an axis, after 
 " the manner shewn in the figure referred to under the article 
 "foot-mill,-- where we have described a contrivance of that kind, 
 " well known in Germany nearly 150 years ago. The same 
 " principle has been lately brought into notice (probably with- 
 " out knowing it had been adopted before) by Mr. Whyte, 
 " (White) of Chevening in Kent : His Crane is exhibited, fig. 
 " 2 and 4, Plate 10, as it was described in the Transactions of 
 " the Society for the Encouragement of Arts." 
 
 N 
 
58 
 
 C( 
 
 <e 
 
 A, Plate 9, fig. 4, (of this Work) is a circular inclined 
 plane, moving on a pivot under it, and carrying round with 
 <( it the axis E. A person walking on this plane at A, and 
 (f pressing against a lever, throws off a gripe or brake, and 
 " thus permits the plane to move freely, and raise the weight 
 <f G by the coiling of the rope F, round the axis E. To shew 
 " more clearly the construction and action of the lever and 
 " gripe, apian of the plane connected with them, is aCded in 
 *' fig. 5, where B represents the lever, and D the gripe : where it 
 * e is seen that when the lever B is in the situation in which it now 
 <( appears, the brake or gripe D, presses against the periphery 
 *' of the plane ; but when the lever B is driven out to the 
 " dotted line H, the gripe D is detached, and the whole Ma- 
 <( chine left at liberty to move : a rope or cord of a proper 
 " length, being fastened to B, and to one of the uprights in 
 " the frame, to prevent this lever from being pushed too far 
 " towards H, by the man working at the Crane.' 7 
 
 (( The supposed properties of this Crane, (says Dr. Gregory) 
 " for which the premium of forty guineas was adjudged by 
 the society to the Inventor, are as follows : ' ' 
 
 * " 1. It is simple, consisting merely of a wheel and axle : 
 
 ' " 2. It has comparatively little friction, as is obvious from 
 * " the bare inspection of the figures : 
 
 ' " 3. It is durable from the two properties above mentioned : 
 
 * ( ' 4. It is safe : for it cannot move but during the pleasure 
 
59 
 
 * " of the man, and while he is actually pressing on the gripe 
 
 * " lever : 
 
 ' " 5. This Crane admits of an almost infinite variety of differ - 
 ' " ent powers ; and this variation is obtained without the 
 ' '< least alteration of any part of the Machine. If in unload - 
 ' " ing a vessel, there should be found goods of every weight, 
 ' " from a few hundreds to a ton and upwards, the workman 
 ' "will be able so to adapt his strength to each, as to raise it 
 ' " in a space of time, (inversely) proportionate to it's weight, 
 ' " he walking always with the same velocity as nature and 
 ' " his greatest ease may teach him." 
 
 " ' It is a great disadvantage in some Cranes, that they take as 
 " ' long a time to raise the smallest weight as the largest ; unless 
 *' ' the man who works them turn or walk with such velocity as 
 " 'must soon tire him. In other Cranes, perhaps, two or three 
 " 'powers may be procured; to obtain which, some pinion 
 " ' must be shifted, or fresh handle applied or resorted to. In 
 " ' this Crane on the contrary, if the labourer find his load so 
 " ' heavy as to permit him to ascend the wheel without turning 
 " 'it, let him only move a step or two towards the circum- 
 " ' ference, and he will be fully equal to the task. Again, if 
 " 'the load be so light as scarcely to resist the action of his 
 " t feet, and thus to oblige him to run through so much space 
 f( 'as to tire him beyond necessity, let him move laterally to- 
 " 'wards the centre, and he will soon feel the place where his 
 f( ' strength will suffer the least fatigue by raising the load 
 
60 
 
 " ' in question. One man's weight applied to the extremity of 
 " ( the wheel would raise upwards of a ton : and it need not be 
 " ' added that a single sheaved block (at the jib) would double 
 *' ' that power. Suffice it to say that the size of the machine 
 " ' may be varied in any required degree, and that this wheel 
 " ( will give as great advantage at any point of its plane as a 
 ' common walking wheel of equal diameter ; as the inclination 
 6 can be varied at pleasure, as far as expediency mayj re- 
 quire. It may be well to observe that what in this figure is 
 ' the frame and seems to form a part of the Crane, must be 
 considered as part of the house in which it is placed ; since it 
 " ' would be mostly unnecessary should such cranes be erected 
 *' 'in houses already built : and with respect to the horizontal 
 " 'part, by walking on which, the man who attends the jib, 
 " occasionally assists in raising the load, it is not an essential 
 s< ' part of this invention, when the crane and jib are not con- 
 " ' tiguous : although, when they are, it would certainly be 
 " ' convenient and economical." 
 
 The Doctor continues: "Notwithstanding, however, the advan- 
 " tages which. have been enumerated, Mr. Whyte's (White's) 
 " Crane is subject to the theoretical objection, that it derives 
 " less use than might be wished from the weight of the man or 
 " men : for a great part of that weight (half of it if the incli- 
 " nation be 30 degrees,) lies directly upon the plane, and has 
 " no tendency to produce motion. Besides, when this Crane is 
 "of small dimensions, the effective power of the men is very 
 
" unequal ; and the barrel too small for winding a thick rope : 
 " when large, the weight of the materials, added to that of 
 " the men, put it out of shape and give it the appearance of an 
 "unweildy moving floor." 
 
 The Doctor continues : ' ( We know one large Crane of 
 " this construction, which has an upright post near the rim on 
 " each side, to support it, and keep it in shape ; and as 
 <c much as possible to prevent friction, each post had a ver- 
 " tical wheel at it's top." (N. B. / never saw, or heard, 
 " before, of this monster.) " We were informed this Crane 
 was seldom used; and that it was soon put out of order. Nor, 
 moreover, is it every situation that will allow the Crane - 
 rope to form a right angle with the barrel On which it 
 " winds; and when this angle is oblique, the friction must 
 "be much increased. The friction arising from the wheels 
 ' ' at the top of the vertical crutches might indeed be got shut 
 of, by making the inclined wheel very strong ; but this 
 would add greatly to the friction of the lower gudgeon of 
 the oblique shaft, and considerably increase the expence of 
 " the Machine." 
 
 "There remains then (says Dr. Gregory) another stage of 
 " improvement with regard to the construction of Cranes, in 
 "which the weight of the labourers shall operate without di- 
 " minution, at the end of an horizontal lever ; and in which 
 " the impulsive force thus arising, may be occasionally aug- 
 
 o 
 
62 
 
 mented by the action of the hands, either in pulling or 
 lifting and then follows the conclusion." " This step in 
 the progress has been lately effected by Mr. David Hardie, 
 of the East India Company's Bengal warehouse!" 
 
 I cannot follow the author (whoever he be) of the glowing 
 picture next given of Mr. Hardie 's Invention, (to which 
 the obloquy thrown on my poor abortion is clearly the foil) as 
 my readers must already be gasping to "get shut" of such 
 unmitigated Bathos, bestowed on so trivial a theme. With 
 respect to my Crane, I shall only say that it fulfilled the condi- 
 tions required by the Society, and obtained the Premium : and 
 if on the one hand, the language in which, thirty years ago, I 
 described it, exhibits the impetuosity of youth, untempered with 
 the moderation of age, I will say on the other, that if impartial 
 criticism, mechanical acumen, or comprehensive science are es- 
 sential components of a mechanical work of high pretensions,, 
 these qualities were seldom more wantonly abandoned or abused, 
 than in the paragraphs above quoted : except, perhaps, in the 
 attack of the same work, on the labours and character of the 
 justly celebrated Watt, whose merits had this author known 
 how to appreciate, he could not thus have attempted to lessen 
 in the public esteem. 
 
 But to return, this Diatribe begins by comparing my Crane 
 to a foot mill : and kindly supposes I did not know that its 
 principle existed in Germany 150 years ago. But the fact is, 
 
63 
 
 my object was nothing like that of the author of the mill in 
 question : the very figure of which, proves that he had no 
 view to the variation of power by change of place on the wheel : 
 whereas that is the principal use I make of this "unwieldy 
 moving floor," as the Doctor heavily terms it. Again, this 
 author asserts that by making men walk on an inclined plane, 
 I derive less use than might be wishd from their weight ; and 
 yet! a page before he told us that " the mechanists on the Con- 
 tinent had long since insured the advantage of availing them- 
 selves of that addition to the moving power which the weight 
 of the men may furnish ;" so that poor / have the merit of 
 imitating them without knowing it, and yet of not drawing the 
 same advantages as they from the self same principle ! 
 
 But again, " a great part of the weight of the man (half of 
 "it, if the inclination be 30 degrees) lies directly on the 
 "plane, and has no tendency to produce motion," which one 
 sided truism is placed there to give relief to the portentous 
 dictum, which follows: that "there remains then another 
 " stage of improvement with regard to the construction of 
 " Cranes, in which the weight of the labourers shall operate 
 " without diminution at the end of an horizontal lever : and 
 " that stage has been effected by Mr. D. H. of the East India 
 " Company's Bengal warehouse." 
 
 But is this conclusion difinitive ? are there no countervail ins 
 
 o 
 
 evils? Will Dr, Gregory presume to say there is no disid- 
 
(54 
 
 vantage attending this advantage ? Did the Doctor ever 
 ascend an upright ladders ? and did he prefer that, to going up 
 an easy flight of stairs ? was he ever in the geometrical stairs 
 of St. Paul's? or in any large winding stair -case ? and if so did 
 he prefer ascending close to the nucleus ? or did he quickly 
 seek a point where the step was wider than high ? most cer- 
 tainly the latter ; and why then did he not perceive that if 
 the weight of my man is diminished one half on the plane, 
 for the very same reason, a given elevation of his feet (on 
 which his fatigue depends) will cause a circular motion twice 
 as extensive ; yet this is quite as clear as the Doctor's ex- 
 parte proposition. 
 
 But I must wade on a little further, trusting that my readers 
 will exert a little more patience to follow me : for this same 
 dictum of the Doctor's accuses indirectly, the Society of Arts 
 of being a set of blockheads, for remunerating an Invention with 
 only supposed properties. I really wish these self-constituted 
 judges of other people's labours would utter their oracles with 
 more regard to truth and propriety ! and above all , not mix up 
 their passions (which alas ! are not always purified by science) 
 with their judgement on the merits of other men's inventions. 
 Had the author of this article been wise enough to proceed thus, 
 he would not have supposed me capable of offering suppositions for 
 realities; nor the Society of Arts of rewarding as genuine, sup- 
 positions merit ; and still less would he have emblazoned the very 
 properties he calls supposed, with reality written in glaring cha- 
 
65 
 
 racters on every one of them ! These properties are in fact only 
 the transcript of what the society required of the candidates: 
 and I therefore said my Crane is simple : Can this author say it 
 is not ? I said it has little friction ? will he say it has much ? 
 I said it is durable : Is it now possible to contradict this ? I 
 said it is safe : and will Dr. G. say it is not, when it is move- 
 able, only during the wish of the workman : since whatever 
 suspends this wish, (whether accident or design) the Crane 
 becomes of itself immoveable. In fine, I observed, that this 
 Crane admits of an indefinite number of powers, without any 
 modification of it's parts ; and can any one say these are sup- 
 posed properties ? If the Doctor or his coadjutors persist in 
 saying so, I must suppose them actuated by improper motives ; 
 for truth will never bear them out in these allegations. I take 
 leave to add, that but for the interests of truth, these strictures 
 had never appeared. Even self-defence would not have pro- 
 voked one line of them : But I felt it incumbent on me to deter, 
 if possible, inadvertency as well as malevolence, from infesting 
 with the thorns of misrepresentation, the paths which genius 
 explores, in search of useful knowledge. 
 
66 
 OF 
 
 A DIRECT AND DIFFERENTIAL PRESS, 
 
 TVith two Powers : of which ONE immense. 
 
 .1 HE effects intended to be obtained from this Press, are to 
 introduce two distinct powers ; the one to raise and lower the 
 pressing cap with convenient speed ; the other to press with 
 very great force. In Plate 10, A B is a frame, the under part 
 of which contains the goods to be pressed. The toothed wheel 
 C D turns the screw S, and that E F turns the nut G H, both 
 the same way. The long pinions I K, turn both these wheels 
 C D, and E F; and occasionaly one only, as will be seen pre- 
 sently. L M are two bevil wheels on the axes of the long pin- 
 ions IK; and N O, are two similar ones, on the power 
 shaft P Q. This latter shaft runs in two boxes R T, the stems 
 of which fit and turn in the gudgeons of the long pinions, or 
 rather suffer these to revolve round them : being pinned on 
 through a circular groove which connects them in the perpen- 
 dicular direction only. Finally, the rope and pulleys indicated 
 at X Y Z, serve to raise both shaft and pinions ; thus disen- 
 gaging the latter from the wheel E F, when the nut G H, 
 is not to be turned. We may remark, that the parts M T O 
 are doubled in this machinery, at L R N ; merely to take 
 away the side tendency from the screw S : as otherwise 
 
one half of this mechanism would produce the very same 
 effect, and leave the Machine the more simple. Supposing 
 now, this Press charged with goods in it's present position, 
 
 The wheel C D, having 69 teeth ;1 with proportionate 
 that E F, ,, 70 diameters. 
 
 The pinions I & K, each 10 ,, 
 
 The wheels G N & M O equal ; 
 
 The thread of the screw S, 1 inch ; and in fine, the crank 
 V Q, having a radius of 18 inches. 
 
 In this state of things, the motion of the pressing cap W, is 
 to the motion of the handle V, as 1 to 52164; and, the power 
 gained bears the same proportion to the strength exerted : for 
 when the handle has made one revolution, the wheel C D 
 
 
 has made ^ of a revolution, and the screw would have gone 
 down eg of a thread, or ^ of an inch : hut in the same time 
 the wheel E F has turned the nut ^ of a revolution in the 
 same direction ; so that the latter has only gone down ~ 9 less 
 ~ of an inch ; that is, (reducing to a common denominator) 
 
 4830 ~ 483b = 483o ~ 483 f an ^ nc ^ : Now to do this, the handle 
 Q V has described a circle of three feet in diameter, or in round 
 numbers 9 feet, or 108 inches ; and to complete a descent of 
 the screw of one thread, (or one inch) the handle must move 
 through a space 483 times as great ; that is, a space of 
 108 inches multiplied by 483 = 52164 inches : whence we see 
 that the power gained is, as 52164 to 1 : and reckoning a 
 man's strength at ISOlbs. (exclusive of friction) that strength 
 
68 
 
 exhibits a pressure of Jive millions two hundred and sixteen 
 thousand four hundred pounds ; or upwards of two thousand two 
 hundred tons: a result not unworthy to be mentioned with those 
 of the hydraulic press ; to which it might be still further assimi- 
 lated by other proportions in the screw and nut wheels CD, E F. 
 Adverting now, to the second property of this Machine : namely 
 the simple power intended to act when the press is to be laden 
 or discharged, the handle V should first be turned backward, 
 until the cap W has slackened upon the goods ; and the long 
 pinions I K be raised by the mechanism X Y Z, which pinions, 
 then geering only in the wheel C D, will raise the cap 1 inch for 
 
 fiQ 
 
 every turn of that wheel ; or for every -^ turns of the handle V, 
 say in round numbers for every seven turns : here then is a 
 power of 7^6 to 1 ; very different from the former; yet pro- 
 duced by only a few inches motion of the long pinions I K. 
 
 We remark further, that the figure shews at G H two of a 
 system of friction rollers, destined to lessen the resistance which 
 the turning -nut would otherwise oppose to the motion of the 
 Machine. As to the friction between the screw itself and the 
 nut see a future article, in this part, tending to lessen or take 
 away the friction of screws in general. 
 
69 
 OF 
 
 A PERISTALTIC MACHINE, 
 
 For raising much Water to small heights. 
 
 i HYSICIANS will soonest understand the nature of this 
 Machine, from the name I have given it. It is perhaps the 
 most simple of Water -Machines ; and certainly not the least 
 efficient where it applies. It's name is taken from the simi- 
 larity of its action to the creeping of a worm, and to some 
 of the functions of animal life. Yet it might be explained 
 to the most unlettered housewife, when in the act of con- 
 verting certain long vessels into chitterlings; or making 
 room for the materials of a sausage or hlack pudding. To be 
 serious: this Machine, in it's simplest form, (see Plate 11) 
 consists of a flexible tube C D, fig. 2, nailed to the ground, 
 and connected with a short tube of metal containing two 
 valves, A B, itself affixed to a box D, filled with water, or 
 into which water flows. This water runs through the valve 
 A, and distends the tube C D, on which rolls the body F, 
 similar in form to a land roller. The Machine acts in the fol- 
 lowing manner : When the roller is drawn to the end D of 
 the tube, the water fills the latter through the valve A ; and 
 on the roller's return, this water is forced into the rising tube 
 through the valve B. 
 
70 
 
 The above is the simplest form of this mechanical trifle : 
 But it has the disadvantage of an inconstant vibratory motion, 
 not only of the water but the roller : which latter being 
 heavy, would absorb considerable power. To remedy this evil, 
 I have given the principle a rotatory form in fig. 1 ; where A 
 B C is a spiral tube, duly fastened to the bottom of a shallow 
 tub D E. At B is seen a conical roller, having the middle 
 of the bottom of the tub for its summit and centre of gyra- 
 tion. The tube ABC, occupies rather more than one circum- 
 ference ; so that the cone presses during a small part of it's re- 
 volution on both spires at once : by which means the Machine 
 would act without even one valve; though it is better fo place 
 one, under the opening A. Now, observe the operation : as 
 the cone rolls over the tube and round the common centre, in the 
 direction of the arrow R the water enters behind it, through the 
 opening A, (for the tub is plunged a few inches into the water) 
 and is forced by it's pressure into the ascending tube, which 
 is a continuation of that, ABC. It would be superfluous to 
 add, that these tubes are shewn in the figures as cut open, and 
 presenting their inside to view ; which representation is adopted 
 in order to shew more completely the valves A and B of the 
 2d. figure. 
 
 An objection may occur to some, at sight of this Machine : 
 namely, that the roller or cone B, would soon destroy the 
 flexible tubes, by pressing too hard on their puckered texture. 
 But to obviate this difficulty I have added, in fig 3, a form of 
 
71 
 
 the tube (supposed of leather) which insures a proper position 
 of the leather under these rollers ; accompanied by ledges A B, 
 on which their surplus weight would bear, so as to annul 
 every excess of pressure on the tube. 
 
 In many of the subjects I shall have to lay before my readers, 
 the forms are so numerous as to leave some difficulty in judg- 
 ing where the actual descriptions ought to end. This article 
 itself, small as it is, offers an example of this : for I could draw 
 several corollaries from the foregoing, that would offer new 
 degrees of interest : but I am withheld by the apprehended 
 want of room in the plates. I must at least defer my first in- 
 tention, of multiplying examples and shewing the influence of 
 FORM on mechanical results in general. It will, however, 
 always be open to me, to resume this subject when the principal 
 object has been achieved that of making known the principles 
 of these inventions, with their most useful forms and properties. 
 I observe, however, what has just occurred to me, that this 
 Machine would be somewhat more durable, if the water-tube 
 was pressed between two rollers, instead of being contracted 
 from one side, by the action of a single one. 
 
72 
 OF 
 
 A DRAYMAN'S CANTER, 
 
 Or inclined Plane with increased Power. 
 
 THIS Machine presents a simple method of increasing the power 
 of the inclined plane, as used by carters or draymen for loading 
 their carts ; and called by them (in some counties) CANTERS. 
 It admits of a gentle declivity in those planes : and thus consi- 
 derably increases their power. The means consist in the trans- 
 fer of the declivity from one end of the Machine to the other. 
 Thus (plate 11, fig 4) when the cask is rolled up from A to 
 B, it is wedged in that position by the wedge F ; when so 
 much of its weight is supported by the feet C, (for all the feet 
 are in pairs) that the end D of the Canter can be raised with 
 ease to E, so as to re-form the plane, in the direction of C E ; 
 at which time the feet D G drop into an upright position, and 
 secure this new state of the plane. The cask is now rolled 
 back from B to E, where it is found twice as high as it was 
 at B; and this manoeuvre may be repeated several times ac- 
 cording to the number of feet provided, and their length res- 
 pectively. The power of an inclined plane, is as its length to its 
 height : and that power is doubled when the force is applied 
 at the circumference of a cask or other rolling body. So that, 
 here, the power being as 16 to 1, if a man can exert an energy 
 of 200/A. the cask may weigh 3200/. and still be raised with 
 
73 
 
 ease on this Canter, which therefore is three times as powerful 
 as though the weight was raised directly from A to F in the 
 usual method. 
 
 Should it be suggested, or thought, that this Machine ap- 
 plies only to rolling bodies, I would just say that it might apply, 
 cseteris paribus, as wellto bodies sliding uptheplane; or (using 
 a small truck on the Machine) it might serve in a cotton 
 warehouse, for piling the bags, &c. This System is doubtless 
 susceptible of discussion, and may require to be modified for 
 different purposes : but it is by no means devoid of practical 
 capabilities. 
 
74 
 OF 
 
 A PERPETUAL WEDGE MACHINE, 
 
 Being a simple Method of gaining Power. 
 
 .IN Plate 12, fig. 5, let A B represent a wheel and axle, of 
 which the wheel A is divided into 100 teeth ; (more or less) 
 and let C represent a second wheel with one tooth (or several) 
 less than those of the first wheel A. These two wheels are 
 concentric, for the axis of the wheel A, turns in the hollow 
 centre of the wheel C ; which latter wheel is fixed to the frame 
 of the Machine, not here represented. D is a pinion that 
 circulates round the wheel A andC in and along with the frame E 
 as impelled by the hand acting on the handle F. Thus the 
 circulating pinion is constantly occupied by means of its wedge 
 formed teeth (of which one is shewn at D), in bringing the 
 unequal teeth a b of the wheels A and C abreast of each other : 
 whence arises a slow revolution of the wheel A, and of the 
 axis B round the common centre. For if the number of the 
 teeth on these wheels (A and C) differ only by unity or one, 
 then must the handle D revolve one turn about that common 
 centre to occasion ^ part of a revolution of the wheel A, 
 and of course 100 turns to move the axis B once round that 
 centre. And if further the wheel A be three times the diameter 
 of the axis B, the power gained there would be as 300 to 1, 
 
that is a power of \lb. at a distance from the centre, only 
 equal to the radius of the wheel A, would countervail a weight 
 of SOOlb. suspended on the axis B : and supposing a man's 
 strength to he SOOlb. he would raise (exclusive of friction) 
 30000 Ib. by this simple machine. 
 
 To shew more fully the essential properties of this Machine, 
 I have represented only three teeth in all : one b in the fixed 
 wheel C ; one a little smaller a, in the wheel A, (since this 
 wheel has more teeth than the former) and one D in the cir- 
 culating pinion, whose form and manner of acting justifies 
 in my apprehension, the name I have given to the Machine 
 a perpetual wedge Machine. I shall only add that there would 
 equally be motion if the teeth of the wheel A instead of being 
 more numerous than those of the wheel C were less numerous : 
 but the manner of action would be different and I think less 
 perfect. 
 
 This Machine is among the first inventions I carried into real 
 practice on coming to manhood. It must be about 40 years ago, 
 and was first constructed as a Crane at the request of the late 
 Doctor Bliss, of Paddington. It may offer some difficulty as a 
 Power Engine from the small diameters and the friction thence 
 resulting : but for any Machine where great slowness is desirable, 
 whether to express slow motion, or to count high numbers, &c., 
 it still appears to me a very good Machine. 
 
76 
 OF 
 
 A DROPPING- WEIGHT-MOVER; 
 
 Or Machine for lengthening the Time of going of a Clock, 
 Jack, or other J freight- Machine. 
 
 SUPPOSE A B (plate 12, fig. 4) to be the first wheel of a 
 Clock or other Machine required to go a long time without 
 winding up. This wheel works into the two pinions c d, hoth 
 of which are connected hy ratchets with the axis E F of the 
 wheel G H, in one direction only ; insomuch that "whether 
 the wheel A B turn forward or backward, the wheel G H will 
 always turn the same way. This process is well known in the 
 mechanical world ; and I have merely adapted it to my present 
 invention. F and G are two tubes, or square vessels, of equal 
 size, containing a number of balls the tubes so balanced 
 against each other, that one of them is always heaviest by the 
 weight of half a ball. Suppose for example that the tube F 
 contains six balls and the tube G five ; and that the tube G 
 is so much heavier than F as only to be outweighed by half 
 a ball : That half will then be the moving power ; and the 
 vessel F will turn the wheel A B backward, raising the tube 
 G at the same time. But arriving at the bottom the mechanism 
 m will let go the lowest ball in F, and then the tube G which 
 is at the top will preponderate and turn the clock till it also 
 
77 
 
 gets to the bottom; when a similar mechanism at"n, will dis- 
 engage one ball from it, by which subtraction the tube F will 
 resume the ascendency and perpetuate the motion. Thus may 
 the going of any clock, jack, &c. be protracted to a period 
 almost indefinite. Nor need it, strictly speaking, be wound up 
 at all. It is only taking care to drop at proper intervals, an 
 equal number of balls into each tube, and this reciprocation 
 of movement will become perpetual. The figure of this little 
 Machine is unfortunately small : and the scapement is but im- 
 perfectly shewn ; It has however, only one property that it is 
 essential to notice ; which is that the detent o, shall suffer the 
 cross m to turn only one quarter round at each discharge : and 
 this is insured by the spiral ledge of the four ratchet teeth m, 
 which by a pin fixed to the side of the detent, draw the latter 
 down into the succeeding tooth as soon as the tube F begins 
 to rise, so that there is only one ball discharged at each de- 
 scent of that tube. 
 
78 
 OF 
 
 A MACHINE, 
 
 To promote Evaporation, with or without Heat. 
 
 J. HE vessel containing the liquid to be evaporated, (see Plate 
 12, fig. 6,) is long and shallow, and the liquid rises nearly to 
 it's brim. In this vessel is placed a long hollow drum A B, 
 covered with open wire- work, or any kind of cloth of a very 
 loose texture. This drum turns slowly, on the hollow centre 
 C, to which is fitted a stuffing box and tube, connecting 
 the drum A B, with the pump P ; the latter worked by any 
 convenient power. The pump then, drives air, either hot or 
 cold into the drum, and thence through the interstices of it's 
 texture; where it comes in contact with the liquid at an indefi- 
 nite number of points, breaks the films formed by the liquid, 
 and, saturated thereby, passes into the open air; thus occasion- 
 ing a rapid evaporation, which might be increased either by 
 heating the liquid or the injected air, or both, ad libitum. 
 The whole idea consists in the multitude of points of contact 
 between the liquid and the drying medium. 
 
A CUTTING OR GRATING MACHINE 
 
 For Green Roots, Tobacco, fyc. 
 
 i HIS Machine is composed of a perpendicular axis A B, 
 fig: 7? driven with considerable velocity by any proper geering. 
 C D is a vessel formed something like a shoe with the toe cut 
 off : its entrance D is concentric with the shaft A B, and a 
 weight m, fastened to it's side, equilibrizes the weight of the 
 eccentric part C. Around this vessel, and concentrically with 
 it, is placed a cylindrical rasp or grater E F, consisting, here, 
 of a number of blades so grooved on one surface as that by 
 grinding them obliquely on the edge, each one shall form a line 
 of sharp teeth, which, combined with those of the other blades, 
 constitute a rasp similar to that used for powdering dye-woods ; 
 with this difference however, that these blades have interstices 
 between them, through which the pulp escapes outwards, and thus 
 the rasp is kept clean at all times. When this Machine is used 
 the roots are merely thrown into the vessel D as into the hop- 
 per of a mill, and they are pressed against the rasp by their 
 own centrifugal force ; which is made as strong or weak as de- 
 sired, by the greater or less velocity of the Machine. 
 
 _ 
 
 This Machine owes its origin to the decree of the French 
 
80 
 
 Emperor, for encouraging the making of sugar from beet -root. 
 With the other mechanicians of Paris I was called upon, by a 
 house engaged in that trade, to try my hand upon it ; and this 
 Machine was the result. It acts fast and well ; and from being 
 less liable to clog, than most of the others, is I believe superior; 
 though this was never proved by any comparative experiment. 
 If it were desired to cut any substance with this machine, 
 the blades would be sharp knives, instead of being toothed ; 
 and they would be placed obliquely to the circumference : but 
 the process of grating is that for which it was exclusively 
 designed. 
 
81 
 OF 
 
 A SCREW, 
 
 With greatly diminished Friction. 
 
 JjlY readers will perceive, that I have altered the title 
 given in the prospectus to this Invention. It has been done 
 in deference to the opinions of some persons in high reputa- 
 tion in the mechanical world, who hold that there can be no 
 motion whatever without friction. For my own part I am no 
 believer in several sorts of friction : and must therefore, re- 
 quire a new definition of friction, before I can flow with the 
 stream. As the question, however, is not yet before my 
 readers, I shall wave the discussion at present, and describe 
 this invention, as introducing the rolling motion into the 
 threads of a screw ; thus taking away the GREATEST PART of 
 the friction on every supposition. 
 
 In Plate 12, fig. 8, A is the screw, and B C the nut, bored 
 large enough to receive the screw, bodily, without any pene* 
 tration of their threads. Nevertheless, these threads are made 
 to occupy the same length, in both screw and nut, as though 
 they did enter each other : so that the two parts running 
 parallel to each other, leave a square interstice b, all along both 
 nut and screw : into which balls of brass, or soft iron are 
 
 T 
 
82 
 
 introduced, which at once restore the screw -property with- 
 out it's friction : a friction so considerable in the common 
 screw, that it always surpasses the effective power, since it 
 remains closed, (in a vice for example) while holding any 
 object squeezed with all the force a man can apply. I have 
 mentioned the use of soft balls : it is in order that they may 
 all act together, and work themselves to a common bearing. 
 It will appear by fig. 9, that the acting balls might, or per- 
 haps ought to be, separated from each other by a set of smaller 
 ones ; since in this case, the surface of the touching balls 
 move the same way, avoiding all friction between them ; 
 and leaving the friction only between those surfaces that are 
 exempt from heavy pressure. These circumstances will be 
 understood by consulting the direction of the arrows in fig. 9 ; 
 arid I have added two other sketches, to shew the principle in 
 it's application to square threaded screws, &s at fig. 9 ; or to 
 oblong threaded screws, whose threads penetrate each other, 
 in fig. 12. I have further, in fig. 8, sketched one of the 
 methods I propose for supporting the weight of the descending 
 balls, and returning them again into the nut. Considering 
 the balls as a fluid, I have provided a rising column of them, 
 which the working of the screw downward will fill : and the 
 weight of the balls themselves will return them into the nut, 
 when the screw is drawn upward. 
 
OF 
 
 MICROMETER. 
 
 A HIS interesting Machine, see Plate 12, fig. 11, consists of 
 a screw divided into three parts, , Z>, c; the first, , is a 
 mere cylinder to centre the screw at that end : c is a screw of 
 (suppose) 20 threads to the inch ; and b another screw of 
 21 to the inch. D E represents the frame of the Machine) 
 the part E being the fixed nut of the screw C, while the 
 piece f g, forms the moveable nut of the screw C, carrying 
 a finger g, along the graduated bar, E g D. If now, the 
 screw be turned once round by the button H, it will have 
 moved to the left ^ of an inch ; while the nut and it's finger g 
 will have progressed on it's screw ^ an of inch to the right : 
 and the difference ^ ^ = 4 of an inch is what the nut f 
 has really moved to the left, along the bar E g D. If there- 
 fore, the rim of the button be divided into 100 parts, one of 
 these will represent ^555 P ar * of an inch by this Micrometer : 
 and I need not add, that this minute portion may be rendered 
 still more minute at pleasure. The means of doing this are 
 evident : It is only making the screws b and c nearer alike in 
 fineness, or number of threads per inch ; as 29 and 30, 30 
 and 31, &c. 
 
I hope it will be understood, that I do not give any of these 
 Machines as the only examples I could furnish of the ap- 
 plication of the principles on which they are founded. This 
 very Machine is not a Micrometer only ; it might be (if made 
 in proper forms and dimensions) a vice, a press, or other power 
 Machine. It has been already hinted, that change of form must 
 remain to be considered hereafter. 
 
 I have chosen to bring forward this Machine at an early 
 stage of the work, because it has, inadvertently perhaps, been 
 ascribed to another person. I refer to an article in the 
 celebrated programme of M. Hachette, of Paris ; with which 
 is combined an essay on the composition of Machines, by 
 Messrs. Lanz and Betancourt. In the article D 3, at page 10 
 of that work, are the following words : 
 
 (< 
 " 
 
 M. de Prony a trouve une maniere de transformer le 
 mouvement circulaire, en un autre rectiligne dont la vitesse 
 " soit aussi petite que Ton voudra;" and further on Pidee 
 " en est extremement simple, heureuse; elle est d'ailleurs sus- 
 " ceptible de plusieurs applications utiles aux arts." And in 
 page 11, are these words " C'est ainsi que M. de Prony 
 " est parvenu a une solution aussi simple qu'ingenieuse du 
 " probleme qu'il s'etoit propose." 
 
 For the sake of my English readers, I subjoin a translation 
 of these passages : " Mr. de Prony has found (or invented) a 
 
85 
 
 "manner of transforming a circular movement into a rectilinear 
 " one, of which the velocity shall be as small as may be de- 
 " sired." and further on " This idea is extremely simple and 
 " happy : and is besides, susceptible of several useful applica- 
 tions to the arts/' And in page 11, are these words 
 ' ' Thus has Mr. de Prony given a solution as simple as it is 
 ingenious, of the problem which he had proposed to himself/' 
 
 The above account appears in 1808, and M de Prony does not 
 prevent or disavow it. Perhaps he had forgotten the circum- 
 stance : and perhaps he did not know of this publication : but 
 I solemnly declare that I shewed HIM this Micrometer, ex- 
 ecuted, fourteen years before ! that is, while he and M. 
 Molard were making their report on the Machines proposed 
 for the Water-works at Marly. I certainly wish to accuse 
 no body in this affair : but if I did not state the fact as it is, 
 I should, myself, be stigmatized as a plagiary ! I am forced, 
 therefore, to take my stand on the adage " Fiat justitia mat 
 coelum/' 
 
 In closing the first Part of this Work, I cannot but express 
 my gratitude for the unexpected degree of support, with which 
 my numerous Subscribers have honoured me. I presume to offer 
 these pages as a fair Specimen of w T hat they may expect in 
 the four succeeding Parts, namely, as it regards the ex- 
 ecution : for the materials of what remains, include objects of 
 greater importance than those preceding. If I have been for- 
 
 u 
 
86 
 
 tunate enough to raise any favourable expectations in the minds 
 of my present readers, I hope they will express those feelings ; 
 and thus induce others to join in bringing to a useful close, a 
 work which is at least intended to produce unmixed public 
 utility. From criticism, I expect candour : and should my 
 intentions, though pure, be misrepresented should envious 
 tongues or pens assail my labours, or asperse my character, 
 I will defend both, after I can use my Book as my shield 
 that is, after I have fulfilled my Engagements with my Sub- 
 scribers : of whom (in expectation of meeting them again 
 within three months) I now respectfully take leave. 
 
 J. W. 
 
 Wo. 5, Bedford-street, 
 Chorlton Row. 
 
SYNOPSIS, 
 
 (IN ALPHABETICAL ORDER) 
 
 OF THE 
 
 CENTURY OF INVENTIONS 
 
 COMPOSING THIS WORK. 
 
 Note. The objects with Numbers after them are those contained in the present PART : and the 
 Numbers shew the Pages where they stand. 
 
 1 Adding Machine ; or Machine to 
 cast up correctly large columns 
 of figures. 
 
 2 Air Pump ; essay towards com- 
 pleting the vacuum. 
 
 B 
 
 3 Barrel Spring, to lengthen the 
 going of Clocks and other spring- 
 driven Machines. 26 
 
 4 Boats (serpentine) for lessening 
 the expence of traction. 
 
 5 Bobbin or Lace (Machine for 
 making) and for covering Whips, 
 &c. with great rapidity. 
 
 6 Bowking Machine for Calico 
 Printers. 
 
 7 Bucket Wheels (a combination 
 of) to raise water. 
 
 8 Canals (open) as Hydraulic Ma- 
 chines of great force. 
 
 9 Canter, or inclined Plane for 
 Draymen. 72 
 
 10 Chain to act equably on my 
 wheels. 
 
 1 1 Chocolate Mill (rotatory) 
 
 12 Cocks (equilibrium} to avoid leak- 
 age. 
 
 13 Colour Mill for Calico Printers. 
 
 14 Compasses (bisecting) 
 
 15 Cotton -(Machine for batting.) 
 
 16 Crane, combining variable pow- 
 ers with speed and safety, (re- 
 warded by the Society of Arts) 57 
 
 17 Crank (epicvcloidal 1 ! or parallel 
 motion. Rewarded by BONA- 
 PARTE. 30 
 
 D 
 
 48 Dash Wheel for Calico Printers, 
 acting with greater rapidity than 
 .usual. 
 
 19 Differential Wheels for gaining 
 immense power. 54 
 
 20 Doffing Machine, of great force 
 for taking Cylinders from their 
 Mandrills. 
 
 21 Draw-bench for my twisted pi- 
 nions. 
 
 22 Dynamometer, for measuring 
 powers and resistances in motion. 
 15 
 
 23 Dynamometer, second kind. 
 
 E 
 
 24 Engine for cutting my Patent 
 Wheels in small and middling di- 
 mensions. 
 
 25 Engine for cutting my large bevil 
 Wheels and wooden Models, ei- 
 ther on my System, or the usual 
 one. 
 
 N. B. These objects will occupy 
 considerable space in the work . 
 
 26 Engraving Machine for Calico 
 Printers, being an important ap- 
 plication of my Cog or toothed 
 Wheels. 
 
 27 Engraving Machine for large pat- 
 terns. 
 
 28 Essay to derive power from ex- 
 panding Solids. 
 
 29 Evaporation (Machine to pro- 
 mote. 78 
 
 30 Eyes ( Machine for making rapidly ) 
 
 F 
 
 31 Fire escape (on a retarding prin- 
 ciple.) 
 
 32 (by breaking the fall.) 
 
 33 Fires (Portable Engine to extin- 
 guish.) 
 
 34 Fires (Watch Engine always 
 ready for.) 
 
 35 Flax (Machine for breaking) with 
 rapidity. 
 
 36 Forging Bar iron and steel (Ma- 
 chine lor) 
 
SYNOPSIS* 
 
 37 Friction (to prevent) 
 
 38 Friction (to prevent) Thoughts on 
 
 G [for) 
 
 39 Geering and ungeering (Machine 
 
 40 Do. Do. for swift motions. 
 
 41 Grating or cutting green Roots, 
 Tobacco, &c. (Machine for.) 73 
 
 H 
 
 42 Helico-Centrifugal Machine, for 
 raising water in large quantities. 
 
 43 Horse Wheel for saving room and 
 gaining speed. 53 
 
 44 Horse Wheel (reciprocating) for 
 Mangles, &c. 
 
 45 Horse Wheel, with means for 
 turning the Horse when he acts 
 in two directions. 
 
 46 Horizontal Pump of large pro- 
 duce, driven by wind. 
 
 47 Hot Air as power, while heating 
 liquids, rooms, &c. 
 
 L 
 
 48 Lamp for the Table ; suspending 
 the oil by it's weight. 
 
 49 Lithographic, or Copper-plate 
 Press, with several curious and 
 useful properties. 
 
 M 
 
 50 Machine for clearing turbid li- 
 quors. 
 
 51 Machine for driving Boats on 
 Canals, under Tunnels, &c. with- 
 out disturbing the Water. 
 
 52 Machine to assist in taking Me- 
 dicine, Pills, &c. (Humani ni- 
 hil alienum) 
 
 53 Mangle (perpetual or rotatory). 
 
 54 Marine-Level (two essays on a) 
 
 55 Microjneter for measuring very 
 minute spaces. 83 
 
 56 Mirrors to collect Solar Heat, 
 
 (method of forming) 
 
 57 Mover, by dropping weights. 76 
 
 N 
 
 58 Nails (Machine for moulding.) 
 
 59 Nails (Machine for forging.) 
 
 P 
 
 60 Pencyclograph, or Instrument for 
 describing porti ns of Circles, and 
 finding their centres by inspec- 
 tion. 51 
 
 61 Peristaltic Machine, for raising 
 much water, to small heights. 69 
 
 62 Persian Wheel modified, for rais- 
 ing water. 
 
 63 Pitch-fork, for musicians, with 
 variable tones. 
 
 64 Power-wheel by heated Air. 43 
 
 65 Press, direct and differential. 66 
 
 66 Press (eccentric Bar.) 
 
 67 Printing Machine (two coloured.) 
 
 68 Protracting Motion (Machine 
 for) 49 
 
 69 Pullies (my Patent much im- 
 proved.) 33 
 
 70 Pump (my equable.) 45 
 
 71 Pump, triple, in one column. 
 
 72 Pump (portable) worked by pedals 
 
 73 Punch Machine for Engravers. 
 
 74 Punch Machine on another prin- 
 ciple 
 
 75 Do. rotatory, for my Engraving 
 Machine. 
 
 R 
 
 76 Reciprocating Motion, (long) for 
 Mangles, &c. 
 
 77 Reflector parobolico conical, or 
 piano parabolical for light houses, 
 &c. 
 
 78 Regulator : (not centrifugal) for 
 Wind or Water Mills, Steam 
 Engines, &c. 
 
 78 Retrographic Machine (Machine 
 for Writing backwards) for En- 
 gravers. 
 
 80 Rotato-gyratory Churn. 
 
 S 
 
 81 Screw, with greatly diminished 
 friction. 81 
 
 82 Screws, (Machine for forging) &c. 
 
 83 Spinning Machines, (my Patent) 
 Eagles, &c. 
 
 84 Spinning Machinery : another 
 system, adapted chiefly to wool. 
 
 85 Spring, to keep a door strongly 
 closed, yet open easily. 
 
 80 Steel Yard, differential : for 
 weighing vast weights with short 
 levers. 
 
 87 Syphon, (mechanical) to expel 
 part of the water at the highest 
 point. 
 
 T 
 
 88 Tallow (Machine for cutting and 
 trying) 
 
 89 Tea-table (commodious help for 
 the) 
 
 V 
 
 90 Ventilator, rotatory, yet by pres- 
 sure. 
 
 91 Vessel (expanding) for Pumps, 
 Steam Engines, &c. 
 
 W 
 
 92 Washing Apparatus : for Hos- 
 pitals, &c. confining the offensive 
 ma'ter until cleansed away : thus 
 promoting salubrity. 
 
 93 Water-wheel, (horizontal) pro- 
 bably the best of the impulsive 
 kind. 
 
 94 The same, for high falls. 
 
 95 Water-wheel, (inclined) employ- 
 ing the weight of the fluid. 
 
 96 Water, (Machine for raising large 
 quantities. 
 
 97 Weaving by Power : manner of 
 driving the Shuttle, (executed 
 A. D. 1780.) 
 
 98 Wedge Machine (perpetual) 
 
 99 WHEELS (my System of cog or 
 toothed ) 
 
 100 Windmill of great oower. 
 
ERRATA. 
 
 Page 16, line 17, for fig. read plate. 
 
 22, , 4, for posistion, read position. 
 
 22, , 7, for 17, read 15. 
 
 22, , 9, for fig. read plate. 
 
 22, , 23, for fig. read plate. 
 
 24, , 16, for clylinder at P, read cylinder at K. 
 
 24, , 22, for fig. read plate. 
 
 26, , 16, for E, read C. 
 
 28, , 5, for diamenter, read diameters. 
 
 35, , 10, for inconvencies, read inconveniences. 
 
 36, , 8, for of pulley, read of the pulley. 
 
 40, , 25, for as, read of. 
 
 41, , 4, for loose 1 ; read loose 
 41, , 5, for pulleys, read pulley. 
 
 43, , 18, for furnish surplus, read furnish a 
 
 surplus. 
 
 43, ,, 22, for occpied, read occupied. 
 
 age 46, line 17, 
 
 49, 
 
 22, 
 
 55, 
 
 21, 
 
 55, 
 
 24, 
 
 55, 
 
 26, 
 
 55, 
 
 28, 
 
 58, 
 
 - 23, 
 
 62, 
 
 2 
 
 62, 
 
 8, 
 
 63, 
 
 7, 
 
 64, 
 
 2, 
 
 66, 
 
 11, 
 
 67, 
 
 7, 
 
 68, 
 
 2, 
 
 75, 
 
 4, 
 
 82, 
 
 16, 
 
 83, 
 
 11, 
 
 for power, read motion. 
 
 for diffential, read differential. 
 
 for 20,200, read 20200. 
 
 for 99,990, read ,99990. 
 
 for figures, read figure. 
 
 end the quotation marks at " lifting.' 
 
 for gasping, read anxious. 
 
 for wishd, read wished. 
 
 for ladders, read ladder. 
 
 for occasionaly, read occasionally. 
 
 for G N, read L N. 
 
 for two hundred, read three hundred. 
 
 for SOOfts. read lOOtbs. 
 
 for fig. 9, read fig. 10. 
 
 for an of inch, read of an inch. 
 
PART SECOND. 
 
 A NEW CENTURY OF 
 
INTRODUCTION. 
 
 IN the progress of a work like the present, no competent 
 reason could have been assigned for omitting to bring forward 
 my System of Toothed Wheels, the Patent for which has lately 
 expired: a System which a few years ago, excited in this 
 town, so much interest, aroused so much animosity, and was 
 treated with so much illiberality : But which, also, was fos- 
 tered with so much public spirit, tried with so much candour, 
 and adopted with so much confidence. It was I say, incum- 
 bent on me to bring the merits of this System into public view, 
 had it only been to justify myself for proposing, and my friends 
 for adopting it. But stronger reasons point now to the same 
 measure. From the intimate connection the System holds with 
 the subjects of this essay, it must be often adverted to ; and 
 I have been already obliged to speak of it in terms which can 
 hardly have been understood by those readers who had not 
 previously considered the general Subject. I should therefore 
 be still in danger of filling these Pages with unintelligible as- 
 sertions, did I not begin by marking out the foundations on 
 which my statements are built ; or by explaining to a certain 
 degree, the Principles of the new System. Without then 
 abandoning the tacit engagement I have taken with my un- 
 learned readers not to entangle them in too much theory, 
 I think it indispensable to quote the Memoir I read before 
 the Literary and Philosophical Society of Manchester, in 
 
 x2 
 
90 
 
 December, 1815 ; which small work will form the basis of 
 the practical remarks I shall have to make on the subject, as 
 this work proceeds. The Memoir is thus introduced in the 
 transactions of that learned body : 
 
 MEMOIR 
 
 ON A NEW SYSTEM OF 
 
 COG OR TOOTHED WHEELS, 
 
 By Mr. James White , Engineer.* 
 
 COMMUNICATED BY T. JARROLD, M. D. 
 
 (Read December 2Wt. 1815.^ 
 
 A HE subject of this paper, though merely of a mechanical 
 nature, cannot fail to interest the Philosophical Society of a 
 town like Manchester, so eminently distinguished for the prac- 
 tice of mechanical science ; unless as I fear may be the case, 
 my want of sufficient theoretic knowledge or of perspicuity in 
 the explication, should render my communication not com- 
 pletely intelligible. To be convinced of the importance of the 
 subject, we need only reflect on the vast number of toothed 
 
 * N. B. A Patent was taken out for the Invention some years ago. 
 
91 
 
 wheels that are daily revolving in this active and populous 
 district, and on the share which they take in the quantity 
 and value of its productions ; and it is obvious that any inven- 
 tion tending to divest these instruments of their imperfections, 
 whether it be by lessening their expence, prolonging their du- 
 ration, or diminishing their friction, must have a beneficial 
 influence on the general prosperity. Now I apprehend that all 
 these ends will be obtained in a greater or less degree, by 
 having wheels formed upon the new system. 
 
 I shall not content myself by proving the above theoretically, 
 but shall present the society with wheels, the nature of which 
 is to turn each other in perfect silence, while the friction and 
 wear of their teeth, if any exist, are so small as to elude com- 
 putation, and which communicate the greatest known velocity 
 without shaking, and by a steady and uniform pressure. 
 
 Before I proceed to the particular description of my own 
 wheels, I shall point out one striking defect of the system now 
 in use, without reverting to the period when mechanical tools 
 and operations were greatly inferior to those of modern times. 
 Practical mechanics of late, especially in Britain, have acci- 
 dentally hit upon better forms and proportions for wheels than 
 were formerly used ; whilst the theoretic mechanic, from the 
 time of De la Hire, (about a century ago) has uniformly 
 taught that the true form of the teeth of wheels depends upon 
 the curve called an epicycloid, and that of teeth destined to 
 
92 
 
 work in a straight rack depends upon the simple cycloid. The 
 cycloid is a curve which may be formed by the trace of a nail 
 in the circumference of a cart wheel, during the period of one 
 revolution of the wheel, or from the nail's leaving the ground 
 to its return ; and the epicycloid is a curve that may be formed 
 by the trace of a nail, in the circumference of a wheel, which 
 wheel rolls (without sliding) along the circumference of ano- 
 ther wheel. 
 
 Let A B (Plate 13, fig. 1.) be part of the circumference of 
 a wheel A B Fto which it is designed to adapt teeth, so formed 
 as to produce equable motion in the wheel C, when that of the 
 wheel A J5 F is also equable. Also, let the teeth so formed, 
 act upon the indefinitely small pins r, i 9 t, let into the plane of 
 the wheel C, near its circumference. To give the teeth of the 
 wheel A jB F a proper form, (according to the present pre- 
 vailing system) a style or pencil may be fixed in the circumfer- 
 ence of a circle D equal to the wheel C, and a paper may be 
 placed behind both circles, on which by the rolling of the circle 
 D on A jB, will be traced the epicycloid d, e, f, g, s, h, of 
 which the circle A B F is called the base, and D the gene- 
 rating circle. Thus then the wheel to which the teeth are to 
 belong is the base of the curve, and the wheel to be acted upon 
 is the generating circle ; but it must be understood that those 
 wheels are not estimated in this description at their extreme 
 diameters, but at a distance from their circumferences suffi- 
 cient to admit of the necessary penetration of the teeth ; or, as 
 
93 
 
 M. Camus terms it, where the primitive circles of the wheels 
 touch each other, which is in what is called in this country 
 the pitch line. 
 
 Now it has heen long demonstrated by mathematicians, that 
 teeth constructed as above would impart equable motion to 
 wheels, supposing the pins, r, i, t, &c. indefinitely small. 
 This point therefore need not be farther insisted upon. 
 
 So far the theoretic view is clear; but when we come to prac- 
 tice, the pins r, i, t, previously conceived to be indefinitely small, 
 must have strength, and consequently a considerable diameter, 
 as represented at 1, 2; hence we must take away from the area 
 of the curve a breadth as at v and n = to the semidiameter 
 of the pins, and then equable motion will continue to be pro- 
 duced as before. But it is known to mathematicians that the 
 curve so modified will no longer be strictly an epicycloid; and it 
 was on this account that I was careful above, to say that the 
 teeth of wheels producing equable motion, depended upon that 
 curve ; for if the curve of the teeth be a true epicycloid in the 
 case of thick pins, the motion of the wheels will not be equable. 
 
 I purposely omit other interesting circumstances in the appli- 
 cation of this beautiful curve to rotatory motion ; a curve by 
 which I acknowledge that equable motions can be produced, 
 when the teeth of the ordinary geering are made in this man- 
 ner. But here is the misfortune : besides the difficulty of exe- 
 
94 
 
 curing teeth in the true theoretical form, (which indeed is 
 seldom attempted), this form cannot continue to exist; and hence 
 it is that the best, the most silent geering becomes at last 
 imperfect, noisy and destructive of the machinery, and es- 
 pecially injurious to its more delicate operations. 
 
 The cause of this progressive deterioration may be thus ex- 
 plained : Referring again to fig. 1, we there see the base of the 
 curve A J5 divided into the equal parts a b, be, and c d ; and 
 observing the passage of the generating circle D, from the 
 origin of the curve at d, to the first division c on the base, we 
 shall find no more than the small portion d e, of the curve 
 developed, whereas a second equal step of the generating circle 
 c by will extend the curve forward from e to f, a greater dis- 
 tance than the former ; while a third equal step a b, will ex- 
 tend the curve from /"tog-, a distance greater than the last ; and 
 the successive increments of the curve will be still greater, as 
 it approaches its summit ; yet all these parts correspond to 
 equal advances of the wheel, namely, to the equal parts a b, 
 b c and c d of the base, and to equal ones of rotation of the 
 generating circle. Surely then the parts s g, g f, of the epi- 
 cycloidal tooth will be worn out sooner than those f e, e d, 
 which are rubbed with so much less velocity than the other, 
 even though the pressure were the same. But the pressure 
 is not the same. For, the line a g is the direction in which the 
 pressure of the curve acts at the point g, and the line p q, is 
 the length of the lever -arm on which that pressure acts, to turn 
 
95 
 
 the generating circle on its axis (now supposed to be fixt ;) 
 but, as the turning force or rotatory effort of the wheels, 
 is by hypothesis uniform, the pressure at g must be in- 
 versely as p q ; that is, inversely as the cosine of half the 
 angle of rotation of the generating circle ; hence it would be 
 infinite at s, the summit of the curve, when this circle has made 
 a semi-revolution. 
 
 Thus it appears that independently of the effects of percus- 
 sion, the end of an epicycloidal tooth must wear out sooner than 
 any part nearer its base, (and if so, much more it may be sup- 
 posed of a tooth of another form;) and that when its form is 
 thus changed, the advantage it gave must cease, since nothing 
 in the working of the wheel can afterwards restore the form,, 
 or remedy the growing evil. 
 
 Having now shewn one great defect in the common system 
 of wheels, I shall proceed to develope the principles of the new 
 system, which may be understood through the medium of the 
 three following propositions. 
 
 1 . The action of a wheel of the new kind on another with 
 which it works or geers is the same at every moment of its 
 revolution, so that the least possible motion of the circum- 
 ference of one, generates an exactly equal and similar motion 
 in that of the other. 
 
 Y 
 
96 
 
 2. There are but two points, one in each wheel, that neces - 
 sarily touch each other at the same time, and their contact 
 will always take place indefinitely near the plane that passes 
 through the two axes of the wheels, if the diameters of the 
 latter, at the useful or pressing points are in the exact ratio of 
 their number of teeth respectively ; in which case there will be 
 no sensible friction between the points in contact. 
 
 3. In consequence of the properties above-mentioned, the 
 epicycloidal or any other form of the teeth, is no longer indis- 
 pensible ; but many different forms may be used, without dis- 
 turbing the principle of equable motion. 
 
 With regard to the demonstration of the first proposition, I 
 must premise an observation of M. Camus on this subject, in 
 his Mechanics, 3d. part, page 306, viz. " if all wheels could 
 " have teeth infinitely fine, their geering, which might then 
 be considered as a simple contact, whould have the property 
 required, [that of acting uniformly] since we have seen that a 
 wheel and a pinion have the same tangential force, when the 
 motion of one is communicated to the other, by an infinitely 
 small penetration of the particles of their respective circum- 
 
 ferencies. 
 
 " 
 
 Now suppose that on the cylindrical surface of a spur-wheel J5 
 c, (fig. 3) we cut oblique or rather screw -formed teeth, of which 
 
97 
 
 two are shewn at a c, b d, so inclined to the plane of the wheel, 
 as that the end c of the tooth a c may not pass the plane of the 
 axes A B c, until the end b of the other tooth b d has arrived 
 at it, this wheel will virtually he divided into an infinite number 
 of teeth, or at least into a numher greater than that of the 
 particles of matter, contained in a circular line of the wheel's 
 circumference. For suppose the surface of a similar, but longer 
 cylinder, stripped from it and stretched on the plane A B C E 
 fig. 4) where the former oblique line will become the hypo- 
 thenuse B C, of the right angled triangle C A B, and will 
 represent all the teeth of the given wheel, according to the 
 sketch E G at the bottom of the diagram. Here the lines A 
 J5 and C E, are equal to the circumference of the base of the 
 cylinder, and A C and B E to its length ; and if between A 
 and jB, there exist a number, m, of particles of matter, and 
 between A and C a number, n, the whole surfaced JB CE will 
 contain m n particles, or the product of m and n; and the line J5 
 C, will contain a number = v 2 +% from a well known theo- 
 rem ; whence it appears that the line jB C is necessarily longer 
 than A B, and hence contains more particles of matter.* 
 
 * It need hardly be observed, that whatever is true of the whole triangle CAB, (fig. 4) 
 is true of every similar part of it, be it ever so small : and in fact, when the hypothenuse B 
 C, is folded again round the cylinder, from which we have supposed it stripped, the acting 
 part will be very small indeed ; but it will still act in the way here described, and give ten- 
 dencies to the wheel it acts on, and to its axis, precisely proportionate to the quantities here 
 mentioned 
 
 Y2 
 
98 
 
 It is besides evident, that the difference between the lines 
 B C and A B, depends on the angle A C B ; in the choice of 
 which, there is a considerable latitude. For general use how- 
 ever, I have chosen an angle of obliquity of 15, which I shall 
 now assume as the basis of the following calculations, The tan- 
 gent of 15, per tables, is in round numbers 268 to radius 1000; 
 and the object now is to find the number of particles in the 
 oblique line B C, when the line A B, contains any other 
 number, t. 
 
 By geometry, B C (x) = ^,*+t viooolH- HP* = 1035 nearly; 
 and this last number is to 268, as the number of particles in 
 the oblique line B C is to the number contained in the circum- 
 ference A By of the base of the cylinder. Hence it appears, 
 that a wheel cut into teeth of this form, contains (virtually) about 
 four times as many teeth, as a wheel of the same diameter, but 
 indefinitely thin, would contain. And the disproportion might 
 be increased, by adopting a smaller angle. 
 
 Thus I apprehend it is proved, that the action of a wheel of 
 this kind, on another with which it geers, is perfectly uniform 
 in respect of swiftness ; and hence the proof that it is likewise 
 so, as to the force communicated. 
 
 Before I proceed to the second proposition, I ought perhaps 
 to anticipate some objections that have been made to this sys- 
 tem of geering, and which may have already occurred to some 
 gentlemen present. For example, it has been supposed that the 
 
99 
 
 friction of these teeth, is augmented by their inclination to the 
 plane of the wheel; but I dare presume to have already proved, 
 that it is this very obliquity, joined to the total absence of motion 
 in direction of the axes, that destroys the friction, instead of 
 creating it. I acknowledge however, that the pressure on the 
 points of contact, is greater than it would be on teeth, parallel 
 to the axes of the wheels, and I farther concede that this pres- 
 sure tends to displace the wheels in the direction of the axes, 
 (unless this tendency is destroyed by a tooth, with two opposite 
 inclinations.) But supposing this counteraction neglected, let 
 us ascertain the importance of these objections. First, with 
 regard to the increase of pressure on the point D of the line 
 B C, (representing the oblique tooth in question,) relative to 
 that which would be on the line B E, (which represents a tooth 
 of common geering :) let A D be drawn perpendicular to JS 
 C. If the point D can slide freely on the line B C, (and this 
 is the most favourable supposition for the objection,) its pres- 
 sure will be exerted perpendicularly to this line ; and if the 
 point A, moves from A to B, the point Z>, leaving at the 
 same moment the point A, and moving in direction A Z>, 
 will only arrive at D in the same time, its motion having been 
 slower than that of A, in the proportion of A B to A D ; 
 whence by the principle of virtual velocities, its pressure on 
 B C is to that on A C, as the said lines A B to D A. 
 
 To convert these pressures into numbers, according to the 
 above data ; we have A C= 1000, A B = 268, BC = 1035 ; 
 
100 
 
 then from the similar triangles B A C, B D A, it will be B 
 C: AC: A B: A D = ~ = 259 nearly. Therefore the 
 pressure on B C, is to that on A C, as 268 to 259, or as 
 1035: 1000. 
 
 To find what part of the force tends to drive the point B, in 
 the direction B E, (for this is what impels the wheels, in the 
 direction of their axes,) we may consider the triangle B A C as 
 an inclined plane, of which B C is the length, and A B the 
 height ; and the total pressure on C B, which may be repre- 
 sented by C By (1035) may be resolved into two others, namely, 
 A B and A C, which will represent the pressures on those 
 lines respectively, (268 and 1000-) Hence the pressure on jB 
 C, is augmented only in the ratio of 1035 to 1000, or about 
 2 y part by the obliquity ; and the tendency of the wheels to 
 move in the direction of their axes, (when this angle is used,) 
 
 OQ 
 
 is the j05o of the original stress, that is, rather more than one 
 quarter. But since the longitudinal motion of an axis can be 
 prevented by a point almost invisible applied to its centre, it 
 follows that the effect of this tendency can be annulled, without 
 any sensible- loss of the active power. It may be added, that 
 in vertical axes, those circumstances lose all their importance, 
 since whatever force tends to depress the one and increase 
 its friction, tends equally to elevate the other, and relieve its 
 step of its load ; a case that would be made eminently useful, 
 by throwing a larger portion of pressure on the slow -moving 
 axes, and taking it off from the more rapid ones. 
 
We now proceed to the second proposition. The truth of 
 the assertions, contained in this proposition, must, I should 
 suppose, be evident, from the consideration of two circles 
 touching each other, and at the point of contact, coinciding 
 with their common tangent at that point. Let A and B be two 
 circles, tangent to each other, (fig 3) in e. A C is the line 
 joining the centres, and D Fthe common tangent of the circles 
 at e; which is at right angles with A C; and so are the circum- 
 ferencies of the two circles at the point e. For the circles and 
 tangent coincide for the moment. Hence then I conclude, 
 1st that a motion (evanescently small) of the point common to 
 the three lines, can take place without quitting the tangent D 
 F : and 2d. that if there is an infinite number of teeth in these 
 circles, those which are found in the line of the centres, will 
 geer together in preference to those which are out of it, since 
 the latter have the common tangent, and an interval of space 
 between them. 
 
 The truth of this proposition (or an indefinite approximation 
 to truth,) may be deduced from the supposition that the two 
 circles do actually penetrate each other. To this end let A JB 
 a by in fig. 5, be two equal circles, placed parallel to each 
 other in two contiguous planes, so as for one to hide the 
 other, in the indefinitely small curvilinear space d f e g. I 
 say that if the arc d g is indefinitely small, the rotation of the 
 two circles will occasion no more friction between the touching 
 surfaces, g ef&ndfdg, than there would be between the two 
 
102 
 
 circles placed in the same plane, and touching at the point n 
 the same common tangent. 
 
 For draw the lines D E, f d, d g, g f, g e and g D ; and 
 adverting to the known equation of the circle, let d n <#, g n, 
 = y and D g == a, the absciss, ordinate and radius of the cir- 
 cle ; we have 2 a oc a? = y 2 . From this equation we obtain 
 a = y ~2# ? the denominator of this fraction (2 oc) being the width, 
 d e, of the touching surfaces, fdg, and f eg of the two circles. 
 But the numerator (y*+ # 2 ) is equal to the square of the chord 
 g d of the angle E ID g, which chord I shall call z ; then we 
 have a = ^ from which equation we derive this proportion, 
 u : z :: z : 2 oc = -^-. But in very small angles, the sines are 
 taken for the arces without sensible error ; and with greater 
 reason may the chords ; if then we suppose the arc d g, or the 
 chord s, indefinitely small, we shall find the line d e = 2 x 
 ^, indefinitely smaller; that is, of an order of infinitessimals 
 one degree lower; for it is well known that the square of evan- 
 escent quantites are indefinitely smaller than the quantities them- 
 selves. And to apply this, if the chord % represent the circular dis- 
 tance of two particles of matter found in the screw-formed tooth 
 a c,-of the wheel JB c, fig. 3, (referred to the circle a b, fig. 5), 
 that distance z will be a mean proportional between the radius 
 D g of such wheel, and the double versed sine of this incon- 
 ceivably small angle.* 
 
 -* I ought perhaps to have introduced this reasoning on the 5th. figure by observing, that 
 
103 
 
 I am aware that some mathematicians maintain, that the 
 smallest portion of a curve cannot strictly coincide with a right 
 line; a doctrine which I am not going to impugn. But however 
 this may be, it appears certain that there is no such mathe- 
 matical curve exhibited in the material world ; but only poly- 
 gons of a greater or less number of sides, according to the 
 density of the various substances, that fall under our observa- 
 tion. I shall therefore proceed to apply the foregoing theory, 
 not indeed to the ultimate particles of matter, (because I do 
 not know their dimensions,) but to those real particles which 
 have been actually measured. Thus, experimental philosophy 
 shews, that a cube of gold of inch side, may be drawn upon 
 silver to a length of 1442623 feet, and afterwards flattened to a 
 breadth of -^ of an inch, the two sides of which form a breadth 
 of 5 -g of an inch : so that if we divide the above length by 25, 
 we shall have the length of a similar ribbon of metal of ^ an 
 inch in breadth, namely, 57704 feet ; which cut into lengths of 
 an inch, (or multiplied by 24, the half inches in a foot) give 
 1384896 such squares, which must constitute the number of 
 laminae of a half inch cube of gold, or 2769792 for an inch thick- 
 ness. Let us suppose then a wheel of gold, of two feet in di- 
 ameter, the friction of whose teeth it is proposed to determine. 
 We must first seek what number of particles are contained in 
 
 every projection of every part of a screw, on a plane at right angles with the axis of such 
 screw, is a circle ; and that therefore the chord z, or the line g d, is the true projection of a 
 proportionate part 6f any line, B C, fig. 4, when wrapped round^a cylinder of equal diameter 
 with the circle a b, fig. 5. 
 
 Z 
 
104 
 
 that part of the tooth or teeth, that are found in one inch of 
 the wheel's circumference ; this we have just seen to be 2769/92 
 thicknesses of the leaves, or diameters of the particles, such as 
 we are now contemplating. 
 
 We shall now have this proportion, (see fig. 4) 268 (A jBJ : 
 1035 fJ5 C) :: 2/69/92 (no. of particles in one inch of circum- 
 ference of hase) : x = 1 0696/7 1 particles in that part of the line 
 IB C, which corresponds with that inch of the circumference. 
 Thus each of the latter particles measured in the direction A 
 JB, is equal to the fraction I069677l ths of an inch. And if that 
 fraction he taken for the arc g d, (fig. 5) then to find the length 
 of the line d e, (on which the friction of this and all other 
 geering depends) we must use this analogy ; 12 inch. (rad. of 
 wheel ) : loeiJem of an inch (chord g d): : ^^ of an inch (g d}: 
 d e, the line required = 1273050917917292 of an inch. This result 
 is still beyond the truth, as we do not know how much smaller 
 the ultimate molecules of gold are. 
 
 To advert now to some of the practical effects of this system, 
 I would beg leave to present a, form of the teeth, the sole work- 
 ing of which would be a sufficient demonstration of the truth 
 of the foregoing theory. A, ~B, (fig. 6) are two wheels of 
 which the primitive circles or pitch -lines touch each other at o. 
 As all the homologous points of any screw-formed tooth, are at 
 the same distance from the centres of their wheels, I am at 
 liberty to give the teeth a rhomboidal form, o t i; and if the 
 
105 
 
 angle o exists all round both wheels, (of which I have at- 
 tempted graphically to give an idea at D G,J in this case, 
 those particles only which exist in the plane of the tangents 
 f h, &c. and infinitely near that plane passing at right angles 
 to it through the centres A and jB, will touch each other ; 
 and there, as we have already proved, no sensible motion of 
 the kind producing friction, exists between the points in actual 
 contact. I might add, as the figure evidently indicates, that if 
 any such motion did exist, the angles o would quit each other, 
 and the figure of such teeth become absurd in practice ; but on 
 the other hand, if such teeth can exist and work usefully 
 (which I assert they can, nay that all teeth have in this system 
 a tendency to assume that form at the working points ;) this 
 circumstance is of itself a practical evidence of the truth of the 
 foregoing theory, and of what I have said concerning it. 
 
 It must have been perceived that I have in some degree anti- 
 cipated the demonstration of my third proposition, namely, 
 that the epicycloidal or any other given form of the teeth, is 
 not essential to this geering. It appears that teeth formed as 
 epicycloids, will become more convex by working ; since the 
 base of the curve is the only point where they suffer no dimi- 
 nution by friction ; w^hilst those of every other form, that like- 
 wise penetrate beyond the primitive circles of the wheels, will 
 also assume a figure of the same nature, by the rounding off of 
 their points, and the hollowing of the corresponding parts of 
 the teeth they impel ; and that operation will continue till an 
 
106 
 
 \ 
 
 angle similar to that at o, but generally more obtuse, prevails 
 around both wheels ; when all sensible change of figure or loss 
 of matter will cease, as the wheels now before you will evince. 
 
 On the right of the drawing, (fig. 6) the teeth of the wheel 
 J5 are angular, (suppose square) and those of the wheel C 
 rounded off by any curve 6, within an epicycloid. All that is 
 necessary to remark in this case is, that the teeth of the wheel 
 B must not extend beyond its primitive circle, whilst the round 
 parts of those of the wheel C, do more or less extend beyond 
 its primitive circle; whence it becomes evident, that the con- 
 tact of such teeth,, (if infinite in number) can only take place 
 in the plane of the common tangent at right angles to A B ; 
 also that if these teeth are sufficiently hard to withstand ordi- 
 nary pressure, without indentation in these circumstances, there 
 is no perceptible reason for a sensible change of form ; since 
 this contact only takes place where the two motions are alike, 
 both in swiftness and direction. A fact I am going to mention 
 may outweigh this reasoning in the minds of some, but cannot 
 invalidate it. I caused two of these wheels made of brass, to 
 be turned with rapidity under a considerable resistance for se- 
 veral weeks together, keeping them always anointed with oil 
 and emery, one of the most destructive mixtures known for 
 rubbing metals ; but after this severe trial, the teeth of the 
 wheels, at their primitive circles were found as entire as before 
 the experiment. And why ? Certainly for no other reason 
 than that they wwked without sensible friction. 
 
107 
 
 Hitherto nothing has been said of wheels in the conical form, 
 usually denominated mitre and bevel geer. But my models will 
 prove, that they are both comprehended in the system. The 
 only condition of this unity of principle is, that the axes of two 
 wheels, instead of being parallel to each other, be always 
 found in the same plane. With this condition, every property 
 above-mentioned, extends to this class of wheels, which my 
 methods of executing also include, as indeed they do every 
 possible case of geering. 
 
 Being afraid of trespassing on the time of the society, I have 
 suppressed a part of this paper, perhaps already too long ; but 
 I hope I may be indulged with a few remarks on the applica- 
 tion of those wheels to practical purposes. And first, as to 
 what I have myself seen ; these wheels have been used in seve- 
 ral important machines to which they have given much swift- 
 ness, softness or precision of motion as the case required. They 
 have done more ; they have given birth to machines of no small 
 importance, that could not have existed without them. In 
 rapid motions they do all that band or cord can perform, with the 
 addition of mathematical exactness, and an important saving of 
 power. In spinning factories these properties must be peculiarly 
 interesting; and in calico-printing, where the various delicate 
 operations require great precision of motion. In clock-making 
 also, this property is of great importance in regulating the action 
 of the weight, and thus giving full scope to the equalizing prin- 
 ciple whatever it be. I may add, it almost annuls the cause of 
 
108 
 
 anomaly in these machines, since a given clock will go with less 
 than J of the weight usually employed to move it. Another 
 useful application may be mentioned ; in flatting mills, where 
 one roller is driven by a pinion from the other, there is a con- 
 stant combat between the effort of the plate to pass equally 
 through the rollers, and the action of the common geering, 
 which is more or less convulsive. Whence the plate is puck- 
 ered, and the resistance much increased, both which circum- 
 stances these wheels completely obviate ; and many similar 
 cases might be adduced. 
 
 I shall only add, that my ambition will be highly gratified if, 
 through the approbation of this learned society, I may hope to 
 contribute to the improvement and perfection of the manufac- 
 tures of this county ; and if the invention be found of general 
 utility to my much loved country." 
 
 Subsequently to the reading of the above paper, 1 had occasion 
 to execute many wheels on this principle ; and their appearance, 
 and use, excited on the one hand much interest, and on the other 
 much opposition. I had even to complain of real injury in that 
 contest : against which I defended myself with a warmth that I 
 thought proportionate to the attack. But all this was local and 
 temporary : and writing now for a more enlarged sphere, and per- 
 haps for a more extended period, I feel inclined to lay aside every 
 consideration, but those immediately connected with the in- 
 fluence of this work on the public prosperity. I shall therefore 
 
109 
 
 avoid all reference to the names either of my friends or my oppon- 
 ents. My friends will live in a grateful heart, as long as mem- 
 ory itself shall last ; my enemies, if I have any, will be for- 
 given or, at worst, forgotten ; and my System is hence- 
 forward left to wind its way into public notice and usefulness, 
 by its own intrinsic merits. 
 
 Certain OBSERVATIONS which I was induced to make on oc- 
 casion of a re-print of the above Memoir, may assist in intro- 
 ducing what remains to be said on the subject. They com- 
 mence thus : 
 
 The foregoing little work, which first brought this subject 
 into public notice in this town, was not the only method em- 
 ployed to develope its principles, and urge its adoption. A 
 second paper was read, at the next meeting of the society, and 
 some time after, a third, at the Exchange Dining Room ; on 
 both which occasions new modes of reasoning were pursued, 
 and new kinds of proof adduced. On the first, a model was 
 exhibited of two screw-formed teeth (connected with proper 
 centres) exactly like those represented in fig. 6 ; by the action 
 of which on each other, it became manifest that teeth of this 
 angular shape do work together without inconvenience, and 
 therefore, that all sensible friction is, in this case, done 
 away. 
 
 On the latter occasion (the lecture at the Exchange) two 
 
110 
 
 other methods were brought forward, to corroborate the prin- 
 ciples before stated : (see Plate 14, fig. 1.) The first was a 
 kind of transparency, in which a line of light represented the 
 place of contact of two wheels working together ; by the partial 
 and variable obscuration of which, the successive action of 
 every portion of the teeth was clearly shewn. The second 
 method consisted of two pair of wheels, made from loaf sugar, 
 the teeth of which were cut one pair in the usual form, and 
 the other on the new principle. Here, the difference in the 
 effects of the two methods was so great, that the common teeth 
 were almost immediately worn or broken down, by the very 
 same kind of impulse that the new wheels sustained without 
 injury : and with a loss of matter almost imperceptible, since 
 many thousand revolutions of the wheels took place without 
 detaching so many grains of sugar ! 
 
 These Observations include likewise the following remarks : 
 
 
 
 In adverting to a few of the difficulties we have encountered, 
 it will appear curious that one of them should spring from a 
 most useful property of the system : but the paradox is thus 
 explained. As there is no method more effectual for giving the 
 teeth a perfect form, than working the wheels together, (co- 
 vering them with an abrasive substance) we have most fre- 
 quently chosen to depend on that important property ; and 
 have therefore set the wheels at work as they came from the 
 foundry, instead of chipping the teeth, as is usual when com- 
 
Ill 
 
 mon wheels are expected to act well in the first instance. But 
 our wheels being then full of asperities, their action would be 
 of course imperfect and noisy, till time had smoothed and equa- 
 lized the touching surfaces : a state of things that might well 
 stagger the opinion of a candid observer unacquainted with the 
 system. Happily however we can now appeal to the fact of 
 many wheels having become silent, that were once referred to 
 with triumph, as proofs of a radical defect in the principle. It 
 may not be improper to add here, that if highly finished wheels 
 were particularly desired, we would engage to cut them in 
 metal on this principle, with all the perfection of surface given 
 to common wheels by the first masters. 
 
 In the use of bevel wheels of this description (with singly in- 
 clined teeth) there is doubtless a tendency to approach toward 
 or recede from each other ; the extent of which (for cylindrical 
 wheels) has been already determined. This tendency goes, so 
 far, to give a bend to the shaft ; and, if this be very weak, to 
 create a degree of friction on the teeth as the wheels revolve. 
 It is therefore desirable that the shafts should be rather too 
 strong than too weak ; since the principle can only exist entire, 
 when the wheels in working, are kept in the same planes which 
 they occupy when at rest. This is too evident to be further 
 insisted on. 
 
 But a greater, or at least a more frequent cause of friction 
 in the wheels is the motion, endwise, of the shafts, arising 
 
 A a 
 
112 
 
 from a want of solidity in the bearers, and especially of con- 
 nection between them ; for whenever these are strongly con- 
 nected, and the shafts well fitted to their steps, all circular 
 commotion is ipso facto destroyed ; while the longitudinal ten- 
 dency produced by the teeth on the shafts is certainly an advan- 
 tage : because it prevents the shaking that often arises from 
 their vibration, endwise, when lying on unsteady bearers, 
 or on bearers between which they have too much liberty. 
 
 A few words will make known the process of reasoning by 
 which I arrived at the idea that forms the basis of this inven- 
 tion. I had been conferring with a well-known mechanical 
 character, (to whom the art is greatly indebted) and hearing 
 his observations on the advantage derived from having two 
 equal cog wheels connected together, with the teeth of the one 
 placed opposite the spaces of the other ; so as to reduce the pitch 
 one half, and the friction still more ; (since the latter follows 
 the ratio of the double versed sines of the half -angles between the 
 teeth respectively :) and no sooner had I left that gentleman, 
 than my imagination thus whispered " What that gentleman 
 says is both true and important." " But if two wheels thus 
 placed, produce so good an effect, three wheels (dividing 
 the original pitch into three), would produce a better: and 
 four, a better still : And Jive a better than that. And for 
 the same reason, an indefinite number of such wheels would 
 be indefinitely better ! We must then cut off the corners of 
 all those teeth, and we shall have one screw-formed line, that 
 
113 
 
 " will represent an indefinite number of teeth, and approach inde- 
 " finitely near to absolute perfection !" Thus did this Invention 
 originate : and it soon appeared to me, to be the nearest approach 
 of material exactitude to mathematical precision, that is to be 
 found in the whole circle of practical mechanics. For not only 
 is the relative motion of the touching points of two wheels (that 
 is their friction}, less than the distance between two of the 
 nearest particles of matter, but it is as many times less than 
 that distance, as that distance is less than the half diameter of 
 any wheel whose teeth are thus formed. 
 
 I assert therefore that these teeth, placed in proper cir- 
 cumstances, do work without sensible friction at their pitch 
 lines : as although by means of mathematical abstraction, it 
 may be possible to assign a degree of friction between them, 
 that degree cannot be realized on a material surface : and I 
 fear not the friction on mathematical surfaces, if my material 
 surfaces do not suffer from it. I take leave then to repeat, that 
 no friction can justly be said to arise from a motion, too short 
 to carry a rubbing particle from one particle of a rubbed sur- 
 face to the next ! and this is precisely the case in the present 
 instance. 
 
 Continuing to reflect on this important subject, I soon perceived 
 that the screw -formed line would give the teeth a tendency to slide 
 out of each other ; and to drive the shafts of the wheels end- 
 wise in opposite directions ; but even that evil is not great : 
 
 A a 2 
 
114 
 
 for, confining the obliquity within 15 degrees, that tendency is 
 only about one quarter of the useful effort ; and a stop acting on 
 the central points of the axes, will annul this tendency without 
 any sensible loss of power. We need not even have recourse to 
 this expedient when any good reason opposes it : for this 
 tendency can be destroyed altogether by using two opposite 
 inclinations : giving the teeth the form of a V on the surface of 
 the wheels a method which I actually followed on the very 
 first pair I ever executed, which I believe are now in the 
 Conservatory of Arts at Paris. 
 
 A circumstance somewhat remarkable deserves to be here 
 noticed. In the specification of a Patent which I have seen in 
 a periodical work since my return from Paris, for things res- 
 pecting steam engines, and dated, if I recollect right, in 1804 
 or 5, this V formed tooth is introduced as an article of the spe- 
 cification, yet having no connection whatever with its other sub- 
 jects ; nor being attended with the most distant allusion to the 
 principle of this geering. The fact is that I had these V wheels 
 in my Portique, in 1801, when that exhibition took place in 
 which my Parallel motion appeared and was rewarded by a 
 Medal from Bonaparte : so that two of my countrymen at least, 
 engineers like myself, appear to have taken occasion from that 
 exhibition, to draw my inventions from France to England a 
 thing by no means wrong in itself nor displeasing to me : who 
 was then totally precluded from holding any communication of 
 that kind with my native country. 
 
115 
 
 It would be repeating the statements contained in the fore- 
 going memoir, to say more on the general principles of this 
 System. I request therefore, my readers to give that paper an 
 attentive perusal ; and to accept the following recapitulation of 
 its contents : 
 
 1. To cut teeth of this form in any wheel is, virtually, to 
 divide it into a number of teeth as near to infinite, as the small- 
 ness of a material point is to that of a mathematical one. 
 
 2. By the use of these teeth, and the multitude of contacts suc- 
 ceeding each other thence arising, all perceptible noise or 
 commotion is prevented. (This of course supposes good execu- 
 tion, or long -continued previous working.) 
 
 3. For the same reasons, all sensible abrasion is avoided : 
 for we have proved that the passage of any point of one wheel, 
 over the corresponding point of another, is indefinitely less than 
 the distance between the nearest particles of matter. (This 
 supposes the action confined to the pitch line of the wheel; and 
 this it will be in all common cases since the teeth wear each 
 other in preference, within and without that line ; which there* 
 
 fore must remain prominent. ) 
 
 4. From the foregoing it appears that the teeth of two wheels 
 working together tend constantly to assume a form more and 
 
116 
 
 more perfect : as they abrade each other while imperfect, and 
 cannot wear themselves beyond perfection. 
 
 5. For a similar reason the division of the teeth cannot re- 
 main unequal : for those that are too far distant from a given 
 
 tooth will be attacked behind, and those that are too near 
 
 
 
 before ; so that the division also will finally become perfect. 
 
 But it must be remembered that these recoveries of form are 
 in their nature very slow ; since the nearer the teeth come to 
 perfection the slower is their approach to it : so that in thus 
 dwelling on these properties, we do not advise the making of 
 bad wheels that they may become good; but only wish to 
 destroy an honest prejudice that has already much impeded the 
 progress of the System ; namely, that it requires great nicety to 
 adjust them so as to work together at all : which is (to say 
 the least) a very great error. 
 
 In Plate 14, fig. 1, I have shewn the apparatus presented at 
 the Exchange, as mentioned in page 110 preceding. A J$ is 
 the stand ; C D is a disk turning on the centre E ; b a is the 
 transparent line cut through the stand, and representing the 
 place of contact of two wheels geering together. It is there 
 seen, (supposing the disk to turn in the direction of the ar- 
 row) that the action of the teeth, is always progressive along 
 the transparent line a b ; whether the single or double obliquity 
 
117 
 
 * 
 
 G or F be used. In reality, the lower end of any tooth c, does 
 not uncover the line a b, till the upper point of the succeeding 
 tooth d has begun to cover it; whereas, observing a few of the 
 common teeth represented at H, as directed to the centre of 
 the disk, they would be seen to pass the line a b all at once ; 
 and thus to represent, with a certain exaggeration, the transient 
 manner of acting of the common geering. 
 
 Some knowledge of the nature of this geering may be ga- 
 thered from its very appearance : see fig. 5 Plate 14. To re- 
 present these teeth properly, no light must appear between 
 them. The tops of the teeth offer a continued circular line, 
 similar to what it would be if there were no teeth at all : and 
 the latter are distinguished only by a different shading of their 
 front and lateral surfaces. The reason (as has been al- 
 ready observed) is, that they are necessarily so placed, as that 
 the last end of any tooth shall not quit the plane of the centres, 
 until the first end of the succeeding tooth arrives at it ; which 
 principle precludes the possibility of any space remaining be- 
 tween the teeth, that an eye directed parallelly to the axes 
 could penetrate. Such a space indeed would introduce a por- 
 tion of the properties of the old geering, which it is the object of 
 this System to avoid. As this wheel then appears in fig. 5, so 
 it acts : that is equally and perpetually. 
 
 It were well also to observe the appearance of these wheels 
 on their edges ; or in the planes which, as wheels they occupy. 
 
118 
 
 The 4th. figure of this Plate is outlined with some care, in 
 order to shew the varying, and seemingly anomalous form 
 which the teeth assume as they approach the boundaries of the 
 figure. Although cut as obliquely to the axis there, as any 
 where else, the receding cylindrical surface, thus seen, appears 
 to take this obliquity away ; and the very outward teeth seem 
 nearly parallel to the axis of the wheel. But this is only ap- 
 pearance : and we give here one example of it, that we may 
 not be obliged to lose much time hereafter, in drawing cor- 
 rectly, wheels on this principle a process indeed which in 
 many cases, would be found very difficult, if not impossible. 
 
 We have already adverted to the oblique tendencies of these 
 wheels, when used with a single inclination of the teeth ; from 
 which, among other things, it follows that, in the act of urg- 
 ing the shafts endwise, they tend also to bend these shafts : 
 for which reason the shafts require to be stronger than those of 
 common wheels that is, when the effort bears any proportion 
 to their stiffness a circumstance which, in light rapid move- 
 ments, is of small moment. And in heavier works, when it is 
 desirable to get rid of these tendencies altogether, we have per- 
 emptory means of avoiding the very appearance of this evil. 
 
 Suppose then (fig 2 and 3, plate 14) a b to be a straight 
 rack on this principle ; driven by the wheel or pinion c. The 
 motion, backward, of the pinion, tends, clearly, to urge the 
 pinion endwise towards d, and the rack side ways towards a b. 
 
119 
 
 But either of these motions is prevented by fixing to the pinion, 
 or the rack, a cheek e f, to support them against this lateral 
 pressure. But then, exclaims a doubting friend, you intro- 
 dnce friction : and it is true : there is now a real rubbing of 
 the ends of the teeth against this cheek ; but the pressure 
 there being only one quarter of what it would be on the front 
 of straight teeth, we avoid (on a rough estimate) three quar- 
 ters of the friction ; while preserving all the constancy and 
 smoothness of motion which the system gives ; and which after 
 all, is the most important part of the business. 
 
 This idea then applies among other things to the racks of 
 slide -lathes ; giving a regular motion to the rest and cutting 
 tool, thereby adding to the perfection of the turning process : 
 and many other cases might be adduced. 
 
 But instead of using a rack and pinion, as thus described, 
 two wheels, of any desired proportions might have been thus 
 treated, and the result would have been the same. They would 
 have worked with perfect smoothness, under about one quarter 
 of the friction attendant upon common wheels in similar cir- 
 cumstances. There are cases therefore, in which it would be 
 expedient thus to employ the System. I cannot but observe 
 likewise, that this method of using cheeks to prevent any side 
 motion in spur wheels, might also be applied to bevel- wheels, to 
 prevent the angular tendency which the obliquity of their teeth 
 gives them : and that I prefer such a method of obviating this 
 
 Bb 
 
120 
 
 evil (where it is one) to any attempt at using teeth in the V 
 form, on bevel wheels. Still however, as before observed, this 
 counteraction of the oblique tendencies is not always necessary. 
 It may be dispensed with in all light and rapid movements ; 
 especially in the use of perpendicular shafts ; and where the 
 driven wheels are small and distributed round a central wheel 
 in positions nearly opposite each other : of all which cases we 
 shall see examples in the spinning machinery to be described 
 hereafter. 
 
121 
 
 OF 
 
 THE CUTTING ENGINE, 
 
 To form Spur -wheels, on my late Patent principle. 
 
 A HE figures of this Engine (see Plates 15 and 16,) are drawn 
 to a scale, from the Machine itself, now before me. The scale 
 of the objects on Plate 15, is one inch and three quarters to 
 the foot ; and that of the objects on Plate 16, one inch and one 
 third. These were convenient proportions for introducing this 
 object into the present work; but the size itself of the Machine 
 is arbitrary. I did not make it according to my ideas of the best 
 dimensions : but bought it as a common cutting Engine, and 
 gave it those other properties that my System required. 
 
 The first remarkable deviation from the usual form is in the 
 shaft or axis of the dividing plate. See fig. 1 and 2 of the 
 Plates 15 and 16. The dividing plate a b, is concentric with, 
 and fixed to an axis A B made as perfectly cylindrical as pos- 
 sible, so as both to slide and turn in the bars C D, and E F 
 composing the frame. These bars are bushed, to fit the axis 
 A B, either with a contracting ring of brass, as usual in some 
 mathematical instruments ; or with type metal, cast around 
 the axis into rough holes in those bars : which metal, closing 
 upon the axis makes a good centre ; and will last a long time. 
 My Engine is made in this manner ; and has been renewed in 
 
 Bb2 
 
122 
 
 this part only twice in several years. This frame C D E F of 
 the Engine, is strongly connected with the feet G G H H, by 
 means of the nuts E F in the plan : and by these feet it is 
 fixed to its bench or table, as will be seen in Plate 16. 
 
 Figure 2 of the present Plate, represents the plan of the Ma- 
 chine, but turned upside down ; so that the feet G H screwed 
 under the lower plate E F, are wholly visible. In this figure, 
 also, is shewn at c d, the edges (without the bottom) of the 
 horizontal slide which carries the stand for the cutter frame 
 represented in fig. 4. This stand is indicated by the dotted 
 lines of this figure 2, as situated under the arm D of the bar C 
 D ; but it is better shewn in fig. 5, where e f marks the slide 
 in which the cutter frame (fig. 4) moves up and down, by means 
 of the screw and handle e f. In general I avoid dwelling much 
 on these smaller parts, because they exist, probably in a more 
 perfect state, in most other machines. In this fig. 5, g h 
 shews the screw that moves this stand nearer to, or further 
 from the axis A ~B of the Engine, according to the diameter of 
 the wheels : which is also a common process in Machines of 
 this kind, on which therefore much need not be said. But a 
 somewhat greater importance attaches to the cutter frame re- 
 presented in the 4th. figure : which is a kind of small lathe 
 whose spindle n o, carries the cutter n, outside the frame, for 
 the purpose of changing the former without ^displacing the 
 latter. The cutter (of any proper section) is placed in or near 
 that line which is a continuation of the centre of the fixing 
 
123 
 
 screw o p. It is in that line for wheels whose teeth can be 
 finished with once cutting : but near it for those whose teeth 
 must be cut at twice. In this same figure, i k represent the 
 ends of the standards that form the vertical slide e f of fig. 5 ; 
 and the separate figure p q, shews the back of the cutter frame 
 / m, the flat part of which, p, presses correctly on these up- 
 rights i k, and thus fixes this instrument at any desired height, 
 and to any given angle with the perpendicular : the use of which 
 arrangement we shall soon have occasion to exemplify. 
 
 Turning now to fig. 3 of this Plate, we there see the main 
 shaft A J5, broken off at jB : and the letters a b again shew the 
 dividing plate of figs. 1 and 2 : under this Plate is seen an ali- 
 dade or moveable index, shewn by section only at c, and in 
 elevation at d e ; where it clips the plate as far as n and carries 
 a boss between n and e, on which the dividing index ef, turns; 
 and to which it is strongly fixed by a nut o, when the proper num- 
 ber to be cut is determined. Moreover, this boss forms, itself, the 
 nut of a thumb -screw s, which, carrying a circular plate at its 
 lower end, clothed with leather or any soft substance, con- 
 nects strongly, without injuring the plate, the moveable index 
 with any point of it, as determined by the dividing index e f. 
 This brings us into the midst of things, as it respects the use of 
 this Engine ; for the former index c d, is furnished with a small 
 roller, p, the motion of which all the foregoing objects must 
 obey, when they have been fastened together by the thumb- 
 screw s. We turn then to the figures 1 and 2 of Plate 16, in 
 
124 
 
 order to shew those parts in action : after remarking only that 
 the form p q r of this fig. 3, is that of the moveable index 
 shewn before at c d; requiring only, to become complete, 
 that the part q should be sufficiently lengthened to make the 
 arc r q a complete semi-circle for purposes that will shortly 
 be explained. 
 
 In the two figures of Plate 16, the Machine is shewn as 
 placed on its bench or table, accompanied by the parts which 
 give it a distinctive character, and in fact embody the System. 
 In addition to the parts already described, we first remark the 
 circular rim c d, fixed to the ends of the bar E F ; and made 
 perfectly concentric with the main shaft A B, and the divid- 
 ing plate a b. This rim is shewn in section only, at v fig. 2. 
 Its section resembles an L, and thus forms a basis for certain 
 plates that will soon appear ; and receives the screws by which 
 these plates are fastened to it. This being sufficiently clear, 
 we now proceed to describe the table and the connection of its 
 mechanism with the foregoing. 
 
 In Plate 16, K L is the table : to which the Engine is 
 screwed through its feet G H. /, is a square bar of wood, 
 sliding in a mortice through the top of the table; and connected 
 by a joint with the lever M N itself moving round a pin at O, 
 and carrying a friction roller, P, which pressed by the spiral 
 Q, as turned by the handle R, raises the bar /, and with it 
 the main axis A of the plate, and of course the wheel to be 
 
125 
 
 cut, centered as usual on this axis above B. Finally, p q r, in 
 both figures, is the moveable index first shewn in fig. 3 of Plate 
 15 ; prepared to be drawn round by a weight JV, hanging to 
 the cord x, passing over the pulley y, and tied to the right end 
 of the arc q r, when this is to move to the left ; or to its left 
 end, when the motion is to be toward the right : these mo- 
 tions depending on the right or left-handed direction of the 
 teeth which it might be wished to cut on the Machine. 
 
 Between the two figures 1 and 2 of this Plate, there appears 
 a diagram, the base of which is nothing more than a part of the 
 rim c d supposed straightened, and placed there that its use may 
 be the easier understood. On the rim is seen a right angled 
 triangle e g f, against which the roller p will lean by the 
 action of the weight W on the cord x, and the arc q r of the 
 moving index p q r. So THAT when, by the handle R, the spi- 
 ral Q depresses the lever M N, by means of its roller P, then 
 the bar I raises the axis A B of the Engine, and the weight W 
 turns it at the same time, as much as the small roller p permits 
 by rolling up the side e f of the plate e g f. And thus may a 
 screw -formed tooth be cut in any wheel centered above B in 
 the usual manner. 
 
 Thus then, in describing this Machine, the manner of using 
 it has been also shewn : for the cutter, in this Machine, (to 
 cut spur wheels) is alwaysy&m/; and all the motion is com- 
 posed of the rotatory and longitudinal movements of the princi- 
 
126 
 
 pal axis, which carries the wheel along with it. The cutter I say 
 is fixed, at a proper height just above the wheel, and at an angle 
 to the perpendicular, equal to that it is wished the teeth should 
 form on its surface. This inclination as before observed is 15 
 degrees; and the tangent of 15 is in round numbers 268, when 
 the radius is 1000. That is, in our present figure, the basis e g 
 of the plate e g f, occupies 268 divisions of a scale, of which 
 the height g f contains 1000. It appears then, that to cut a 
 tooth with 15 degrees inclination, by this Plate, the wheel re- 
 ceiving that tooth, must be just as large as the rim itself; for 
 the surface of the wheel would turn more, with a given eleva- 
 tion, if it were larger than the rim ; and would turn less, by 
 the same elevation, if it were smaller. In a word the whole 
 theory of this operation, is now clearly seen. The smaller the 
 wheel to be cut, the longer, horizontally, must be the Plate ; 
 or in other words, as the diameter of the wheel is to that of the 
 rim, CG d} so is the length e g of the Plate to its height f g. 
 Now this height fg, is always the same ; all change therefore, 
 in the plates, takes place on the horizontal length : and this 
 length is most easily found by the foregoing RULE OF THREE. 
 If then, instead of the triangle e f g, I had used the triangle 
 e' f g' it would have followed at once, that to produce an incli- 
 nation of 15 degrees, I must have taken a wheel of just half 
 the diameter of the rim ;for the plate e' f g' is just twice as long 
 as that efg. To prove this, let us suppose the diameter of a 
 wheel wanted, to equal one half that of the rim c d : then the 
 rule will stand thus : 
 
127 
 
 1 is to 2, as 268 is to ...536, the length of the plate according 
 to the theory ; which is precisely the length it is drawn to 
 compared with that e f g, namely twice as long. Thus the 
 four triangles, drawn to the right and left in this diagram, 
 represent the plates for the wheels of the following diameters 
 respectively : 
 
 No. 1, a wheel equal to the plate rim c d ; 
 
 2 do. do. to i do. 
 
 3 do. do. to i- do. 
 
 4 do. do. to J do. 
 
 A small anomaly, of form, may be mentioned here to pre- 
 vent mistakes. The shaded triangle e f g in the Plate, looks 
 higher than the rest : but if higher, it is also longer in the 
 same proportion ; and the roller p never reaches the bottom : 
 so that the effect of this Plate is the same as though it re- 
 sembled the others in every respect. In general the effect of 
 the Plates depends on their length compared with their height : 
 and indeed they must be made higher than the thickness of the 
 wheel to be cut, that the latter may disengage itself from the 
 (fixed) cutter both above and below. 
 
 It is proper to observe, that for every pair of wheels there must 
 be a pair of plates ; one leaning to the right and the other to 
 the left, (see the diagram) but, as before said, the degree of 
 obliquity must be different in each pair, except in the case 
 
 c c 
 
128 
 
 of equal wheels, when the same plate serves for both ; only 
 turning it to the right for one wheel, and to the left for 
 the other. Nor does this offer any difficulty, as the plates 
 are made of common tin plate : which is easily brought 
 to fit the rim, whichever way it is applied. I shall now add 
 another example of the process for finding the length of the 
 plates : and to that end repeat that the plate rim c d, is 22 
 inches in diameter, or 11 inches radius. Supposing then that 
 we wished to cut a pair of wheels, one of them being 1 inch 
 in diameter and the other 12 inches ; both to have teeth in- 
 clined 15 degrees to the axes ; (as without that they could not 
 work together) to do this we must effect these two proportions : 
 
 (1) J inch (radius of small wheel) is to 11 inches, (radius of 
 
 plate rim) as 268 parts (of which the height of the 
 plate is 1000) to another number, which is the length 
 of the plate sought : measured on a scale of parts of 
 the same magnitude. 
 
 (2) 6 inches, radius of the large wheel ; is to 11 inches radius 
 
 of plate rim ; as 268 parts (as before) is to another 
 number, which is the length sought for this second 
 plate. 
 
 Both proportions being effected, the first plate is 5896 parts. 
 And the second 491.33 do. 
 
 The one of course, to be directed toward the right hand, 
 
129 
 
 and the other toward the left, on the plate rim ; where note, 
 that if the height (1000 parts) is found so numerous as to 
 create confusion, let 100 parts be assumed ; when the length 
 of the plate will become 26.8 or 26 and ^ instead of 268, and 
 the operation will be so much the more simple. 
 
 It should be added that this process admits of being further 
 simplified : since the product of 11 inches, radius of the plate 
 rim, multiplied by 268 (tangent of 15 degrees, or length 
 of the plate for a wheel equal in diameter to the plate rim) 
 since this product, I say, is a constant number, namely : 2948 
 which, divided by the half diameter of any wheel, gives, at 
 once the length of the plate adapted to that operation, in 
 parts of which the height contains 1000 ; or supposing the 
 height to be 100 only, this constant number becomes (nearly 
 enough for practice) 295. In a word, on a height of plate of 
 100 parts, when wishing to cut a wheel of 2 inches in diame- 
 ter, I merely divide 295 by 2, and get for the length of my 
 plate 147.5 parts of which the aforesaid height is 100. 
 
 It may possibly be suggested that this method of using 
 plates to determine the obliquity of the teeth is an imperfect 
 method, giving some trouble in the execution, and leaving a 
 certain degree of roughness in that execution. The fact is 
 allowed ; but this method has the advantage of a very general 
 application, which many a better looking apparatus would not 
 present. 
 
 c c 2 
 
130 
 
 Besides, for most uses, these teeth require chiefly that the 
 obliquity should be correct, and not that the surface should be 
 licked like those of a gewgaw. In fine, the principle of this 
 Machine once known, its best form will occur to the reflecting 
 mechanician according to the quality of the work he has in 
 view : And in fact, in the hands of a well known artist, this 
 form has been already varied so as to produce effects much 
 higher wrought than could be drawn from the Machine above 
 described : which latter however in point of generality, still 
 preserves the advantage. 
 
131 
 
 OF 
 A DOOR-SPRING, 
 
 To keep a Door strongly closed, yet suffer it to be opened easily. 
 
 J. HAT " necessity is the mother of invention," is a remark 
 none the less true, for having become a trite proverb ; I could 
 mention the time, place, and circumstance which gave birth to 
 this little Invention : but such detail would be superfluous. A 
 certain door was, and is still, most inconvenient, from the 
 stiffness of the spring, and the noise it occasions in a place 
 where silence ought to prevail : which state of things suggested 
 to my mind the Machine represented in fig. 5, of plate VJ. 
 
 A B C in that Plate, is a horizontal section of the door, 
 door jambs, &c. The door spring now in use, is a barrel- 
 spring, with an arm carrying a small roller which presses in a 
 gutter -formed plate, screwed to the door. My door spring is 
 on a different principle. The roller is fastened in and by a 
 small frame to the door, and the arm is fixed to the axis of the 
 spring, which passes up through the top of the barrel. This 
 spring is much weaker than the former, insomuch as only just 
 to close the door by its elasticity ; but when the door is shut, 
 there is a sharp bend in the arm that wedges itself against the 
 roller, and decuples at least the force of the spring, as tending 
 to keep the door closed. When therefore it is desired to open 
 
132 
 
 the door, by pressing the door itself, a good push is necessary, 
 but only for an instant : for as soon as the bent part of the arm 
 is forced off the roller, there remains only the small resistance 
 of the spring to be overcome ; which latter, when suffered to 
 act in shutting the door, will not shut it with that noise a 
 stronger spring would occasion ; and yet, when arrived at its first 
 position, it will keep the door as strongly closed as ever. And 
 should it be wished to avoid the necessity of pushing hard 
 against the door, even at first, there is a sliding button and 
 stem B put through it, which, if pressed from the other side, 
 with the force only of the spring, will raise the latter beyond 
 the roller, and thus open the door with perfect facility : and 
 this same process will take place in pulling the door open by 
 the hook D from the inside : yet still the door when closed will 
 be as firmly so as before ; the spring-bar acting in the latter 
 position, as much like an invincible stay as the workman shall 
 have desired this property depending clearly on the nearness 
 of the bend to a right angle. 
 
 This device may appear to some an object too inconsiderable 
 to be justly dignified with the name of an invention. But if I 
 should sometimes fall into such an error as this, I intend to 
 compensate for any thing too trivial by giving in other cases, 
 Inventions of ample size and number. I might even mention 
 the Cutting Engine given in this part, where several Inventions 
 are compressed into one, or rather presented as one, of which 
 several examples will occur. 
 
133 
 
 A DRAW-BENCH, 
 
 For making my twisted Pinions. 
 
 A HE pinion wire of clock and watch makers is well known. 
 I am not wholly acquainted with the manner in which it is 
 drawn : but I have made my pinion wire, of brass, in lengths of 
 about a foot, by the Machine described below. 
 
 A common Draw -bench (not here represented) is worked in 
 the usual manner : but the instrument which forms the pinion 
 (see Plate 17) is of a peculiar construction. It consists of a 
 plate A By containing 1st. a guide tube , (fig. 2) to centre 
 and conduct the blank wire ; 2d. a ring b c, with nine grooves 
 cut 011 one of its surfaces, directed to the centre, and in which 
 are well fitted the cutters 123456/89; and 3d. a ring d e, 
 formed into nine spirals exactly like each other, answering to the 
 cutters, and destined to urge them equally toward the common 
 centre whenever this circle d e, is turned by the endless screw 
 CD, in the direction of the arrow. In fig. 2,fg is merely a top 
 piece to cover at the same time the cutters and the ring d e ; 
 which latter is thus duly centered. The points of the cutters 
 1, 2, 3, &c. are formed like the spaces of pinion teeth ; and in 
 the other direction, are sloped 15 degrees to the common axis, 
 as taken at their pitch line. 
 
134 
 
 The third figure represents the drawing clams, or pinchers, 
 with a piece of blank wire d in them, tapered off to give easy 
 entrance to the cutters. These clams have a cylindrical part 
 of about a foot long, in which is cut a winding groove a b, 
 whose use is to turn the wire in the act of drawing ; for which 
 purpose also the swivel efis provided. The method I employ to 
 trace this groove to the obliquity required, is to measure the cir- 
 cumferenceof the cylinder, and call that 268; and then, to make its 
 length, in the cylindrical part, equal to 1000 of the same divisions. 
 But this is right, only when the pinion to be drawn is of equal 
 diameter with the clam -cylinder a b : so that if it is wished to 
 draw pinions of a smaller diameter, I further say : diameter of 
 clam-cylinder is to diameter of pinion, at the pitch line ; As 
 1000 (present length of clam -cylinder) is to required length of 
 ditto. Thus, for example, if the diameter of the pinion were 
 only J that of the clam -cylinder, the length of the latter would 
 be only 250 of the 1000 divisions, before found : and so inpro- 
 portion for smaller diameters. 
 
 The figure shews this groove receiving a guide screw or stud 
 , which, placed in the fixed headstock a c, turns the clams d, 
 with the wire, just enough to give the teeth an inclination of 15 
 degrees, thus adapting them to the wheels of which the pro- 
 portions have been already given ; where note, that the real 
 dimensions of this pinion Machine are twice as large as those 
 of the figures 1 and 2 : but the size of every thing is of course 
 variable, according to the pinions required to be produced. 
 
135 
 
 OF 
 
 A GEERING CHAIN, 
 
 Formed to work in the Patent Wheels. 
 
 \. HIS Chain is shewn in fig. 4 of Plate VJ . The links are formed 
 to an angle, in the middle, similar to that of the wheels at their 
 pitch line ; of which the obliquity, for the V wheels, is greater 
 than 15 degrees ; since the thickness of the wheel, is neces- 
 sarily divided between the right and left handed slope. Be this 
 slope what it may, the chain and wheels must of course be alike, 
 measured at the pitch line of the wheels ; and then, as the 
 chain geers with a straight line of pinions, they work together 
 without sensible friction on the teeth, and with nearly the same 
 steadiness of motions as wheels would work together. More- 
 over, if the drum be of a pretty large diameter, its action will 
 likewise be nearly equable. The degree of precision depends, 
 however, on the fineness of the pitch, and the largeness of 
 diameter in the drum ; since every chain bending round a cy- 
 linder must form a polygon of a greater or less number of sides, 
 dependent on these circumstances. I repeat then, that while 
 the chain works on the pinions in a tangent to them all, there 
 is no necessary friction between them ; nor yet on the pins of 
 the chain, but only at the drums which actuate and return the 
 latter : I shall dismiss the subject, by observing, that I have 
 used the term drum, because of the similarity of this chain - 
 
 DC! 
 
136 
 
 motion to that produced by bands, where drums are generally 
 the movers. But here, this supposed drum is a wheel of proper 
 diameter, cut into teeth similar to those of the pinions ; and 
 placed at the same height on its spindle. I have reason to 
 think that this chain, carefully made, would be an useful addition 
 to the bobbin and fly frame, applied both to the bobbins and spin- 
 dles, instead of the bands now in use ; which, though a con- 
 venient resource, give a result equally uncertain and imperfect. 
 
137 
 
 OF 
 A SERPENTINE BOAT OR VESSEL, 
 
 To lessen the Expence of Traction, -c. 
 
 J, HE present description of this Machine, will consist, chief- 
 ly, of a translation from my own specification, given at Paris 
 with the application for a Brevet, or Patent, obtained in the 
 year 1795, and which is thus introduced. 
 
 " It is a well-known fact, that the longer any Boat or Ves- 
 sel is, in proportion to its width, the less power it requires to 
 convey a given load, from one place to another. But these 
 lengths cannot be extreme, without introducing a degree of 
 weakness, that would offer great danger in the use of such 
 vessels. If then a Boat of a given volume, be divided into 
 several long and narrow ones, the head of each adapted with a 
 certain exactness to the stern of its forerunner, they will (with 
 the trifling difference arising from the asperities of their sur- 
 faces) all move through the water with the same ease as any 
 single one ; and carry, unitedly, the same weight as did the 
 large Boat before it was divided. This idea constitutes the 
 principle of my Serpentine Vessel. 
 
 This Invention is not to be considered as an imitation of the 
 well-known manoeuvre of towing one vessel in the wake of 
 
138 
 
 another : for the resistance of the vessels thus towed, remains 
 nearly, though not quite the same as if drawn along separately. 
 But here, by the adaptation of the prow of one Boat to the poop 
 of another, the first alone suffers resistance from the water 
 which, although it enters between the joints, strikes only the 
 first and from this it follows, that the resistance of these ves- 
 sels, in passing from one place to another, bears no necessary 
 proportion to the weight they carry." 
 
 " Thus then, I obviate the necessity of having broad vessels 
 to carry the heaviest burdens ; for I disseminate the load over 
 an indefinite length : by which method also, my vessel rides in 
 shallower water, and depends less for its passage, on the state 
 of the rivers or the seasons. Besides, they require a much less 
 number of horses, or exertion of power, to transport a given 
 quantity of goods ; admitting at the same time, a greater 
 swiftness of motion. And finally, if these vessels travel through 
 different towns on the same voyage, the goods of each town 
 may be lodged in the same part, and merely detached in pass- 
 sing, so as to lose no time in unloading them." 
 
 " Fig. 1 of Plate 18, shews the plan of several forms which 
 I give to the articulations or separate parts of these vessels : so 
 as to connect them strongly, yet leave them, as a whole, in 
 some degree flexible. The form A J5, is, for the first boat, a 
 staight line across to form the stern, and for the second an 
 obtuse angle terminated by a semi-sphere or vertical semi-cy- 
 
Under, which enters a hollow and similar figure in the first 
 Boat which latter, in this case, forms the Head of the whole 
 Serpentine Vessel." 
 
 " These two parts or joints, of which we have been speaking, 
 are held together by a rope c d e f, which, fastened to the 
 second part at c, passes over two pulleys e d, in the head, to 
 the small capstan f, by which, both parts are bound together 
 as tightly as may be judged proper. If it were thought neces- 
 sary, the spaces jl JB might be underlined with a piece of 
 leather or metal, not to prevent the water from entering be- 
 ween the Boats, but to prevent its striking those which follow 
 the others through the water a precaution less urgent in the 
 other kind of joint we are about to describe." 
 
 " C D, in this same figure, presents another form of the 
 head and stern of two contiguous Boats or parts ; (which, to 
 save room, are both supposed to be broken off* at some point 
 between their ends :) where as in the former case, the Boats 
 are connected so as to remain horizontally flexible. These 
 forms are semi -cylindrical, the stern concave, and the head 
 convex, to the same radius; and the motion takes place around 
 a bolt and pulley p, reeved with a rope coming from one side of 
 the first Boat near C and led again to a small windlass or capstan 
 placed on the other side near D. E F, is another modifi- 
 cation of the same kind of joint : the centre of which is a bolt 
 or stud q, (better seen at q in the 2d. figure) over which a tri- 
 
140 
 
 angular frame falls from the preceding Boat, and thus connects 
 them instantaneously ; leaving a certain flexibility in the hori- 
 zontal direction." 
 
 ' ' 
 
 Finally, GH shews a simple mean of connecting these Boats, 
 on the supposition that both ends of each are formed alike to 
 an obtuse angle in the middle of their breadth. It is a kind of 
 hook r s, mounted in a frame turning on centres in the pre- 
 ceding Boat, and reaching over into the succeeding one ; where 
 it finds a hollow step of metal which receives and fits it, so as 
 to hold these neighbouring Boats with sufficient tightness, but 
 still with a certain degree of flexibility. Many other methods 
 might be suggested, by which to form these joints ; and almost 
 any might be made to answer the purpose. I shall therefore 
 leave this branch of the subject, observing only, that the se- 
 cond figure of Plate 18, is an elevation of the same things : 
 which, generally, are marked with the same letters as far as 
 they are visible/ 3 
 
 " The third figure presents the same objects in perspective ; 
 to which are now added two masts / K, placed obliquely on 
 that Boat which forms the Head of the whole vessel. This 
 obliquity is useful when the boat is drawn from one side only ; 
 but is injurious where the traction takes place indifferently 
 on both sides : so that I should not, now, advise the use 
 of this method which indeed, I have avoided in fig. 4 of this 
 Plate/' 
 
141 
 
 " In every case, each of the masts carries a pulley near / 
 K, over which passes a rope, the ends of which are fastened 
 to the masts by proper brackets, near the deck : and to the 
 middle of this rope is fastened the track rope Z/, by which the 
 horses draw the Boat along. By these means the vessel is 
 steered either to or from the land : for if the knot of the track 
 rope is brought near the mast /, the Boat (w^hich as before 
 observed is the head of the whole vessel) veers towards the 
 horses ; and the contrary when the knot is drawn towards the 
 mast K: both which effects are rendered the more prompt 
 and decisive, by the use of the lee boards K M 9 the nature and 
 use of which are already fully known." 
 
 " But there are cases in which, from its great length, this 
 Serpentine Boat would require a particular direction, for some 
 intermediate point between its extremities ; as although, in 
 theory, every separate part ought to pass through the same 
 water, yet in canals or rivers much bent, this may not invari- 
 ably take place ; and then a rudder would be useful, even in 
 the middle of the vessel. I have therefore placed a pair at P 
 R, fig. 3. Their motion is a vertical revolution, round a horizon- 
 tal centre ; and as they are formed obliquely to the sides of the 
 Boat, when one of them is plunged into the water, it tends to 
 drive the Boat in a sidewise direction : and if at any time it 
 should be desired to stop the whole vessel, both rudders would 
 be plunged at once into the water, when they would greatly 
 contribute to that effect. 7 
 
142 
 
 " The fourth figure in this Plate 18, presents a general view 
 of the vessel, comprising five articulations, (or Boats) besides 
 the head and stern which latter would fit each other without 
 any intermediate parts, and form a Boat alone. Nor do these 
 five parts by any means limit the useful number : but the Plate 
 would not have contained more, unless on a scale too small to 
 be distinctly understood." 
 
 ( ( Returning now to fig. 1 , we observe the ropes A D F H 
 and J5 C E G, which are supposed fixed to the stern Boat, 
 and carried to the capstans represented in the Head. These 
 ropes consolidate the whole fabric, and act, occasionally, as a 
 kind of muscle, to govern the larger evolutions. These ropes 
 pass in the brackets placed near the joints A B and C Z>, 
 r. being under the gang ways, of which a portion appears 
 at S fig. 3, hung upon hinges, that they may be turned up 
 when the Boat is used in narrow water." 
 
 To the above specification were added the following re- 
 marks, which still apply to this kind of vessel, navigating on 
 canals and inland rivers : " this vessel admits of the use of every 
 kind of mover ; such as men, horses, wind, or the steam en- 
 gine ; the latter of which I propose to apply to it in a man- 
 ner equally simple and effectual ; especially so as not to injure 
 the banks of any canal, &c. by acting against and disturbing 
 the water ." 
 
143 
 
 I need not repeat that this Invention dates as high as 1795 : 
 as the Brevet was issued in that year. It may he added that 
 four parts of such a Boat were executed about the same time ; 
 namely, the head, the stern, and two intermediate pieces: making 
 together a length of 100 feet ; and these, loaded to a certain depth 
 with stones, were drawn up the river Seine by a single horse 
 on a trot which would likewise have taken place had the 
 Boat been ten times as long ; since, as before mentioned, the 
 resistance of this kind of vessel bears no given proportion to the 
 Load it carries. 
 
 11 e 
 
144 
 
 OF 
 
 A MACHINE 
 
 For destroying, or lessening Friction. 
 
 J. THINK it may be assumed that friction is fully expressed by 
 the word rubbing : and that where rubbing cannot be found, 
 friction does not exist ; especially that kind of friction which 
 opposes the motion of machinery in which respect alone, the 
 subject is usually thought interesting to mechanicians. It would 
 be abandoning my intended plan in this work, to treat largely 
 of friction, or any other accident in practical mechanics ; but 
 having already declared myself ' ' no believer in several sorts of 
 friction," I am in a measure bound to introduce my description 
 of the two following articles, by a short reference to the gene- 
 ral subject. I offer then the following remarks, more as hints 
 for the consideration of learned experimenters, than as conclu- 
 sions sufficiently proved to become rules in practice. What I 
 cannot help urging strongly is, that rolling is not rubbing. If 
 it were, I would ask in what direction it takes place ? Is it in 
 that of the plane rolled over ? or in that of the radii of the 
 rolling body ? If in the former, it would indeed glide over that 
 plane, and occasion or suffer real friction ; but this, I think, 
 is not pretended. If this motion is in the latter direction, 
 (that of the radii of the rolling body) it is indefinitely short, 
 compared with the progressive motion of the rolling body, so 
 
145 
 
 that the power of the latter, to overcome any resistance in that 
 direction, is infinite. Whenever therefore, in experiments of 
 this kind, a finite resistance is perceived, it must, I should 
 think, be ascribed to other causes, and not to friction. In my 
 wheels for example, (see a former article) where there is a real 
 and deep penetration of the surfaces, I have proved that the 
 friction between the teeth is less than the distance between 
 two of the last particles of matter : and surely, when penetra- 
 tration is purposely made as small as possible (by the use of 
 smooth rollers) the friction thence arising must be still more 
 imperceptible. But I hear it answered, that this friction is both 
 known and measured ! and certain celebrated experiments are 
 adduced to prove it. But what I most wonder at is, that a 
 person so truly learned as the author of those experiments, 
 should have adopted so remarkable a misnomer ; in which to all 
 appearance, indentation has usurped the name of friction. Nor 
 let this surprise, surprise any body : nor especially, offend this 
 learned author himself; for I am persuaded that the sole act of 
 placing these wooden rollers, on these surfaces of wood, must 
 indent them both sufficiently to account for all the facts ob- 
 served ; and still more so when loaded with weights of 100, 
 500, or lOOOlbs. No friction, therefore, is requisite in ac- 
 counting for the resistance of these rollers to horizontal motion. 
 Nay, I submit, whether a resistance, arising from indentation 
 alone, would not prove to be " directly as the pressures and in- 
 versely as the diameters of the rollers ?" To me the subject 
 presents itself under three aspects : either the whole indenta- 
 
 E e 2 
 
146 
 
 tiori takes place on the rollers, when they are very soft and the 
 rulers very hard ; or the latter, when they are very soft and 
 the rollers very hard : or, which is most likely, this indenta- 
 tion takes place on both bodies at once ; so as to produce a 
 surface of contact, intermediate between the straight surface of 
 the rulers, and the cylindrical surface of the rollers. But in 
 either case, the place of resistance to horizontal motion, must 
 be out of the line of direction of the roller's centre of gravity : 
 and thus would the roller present more or less resistance, in- 
 dependently of every thing that can be called friction : and 
 which degree of resistance will continue to exist as long as the 
 place of contact is made to change on the rulers for thus to 
 change this place of contact is to renew this indentation ; which 
 process will elicit a resistance equal to what would be observed 
 were the roller (without indentation) forced up a plane, in- 
 clined to the horizon in the same angle as a line, drawn from 
 the centre of the roller to the extreme edge of the surface of 
 contact, makes with the perpendicular. 
 
 I cannot possibly enter at length into this subject, as it makes 
 no part of my engagement to the public : but I would observe 
 that this resistance is, a fortiori, something besides friction, 
 since greasing the surfaces 6( did not cause any sensible dimi- 
 nution of the friction;" whereas it made a difference of one 
 half! in some others of the experiments alluded to.* Were I 
 
 * See Dr. Gregory's Introduction to his Mechanics. Vol. II. 
 
147 
 
 asked the reason, I should answer, because friction had no- 
 thing to do with it ; and I would say further, that greasing or 
 oiling these surfaces would most likely increase, instead of di- 
 minishing, their resistance to horizontal motion : namely by 
 softening them, and making them more susceptible of change 
 of figure : which opinion gathers strength from another fact 
 adduced, viz: that "rollers of elm producd a friction (or re- 
 sistance) of about 5 - greater than those of lignum vitee :" but 
 why? because elm is relatively soft and lignum vitae hard the only 
 cause that appears sufficient to account for the facts observed. 
 
 I must now leave these remarks to persons having more means 
 and leisure than myself, to pursue the subject ; wishing only, 
 that useful truth may result from them : and that this unbelief 
 of mine "in several special kinds of friction," may at least be 
 found to have some reasonable ground to rest upon. 
 
 But I may be opposed in some of my statements by the fact, 
 that friction rollers, with centres, have been used with little 
 advantage ; and often laid aside. This I acknowledge ; and 
 go a step further. Friction is by no means of so much conse- 
 quence as it was once thought to be : and is not the source of 
 the greatest defalcations that occur in the use of power. Yet, 
 to get rid of it, in some cases, would be of considerable im- 
 portance ; and the subject deserves at least the attention of 
 every intelligent mechanician. 
 
148 
 
 Those who have used friction rollers, know that it is a thing 
 of great difficulty, to place their axes exactly parallel to that 
 which they are intended to support : and even, if rightly placed 
 at first, that a small degree of abrasion, greater on one pivot 
 than another, will soon destroy that parallelism ; and thus in- 
 troduce a growing friction, capable, at length, of rendering 
 the whole completely useless : for although the original friction 
 is lessened by being transferred to a slower-moving axis, yet 
 the latter still resists in some degree, say J of the whole ; (its 
 pivots being } of its whole diameter) so that the cohesion, or 
 something else, between the main shaft and the friction roller, 
 (thus resisted) must be sufficient to drag round the latter, 
 against about J of the original friction ; which in a word it 
 cannot do without some relative motion between those surfaces, 
 the friction roller lagging behind the main shaft, until its own 
 friction is overcome by another. And thus it is, that a friction 
 roller of this kind, does not make so many revolutions on its 
 pivots, as its diameter compared with that of the main shaft, 
 would imply ; for example, if the shaft were 4 inches in dia- 
 meter and the friction roller 8 inches, the latter would not 
 complete one revolution against two of the former. There 
 would thus remain a difference spent in real friction, in ad- 
 dition to that on the axis of the friction roller. Besides this, 
 we have the want of parallelism above mentioned ; which occa- 
 sions a rubbing, in the direction of the shafts, small indeed in 
 quantity, but for that reason very powerful in bringing on a 
 
149 
 
 change of form, and thereby hastening the common destruc- 
 tion. Both these accidents, therefore, make friction rollers, 
 in general, an unsatisfactory and perishable expedient : and it 
 is to make them less so, if not entirely to cure these evils, that 
 the two following articles are designed. 
 
 In fig. 6 of Plate 17, A B is an axis which it is desirable to 
 divest of its friction. To do this, as nearly as may be, I con- 
 nect with it two rings of hard metal C D, formed as truncated 
 cones ; and under the shaft, in the same vertical plane, I place 
 two smaller shafts E F, carrying on their tops, other two 
 cones, similar to the former. The summits of each pair of 
 cones meet of course in the points a b of the main shaft ; and, on 
 the principle of bevel geer, every contiguous part of the touching 
 cones moves with the same velocity: so that there is no sensible 
 rubbing between them for, 1st. the pivots c d, are hard and 
 pointed, and run on the hardest steps that can be obtained ; 
 and, 2ndly.the tendency of the cones u toward each other, is 
 repelled without friction by the cylinders ef, attached to them, 
 and which lean right and left against each other, turning with 
 the same velocity, without causing any friction, or any creep- 
 ing, between the two pairs of cones e C, and f D. All the 
 weight therefore, of the shaft A J5, (which of course is kept 
 in place in the other direction by proper side cheeks, &c.) rests 
 on the points of the vertical shafts E F, accompanied by no sen- 
 sible tendency of these points to quit the places assigned to 
 them. 
 
150 
 OF 
 
 A SECOND MACHINE, 
 
 To avoid or diminish Friction. 
 
 IN Plate 17, figs. 7 and 8, offer a mechanism different from 
 the preceding, though intended to produce a similar effect. 
 Referring to that cause of friction which consists in the want 
 of parallelism between a principal shaft and its friction rollers) 
 I here introduce a form for the latter, which admits of this 
 consideration being in a measure neglected. These friction 
 rollers are only portions of cylinders ; and they have no shafts. 
 They turn simply on a sharp edge, placed in a prismatic box 
 A B, in a well formed angle of which, they move to and fro, 
 without rubbing. When at rest, these axes Z> C D, (fig. 7 
 and 8) are drawn against the right hand side of the box, by 
 small weights E ; and the shaft is carried by one or the other 
 of them, according as they are, or are not, within reach of its 
 radius. Thus, in the present position of the shaft, (see fig. 7) 
 the second arc C supports it, the third having fallen behind the 
 first, so as not to be seen : and the first arc D being on the 
 point of taking up the load. In short there are six spaces, 
 either left or cut on the shaft, opposite the three arcs 2} C D. 
 1st. one space, of 3 of the circumference, left concentric with 
 the real centre of the shaft, opposite the first arc D, followed 
 by Y of a circumference cut an eighth of an inch lower. 2ndly 
 
151 
 
 another third of a circumference opposite the second arc C, begin- 
 ning where the first ends, and followed by ^ of a circumference 
 cut an eighth of an inch lower : and Srdly, another space of 
 3- in circumference, opposite the arc _D, followed by a similar 
 
 o 
 
 space of ^ cut an eighth of an inch lower. By these means the 
 shaft is never without a concentric bearing : and the better to 
 secure this property these arcs left, may be each of them more 
 than one third of a circumference in length, so as to avoid the 
 least drop at each change of roller ; and even to give the shaft 
 a support from two rollers at once, during a good part of its 
 revolution. 
 
 In using this mechanism, the vessel A JB, would be filled, 
 to a certain level, with oil or water, to prevent any blow from 
 the returning arcs which latter might be made to fall on a 
 lining of leather, to avoid still further all commotion: and thus, 
 even were these rollers not placed quite parallel to the shaft, 
 this imperfection would be corrected by the frequent renewal of 
 these movements, and the consequent absence of lateral fric- 
 tion between the arcs and the shaft. It may be observed that 
 either of the above methods of destroying friction is not con- 
 fined to the vertical direction : but may be so used as to receive 
 the pressure caused, in any direction, by the action of a wheel 
 or other agent. And with respect to the best use of each 
 method respectively, I would propose the former for light and 
 swift motions, and the latter for slow-going shafts, heavily 
 laden : it being well understood that the shafts must be kept 
 
 Ff 
 
152 
 
 in their places, in the less essential directions, by proper steps, 
 at the discretion of the person who employs these Machines. 
 
 Finally, I consider it as a matter of course, that all the 
 surfaces coming into contact in these operations, should be 
 as hard and impenetrable as possible. For if, by neglecting 
 this precaution, any change of form occurred, what is said 
 above could not be practically true : But these properties can be 
 reallized, with only those degrees of hardness that are often 
 employed in the mechanical world. Thus a die of hardened steel, 
 bears almost unimpaired, the strokes and pressure it suffers in 
 the coining-press. A chisel, stands thousands of blows and 
 cuts hard metal, without sensibly giving way. The knife- 
 edges which carry a heavy pendulum, suffer it to vibrate many 
 years without wearing out ; and the fulcrums of scale-beams, 
 bear enormous weights, for almost an indefinite period, with- 
 out any injurious effect. I request therefore, that these facts, 
 may be put into the scale, when my foregoing statements are 
 tried : whether as applied to these ant i- attrition machines, or 
 to my late patent wheel work, or both combined: for I foresee the 
 use of these friction rollers, cut into teeth on that principle, to 
 insure the proportionality of their respective motions. 
 
153 
 
 OF 
 
 AN EQUILIBRIUM COCK, 
 
 To prevent abrasion and leakage. 
 
 IN the common form of this useful instrument, no method 
 seems to have been devised for preventing the plug from being 
 pressed aside, by the weight of the liquid : which provision 
 nevertheless would have diminished the wear and tear of the 
 touching surfaces, and secured much longer the perfection of 
 the instrument. This property would be particularly desirable 
 in cocks which convey a fluid from a great height ; and still 
 more so in those used for containing steam or any other fluid 
 under a high pressure. I can hardly persuade myself that I 
 have stood so long alone in my ideas upon this subject ; but not 
 having seen any thing published on the subject, under a name 
 implying the above mentioned property, I venture to give this 
 as my invention which indeed it is, even should other persons 
 have pursued and embodied the same idea. 
 
 Fig. 9, 10 and 11 of Plate 17, represents one of the forms of 
 this equilibrium Cock. It consists of a square plug case or 
 chamber a b, with a hole c d bored transversely through it, ex- 
 actly across its centre : and to this chamber is fixed by the 
 flanches e f, the bifurcated water-passage g h, forming one 
 body at i. The plug of this instrument admits of various forms and 
 
 Ff2 
 
154 
 
 proportions; of which I have shewn two in the figures 9 and 11. 
 The first m n, receives the fluid through the two openings c d, 
 which correspond, in one position of the plug, with the double 
 water-passage before mentioned. And further, the plug itself 
 is bored lengthwise in its under end n, so as to form the spout of 
 the cock : or otherwise (see fig. 9) this spout is taken in a 
 double form from the outer surface of the plug at h a, so as to 
 present two streams, thus producing, I think, an instrument 
 of somewhat greater solidity. All that seems important is, that 
 whatever be the pressure of the fluid from without, it be made 
 equal on both sides of the plug, so as to occasion no friction be- 
 tween it and the chamber. The principle is indeed so effectual, 
 that one might distribute steam pressure of the greatest strength 
 or even gunpowder pressure, without much resistance to the 
 operator, and without injuring the mechanism by oft repeated 
 action. 
 
155 
 
 A MACHINE 
 
 To communicate and suspend Motion. 
 
 JlN Plate 19, figs. 3 and 4, shew this mechanism in two 
 directions. It is composed of two wheels C Z), cut (or cast) 
 into teeth of a peculiar kind, that both geer with one another, 
 and at the same time, include the chord or round strap A JS, 
 by which they are driven. These teeth can be better repre- 
 sentented by a figure than in words ; and will I suppose be 
 understood from figures 3 and 4 : They are divided, on the rim 
 of each wheel by a space too small to admit a tooth of the other 
 wheel : but then, every -other tooth is cut away in a sloping 
 direction on each side of the wheel, from the bottom of the 
 tooth to its top on the opposite side : so that while these teeth 
 are working in each other they offer two grooves, in the form 
 of a V, which coming together surround the chord and press it 
 in four points, either to drive the wheels by the cord, or to 
 pull the chord by the wheels, according to the use it may 
 be wished to make of this mechanism. In fig. 4 the cord is 
 seen at A B, passing among the teeth of the wheels ; and in 
 fig. 3 it is shewn at C, as a mere circle, in the centre of a 
 lozenge formed by the teeth whose points now geer together. 
 Fig. 5 is a sketch belonging to this subject, which shews some- 
 
156 
 
 thing of the manner of using this round strap as a mover : for 
 by carrying it (either in a horizontal or verticalplane) by a line 
 slightly curved, from one machine to another, it will drive 
 them all and give the means of stopping any one at pleasure. 
 Suppose then, ^4. B C D fig. 5, to be four machines placed 
 as above mentioned. If I wish to stop the machine _B, I 
 merely draw back the pressure wheel JE, and the cord ceases 
 to lay hold on the machine as shewn by the dotted line : but 
 when I want to set it on again, I do it by bringing back the 
 wheel E to its present position. And thus at a small expence, 
 I could geer a considerable factory, in a way which I think as 
 durable as it appears economical. The principal objection, 
 perhaps, is that this cord is liable to wear out soon, by such 
 incessant action ; but then the pressure on it needs not be 
 great ; and of friction properly speaking there is very little : 
 Besides which, the cords would be made of a peculiar texture, 
 perhaps of leather, sewed edge to edge and covered like a 
 whip, by one of the machines I shall bring forward hereafter. 
 
 It so happens that many of my Inventions are of a generic 
 nature, and thus apply to cases which, appearing different, 
 have nevertheless some common properties. The rule of con- 
 traries especially applies to many of them, of which this is an 
 example. It offers a good method of driving a boat through a tun- 
 nel, or other confined space, either by the force of steam or 
 any convenient power. To this end a rope laid along the side 
 
157 
 
 of such canal, and fixed at each end, or at several inter- 
 mediate points, might be led between a pair of wheels like 
 those above described ; which duly turned, would drive the 
 boat the distance required with the least possible expence of 
 power, and without the defect of agitating the water. But 
 I must not anticipate too much on my intended subjects. 
 
158 
 
 OF 
 
 A MACHINE 
 
 To set on, and suspend, rapid Motions. 
 
 I HIS Invention is under the protection of a Patent. It is 
 applied to the spindles of my spinning machinery called Eagles, 
 from their analogy to the machines named Throstles. It is in 
 my opinion an excellent machine ; as it secures a mathematical 
 equality of twist to any number of spindles from permitting the 
 use of geering to turn them, which could not have been done with- 
 out some means of stopping a single spindle. This mechanism 
 (see Plate 19 fig. 1 and 2) consists of a toothed pinion A sol- 
 dered to the box 13 C, (partly cut down in the figure to shew its 
 contents)and with it running loose on the lower part of the spin- 
 dle E D. In this box are placed two weights MN, like that M 
 fig. 2, which both together, fill the box loosely, and, rising 
 above it, are pinned at O P through the spindle. They are 
 moreover kept from quitting the latter by the ring shewn in 
 section at q q, which holds them loosely, yet prevents their 
 flying away or hurting any one. When now the spindle E D, 
 turns swiftly, the centrifugal force of the two weights M N, 
 projects them from the centre as far as possible ; and they lay 
 hold, by friction, of the cylindrical surface of the box J3 C, and 
 thus keep the revolutions of the spindle to the same number 
 of turns per minute, as the pinion A receives from the driv- 
 
159 
 
 ing wheel. But when the spindle is stopped and held by the 
 fly as usual, then the centrifugal force ceases to act, and the 
 box JB C does not wear out much, by its further revolutions. 
 And when as before, the spindle is again let loose, that fric- 
 tion which takes place on the bottom of the box sets the 
 spindle running again, when the centrifugal force comes to 
 its aid, so as to unite again the box and the spindle, thus re- 
 newing that valuable property of all spinning machinery, the 
 mathematical correctness of its movements. 
 
160 
 OF 
 
 A MACHINE 
 
 For forging. Screws, Beads, -c. 
 
 THE effect which this Machine is intended to produce, is 
 analogous to several culinary or officinal processes that might 
 named. It is called rolling : but not in the same sense in 
 which that word is used in manufactories, where rollers form 
 or' modify the body acted on. Here this body itself rolls be- 
 tween two surfaces moving different ways and receives from 
 them the desired impressions, and this idea I have extended to 
 screws; proposing to finish them on some metals and in some 
 dimensions ; and to rough them out in others. The Machine 
 is represented in figs. 6 and ^ of Plate 19, where fig. 7 shews 
 the faces of the arcs A J5 of fig. 6. By the form and connec- 
 tion of the arms A C and JB D, these arcs move opposite 
 ways : and since they are grooved obliquely as shewn in fig. 7> 
 if a prepared cylinder of soft metal a, be put between them, 
 and the handle C be sharply pressed into the position A E, 
 the cylinder a will be made to roll, and the grooves of fig. 7 be 
 impressed on it so as to meet and form the screw in question. 
 The only conditions are, that the arc B A be at least equal in 
 length to the circumference of the screw, when finished ; and 
 that the grooves (fig. 7) be rightly sloped, and have the form 
 intended to be given to the threads of that screw. It will occur 
 
161 
 
 of course, that the opening between the arcs at the point where 
 the blank cylinder is introduced, must be larger than the dis- 
 tance between the arcs by the whole depth of the threads to be 
 impressed : which therefore will begin to be formed at two op- 
 posite points the moment the screw a begins to roll. This 
 however, might and would be otherwise, if it were thought 
 best to form the arcs A JB spirally ; and let the deepening pro- 
 cess be gradual : in which latter case another consideration 
 would occur, namely ; that the grooves themselves (see fig. 7) 
 must diverge a little intead of being parallel, so as to permit 
 the screw to lengthen as the pressure should displace a part of the 
 metal. In all cases the upper surface of the grooves should be 
 milled so as to lay hold of the soft metal, and insure the rol- 
 ling motion : and should this material be hot -iron, the stroke 
 should be taken in an instant, and the machine be kept cool 
 by every proper method, in the intervals of working. 
 
 I need not add that this rolling process would be still easier 
 performed, if the impressions to be made were circular and not 
 oblique : such as beads, balls, &c. but these considerations I 
 leave to my readers. 
 
 G g 2 
 
162 
 OF 
 
 A DIFFERENTIAL STEEL-YARD, 
 
 To weigh vast Weights with short Levers. 
 
 A LATE 19, figs. 8 and 9, offers two representations of this 
 Machine one intended to shew its manner of acting, and the 
 other one of its practical forms. By means of the first, (fig. 8) 
 we may compare it with the common steel -yard ; and even 
 shew the latter as a part of the former. If a weight, or load 
 to he weighed M, were suspended to the arm A J5, and the 
 counter-weight W 9 placed at the point C, of the arm A C, we 
 should have a common steel-yard whose power would be as 5 
 to 1 : for the arm A B is just j- of the arm A C, and this is 
 the principle on which steel-yards are commonly made. But in- 
 stead of this, my steel-yard G E IB _D C H fig. 8, is now in- 
 finitely powerful : so much so indeed, as to be infinitely useless. 
 If millions of pounds were now to be suspended at P, they would 
 not raise the weight //^one tittle, for they hang entirely on the 
 point of suspension A. But although the Machine is now useless, 
 it can be altered in a moment and made both useful and com- 
 modious ; only I thought its principle would be the better un- 
 derstood from being thus shewn in excess. To make it a useful 
 and powerful Instrument, I only move the hanging bar D G, 
 to a b ; and the bar E B to c d, the lever b d being similar to 
 that E G. In this state of things, the whole load P is found 
 
163 
 
 at the point o of the lever B H, (for the lever-arms c o and d 
 e, and those e b, and a o are equal) and the power of this 
 steel-yard is as the line A. C to the line A o; that is as 20 to 1. 
 instead of being as 5 to 1 which it before was. But this is not 
 yet a powerful Machine ; being chiefly intended to shew the 
 principle on which it acts and to prove that however small 
 the distance A o, that distance, dividing the arm A C, gives 
 the real power of the steel-yard. And supposing now the arm 
 A C to be four feet in length, and the distance a Z), B c, and 
 A o, to be -ft of an inch, then the power of the weight w to 
 raise (or weigh) the load P is as 48 inches to -^ of an inch, or 
 as 480 to 1 : so that if the weight w were lOlbs. this steel-yard 
 would weigh 48001bs. or upwards of two tons ; and it is easy 
 to see that this power can be almost indefinitely extended. 
 
 Fig. 9 of this Plate shews a real steel -yard made on this 
 principle ; the power of which, under its present length, is as 
 40 to 1. In this Machine all the centres are fixed : and the 
 load is suspended on knife-edges, the distances of which from 
 each other and from the common centres are invariable as 
 they must be in all instruments of this nature. 
 
164 
 
 OF 
 A RETROGRAPH, 
 
 Or a Machine to write backwards, for Engravers. 
 
 A HIS Machine is exhibited in the two figures 10 and 11 of 
 Plate 19. It is composed of a straight ruler A B, having an 
 exactly dove-tailed mortice made along it, to receive the rol- 
 lers, (or slides) by means of which the parallelogram C D E 
 F slides up and down in this mortice. This parallelogram is 
 composed of four rulers C Z>, D E, E F, and F C, connected 
 by cannons or tubes fixed to every -other arm : and on which 
 the contiguous rulers turn very correctly. Through which 
 moreover, in two cases, F D the drawing pencils are intro- 
 duced, and under which other two cases, in C and E, the guide 
 rollers already mentioned are nicely fixed by the screws on 
 which they turn. This is seen by an elevation in fig. 10, 
 where p marks one of these rollers, and o q the end of the ruler 
 supposed fixed to the paper by proper blunt points, &c. At r is 
 seen one of the tubes which form the joints C and E : and r t, 
 are, one the writing pen, and one the retrographic style or 
 pencil. Fig. 11 is a plan of the whole Machine : where if the 
 hand guiding the pen D goes upward, the tracer F rises too. 
 But if the pen or hand D moves to the right, the tracer moves 
 to the left at the same moment. In a word this is to write 
 
165 
 
 backward in the sense of engravers, who thus write that their 
 letters may proceed forward after one impression. 
 
 If it were desirable to give the engraver the same facility he 
 has in the use of a pen, the tracer t, fig. 10, would be ter- 
 minated above as a hollow conical cup, into which he would in- 
 troduce a pointed style held as a pen. In this case the tracer 
 t, would be made as short or low as possible, to bring the style 
 so much the nearer to the paper ; and thus to prevent all ano- 
 malous movements. 
 
166 
 
 OF 
 
 AN ETE MACHINE, 
 
 Or Machine for making the Eyes of Hooks and Eyes. 
 
 IF it were enquired why this Machine is offered to the public 
 without the Hook Machine ; the answer would he, this only 
 is finished: and it is wished to present nothing here that admits 
 even a doubt of its utility. The drawings given in Plate 20, figs. 
 1 2 and 3, are more intended to be useful in the construction 
 of this Machine than complete in appearance : so that nothing 
 has been done by way of shading, but what it was thought 
 would the better distinguish the parts from each other, and fa- 
 cilitate their assemblage in one effective Machine. The Ma- 
 chine consists first of a slide A B, (worked by a lever-handle, a 
 crank, or any proper first motion.) It glides between two 
 cheeks C D, (see the end view in fig. 1) connected with the 
 several parts about to be mentioned. This slide is marked A 7J 
 in all the three figures. It carries (by means of the screws a b, 
 coming through the slits c d, in the main Plate E F) a plate g } 
 the chief use of which is to support a tumbler e, whose use is 
 to throw the eye, when made, from the machinery : which 
 tumbler is kept to its work by the spring i, as will be further ex- 
 plained presently. This slide itself has a peculiar form at the end 
 B, (fig. 2) which is shewn by dotted lines at c d in fig. 1. It 
 is a slit, with the corners rounded off for the purpose of working 
 
the springs now to be described. These springs m n, (see fig. 
 2) are fixed to a cock, itself screwed behind the main plate : 
 and they come through the latter to the left -hand -ends of the 
 small curved mortices seen (with the springs) at m n fig. 1. 
 The slide ^4. B then, with its forked end shewn by the dotted 
 lines at c d, is destined to take the springs m n and carry them 
 to r * , where they are now seen surrounded by the eye almost 
 formed : for in this motion these springs take the wire (shewn 
 by the lines dotted across the Machine and previously cut by the 
 sheers u) and meeting with the obstacles t v, being the thicker 
 parts of the clams t v w, they bend it into the form r s when 
 the screws a b lay hold of the sloping ends of the clams c t w 
 v d, and squeeze them together ; by which operation the hooks 
 t v finish the eye, by rolling its two ends round the springs m n 
 now in the position r s. Where note, that the slit c d of the 
 slide A 7? is so formed as, when it has carried these springs m. n 
 to r s, to slide forward without doing any thing more to them, 
 while closing the clams. It performs, however, some other 
 less important operations, to which it is now necessary to 
 allude : among other things this slide works the sheers u that 
 cut the wire, and that, by means of the doubly wedged hook 
 x, which goes back with the plate G, doing nothing : but 
 which by the action of its springs fixed at , falls under the 
 sloping end of the sheers u; and, when the slide, by the screw 
 by carries it to the right hand, raises the end x of the sheers u, 
 and cuts the wire near v, to prepare it for the operations 
 already described. The party in the two figs. 1 and 2, is the 
 
 nh 
 
168 
 
 other cheek of the sheers fixed by screws to the main plate, 
 and covered by a small plate z, in which a nick is cut to form 
 a passage for the wire, and present it to the sheers, that they 
 may cut it to the proper length, after having directed it right 
 across the springs r *, then placed by their elasticity at 
 m n. It hardly need be added that a stop is placed at o, 
 to determine the length of the wire so as to form the eye 
 complete, and not to admit more wire than is sufficient ; all 
 which is regulated between the sheers and the stop, by proper 
 adjusting screws, which it is very easy to suppose or supply. 
 
 . 
 
 Fig. 3 is intended chiefly to shew the mechanism by which 
 
 the eye, when finished, is thrown off the pin round which it is 
 
 bent by the springs m n. It consists of a tumbler e, placed in 
 
 a mortice in the end of the plate g, and kept to a given position 
 
 by the pressure of the spring i. When the slide dL B is carried 
 
 forward, toward J, to perform the operations already noticed, 
 
 this tumbler e, gives, way to the angle G of the doffing lever m G, 
 
 (this lever being shewn also between c m & d n in fig. 1) and rides 
 
 towards m without producing any effect either on the plate G 
 
 or the lever m G : but when it has once passed the said angle 
 
 G, it cannot go again toward F without depressing smartly 
 
 the end G of that lever, and thereby raising the end m, thus 
 
 starting the eye from the stud m, round which it had been bent 
 
 by the processes above described. 
 
 At the right of fig. 1 near F, is an object, the use of which 
 
169 
 
 is too evident to need description. It is a double spring for the 
 purpose of keeping the hoo ks c t w v d pressed against the pins, 
 near t v, which determine the position of the said hooks ; and the 
 degree of bend first given to the wire by passing the points t v. 
 
 There are some less important parts and operations left un- 
 drawn, in order to prevent confusion in the figures : but they 
 are such as would strike any person having the above under 
 his eye. In a word I have done what I thought best to aid the 
 construction of this Instrument : which is represented at two 
 thirds of its natural size but whose dimensions, of course, 
 would vary with that of the objects to be produced by it. 
 
170 
 
 OF 
 
 A VENTILATOR, 
 
 Rotatory yet by pressure. 
 
 BY this title I wish to distinguish this Ventilator from all such 
 as act by the mere centrifugal force of the air : and to make this 
 distinction the more palpable, I would add that this Machine 
 acts like a pump, that is by means of a space alternately con- 
 tracted and expanded, into which the air enters, and from which 
 it is expelled by force as water is from a pump. The means are 
 the following : A B (fig. 4 of Plate 20) is a hollow cylinder, 
 of a diameter proportioned to the effect wanted to be pro- 
 uced. C is a cylinder closed at both ends, which fills that just 
 mentioned as far as the length goes, excepting a play of 
 about $ of an inch. This interior cylinder revolves in the 
 former ; but not on its own centre. It revolves on an axis E ec- 
 centric to itself, but exactly concentric with the outer cylinder 
 A B. The centre therefore, of the inner cylinder C, describes 
 a circle within the outer one, which is always parallel to its 
 circumference. On the axis of motion of this cylinder C, and 
 outside of that A B, are fixed two cranks E F fig. 5, which 
 exactly reach from its centre of motion to its centre of figure : 
 so that whatever circle the latter describes in the large cylin- 
 der, the former describe the same line without it. And hence 
 any slide or valve D, driven by these cranks, will always touch, 
 
171 
 
 or be equally near, the circumference of that interior cylinder 
 C. The valve D then, worked by the bars G from without, 
 forms a constant separation between the right and left hand 
 parts of the lunular space left between the fixed and moveable 
 cylinders ; and if the latter turns from C by B to Z>, the right 
 hand space C B G is the plenum, and the left hand space C 
 A D is the vacuum of this Instrument ; or in other words the air 
 will flow m ? through the passage H 9 and flow out through the 
 passage /: and by a contrary motion of C, it would do the 
 contrary but I prefer the first process because any pressure 
 within the valve D is not liable, then, to press the valve upon 
 the drum C, and produce contact and friction ; which in the 
 second case it might do. Suffice it to add, that the quantity of 
 air displaced at each revolution of C round its centre of motion, 
 is the difference between the area of the drum Cand that of the 
 cylinder A B : and that its quantity at each part of the revo- 
 lution is proportionate to the curvilinear triangle G B 9 mul- 
 tiplied by the length of either cylinder. 
 
 In the prospectus, this Machine was said to be good as "a gas 
 meter," which I still think it is. For such a purpose however, 
 friction and eccentricity of weight should be obviated, by plac- 
 ing the axis E, in a perpendicular position : when I doubt not 
 it would measure flowing gas better than many of the machines 
 that have been proposed for that purpose. 
 
172 
 OF 
 
 A COMBINATION OF WHEELS 
 
 To raise Water. 
 
 JL HIS mode of raising water in its simplicity, is I think called 
 the Persian wheel. The b.uckets hang upon centres, dip in the 
 under water, fill themselves there, and by meeting an obstacle 
 above which turns the buckets aside, they empty themselves into 
 the upper back, from which the water is conveyed to the 
 general reservoir prepared for it. This present Machine is 
 such an extension of the above principle as to make it appli- 
 cable to considerable degrees of elevation, and to many situa- 
 tions where a single wheel would be of no service. Having 
 observed that in every train of wheels, the circumferences of 
 any two wheels, have motions towards each other, as well as 
 from each other ; I perceived that, in a vertical train, this 
 circumstance might be laid hold of to compose a machine for 
 raising water. Be therefore, (Plate 21, fig. 1) A B C D four of 
 a set of wheels thus intended : on the left of the lowest wheel the 
 buckets move upward, as indicated by the arrow ; while those 
 at jB move downward, coming thus to meet the former. The 
 buckets A are full, and those B are empty; and as the latter, 
 by the motions of the equal toothed wheels on which they are 
 hung will infallibly meet the former, and even plunge into them 
 at / K and JL, it is only to put a clack of leather or a valve, in 
 
173 
 
 the bottom of all the buckets, and we have a machine that will 
 raise water to the top -most wheel, be it ever so high, and there 
 the water will be poured out into the vessel M 9 as in the common 
 Persian wheel above alluded to. On this principle the first 
 change of buckets will take place at /; where the lower bucket 
 belonging to the wheel B G will take the water from the upper 
 bucket of the wheel AH; when the bucket / will go down, 
 nearly empty, by PI and fill itself again in the under water ; 
 But the bucket of the wheel JB G having now got the water, 
 will rise by G to K, where another bucket belonging to the 
 wheel C-Fwill come empty, and plunging itself into that, take 
 its water and go upward by way of C to L, where a similar 
 change will take place and the water from L will rise by E to 
 M 9 into which vessel it will be poured by the canting of the 
 bucket as seen in the figure. Thus it appears that any number 
 of toothed wheels geering together, surrounded with buckets 
 valved at bottom, and receiving power from any one of their 
 number, will raise simply and effectually a quantity of water 
 not small in proportion to the power employed, and by means 
 that promise great durability to the Machine. 
 
174 
 OF 
 
 AN ECCENTRIC BAR PRESS, 
 
 For clearing wetted goods of Water. 
 
 A HIS press (see Plate 21, fig. 2) is indefinitely powerful. It 
 was invented for the use of my late beloved brother, then con- 
 tractor with government for cleansing the sea bedding. It is 
 composed of a centre piece A, strongly fixed to a post in the 
 ground, the bars A B A C being suspended above it, so as to 
 remain horizontally moveable, while describing ^ of a revo- 
 lution round the general centre A. The blankets (or other goods) 
 are put into the space s, (on a net nailed under the bars) 
 while in the position A B ; and the whole is then thrown with 
 force towards B C ; the length A C being so calculated as to 
 cease pressing at the desired moment : for such is the power of 
 this Machine, even without this projectile force, that were the 
 stress not moderated, nothing could remain whole under its ope- 
 ration. It is clear however, that, when this operation begins 
 at s, the relative motion of the jaws s and B is assignable, and 
 even visible, as shewn by the dotted circles ; but as the whole 
 approaches toward J3 C that relative motion becomes insen- 
 sible, the circles parallel, and consequently the power infinite : 
 which is all I shall say on the theory of this Machine. 
 
1/5 
 OF 
 
 A COLOUR MILL, 
 
 For Calico Printers. 
 
 THIS Machine is delineated in fig. 3 of Plate 21. It has 
 several properties which I think important in the process of 
 grinding colours, either in a wet state or a dry. It consists of 
 a frame A B, which has a hollow centre, through which the 
 axis of the bevel wheel C D is brought in such manner as 
 to geer with the bevel pinion P, in whatever position the 
 frame A B may be placed. The axis of the pinion P carries a 
 vessel of which E F G is a section, and in which rolls a well 
 turned and heavy ball If, upon the colour to be ground : which 
 it crushes in the line of direction of its centre, and to a greater 
 or lesser width according to the diameter of the ball, as com- 
 pared with the section of the groove E G, in which it rolls. 
 Now as the motion of the vessel E G F, is oblique to the per- 
 pendicular, the contact between it and the ball does not take 
 place in any great circle of the latter : but is constantly varying 
 by a twist in its motion dependent upon the angle of the vessel's 
 inclination to the horizon. From hence arises the impossibility 
 of any colour remaining on the ball unground : and in order 
 likewise, that none may remain uncrushed in any part of 
 the vessel E F G, the frame A B gives it constantly new 
 positions, one of which is represented by the dotted lines / K : 
 
 
 
 1 1 
 
176 
 
 where it is seen that the hall bears on a different line of the ves- 
 sel's bottom than it did before. This also adds still greater change 
 of action to the ball itself, and occasions (taking both these 
 properties together) an unbounded variety of effect, which neces- 
 sarily brings every particle of colour under the ball by the mere 
 continuance of motion : and thus grinds it all without any care 
 on the part of the attendants. It may be added, that this vi- 
 brating motion of the frame A B, is easily made to result from 
 an eccentric stud and proper connecting rods behind the frame ; 
 all which is too easy to require further description. 
 
177 
 
 OF 
 
 A DYNAMOMETER, 
 
 Or a second Machine to measure power resistance in motion. 
 
 In Plate 21 fig. 4, there is a representation of this Instrument. 
 It is composed of a frame A B, containing a strong shaft CD, 
 on which are placed the three following objects. First, a fixed 
 pulley E, working by a strap, the Machine whose resistance is 
 to be measured. 2ndly, a loose pulley jP, receiving the power 
 from the mover whatever it be. And Srdly, a barrel G, which 
 is the acting pulley, when the strap is put on it from F in the 
 common method. But this barrel G acts by means of a barrel- 
 spring within it, which is hooked by one end to the boss of the 
 shaft, and the other to the rim of the barrel, as is usual for 
 barrel -springs in general. Now the power produces the desired 
 motion by coiling this spring to the necessary degree : and to 
 make that degree visible, there is fixed to this barrel G a spiral 
 5, which as the spring bends, drives outward the stud t, and 
 with it the finger v, which, pointing to the graduated scale, 
 shews at once the number of pounds with which the spring acts 
 on the shaft C D to turn it. By these means the stress on the 
 straps and on the Machine turned is known ; of which also the 
 velocity is easily determined by counting the number of revo- 
 lutions performed by either of the pulleys E F G, which 
 are alike in diameter- 
 
178 
 
 In ending the first part of this work, I gave my readers room 
 to expect this part " within three months/' and am happy now 
 to fulfil that engagement. Although these pages contain fewer 
 errors than the former an apology is due for those that have 
 crept in : to which I add the promise that every thing shall be 
 done to lessen them further in the future parts, and wholly to 
 correct them before the work closes. 
 
 Page 100, line 2, for " :", read :: ; 
 ,, 126, ,, 4, ,, "on its surface" 
 
 read at its pitch line. 
 126, ,,17, " its height/ 
 
 g," read the length required. 
 129, !, "2," read 4, 
 20, " imperfect," 
 
 read homely. 
 
 Page 144, line 7, take away <( alone" 
 }> 8, for " usually" read 
 
 chiefly. 
 146, 23, for the friction," 
 
 read iti 
 147, ,, I, for "nothing," read 
 
 little or nothing. 
 
 In fig. 7 of Plate 19, slope the groove 
 of both faces the same way. 
 
 A few words seem wanting to complete the description of 
 the Cutting Engine above given. They relate principally to 
 the cutter-frame and cutters. Although, with a view to 
 celerity, I have shewn the cutter out of the frame (fig. 4) yet 
 a common frame, carrying the arbor on points, may be used 
 with propriety ; and would often be an eligible substitute for 
 the frame above described. In cutting bevel wheels however, 
 either on this Machine or that to be described, there is a form 
 of the cutter frame which leaves less freedom of choice, as the 
 cutter itself must have a peculiar form and position. To return 
 to the cutter for spur wheels, their form (or section) depends 
 on the degree of finish which the wheels require. For rough 
 
179 
 
 work they may be cylindrical on the face, the sides being under 
 cut) so as to leave them thickest at the circumference 
 whence a certain coarseness of cut ensues, but without any 
 injury to the spiral form. But, generally speaking, the cut- 
 ters are best, when made a little tapering towards the edge, 
 and toothed on both sides as well as on the circumference. 
 The teeth should be tolerably fine, but not very so, unless 
 great smoothness of surface were required : and we have seen 
 above that, in this System, great smoothness is very seldom 
 necessary, provided the obliquities be correct. I may add, that 
 those cutters used on common engines, whose great rapidity 
 compensates for the small number of their teeth, would not 
 answer here, on account of the twisting motion in the wheel. 
 But nothing prevents using cutters, so formed on the sides, as 
 to round off the teeth in the act of cutting-^-only the cutter must 
 be so thin as that its thickness, added to the aforesaid twist, 
 may not make the spaces too wide. A little observation will 
 render these things familiar to an attentive observer : nor shall 
 this work conclude before all that I have gathered from long 
 observation on this subject, be fully known to my readers. 
 
 J. W. 
 
 5, Bedford-street^ Chorlton Row, 
 20th. November, 1822. 
 
PART THIRD. 
 
 A NEW CENTURY OF 
 
 Sfnbentt'oti.s. 
 
183 
 
 J.T has been observed and regretted by a well-known writer, that 
 " a periodical work resembles a public carriage which must de- 
 part at the usual hour, whether full or empty;" and having 
 undertaken to deliver this work at stated periods, I have found 
 myself in a situation not unsimilar : the consequence of which 
 has been a too cursory view of some of the subjects. I feel 
 however, that this is not a sufficient apology for any essential 
 defect : nor would it be more so to say that, although verging 
 to old age, I am still a young auldior. Yet I may claim the 
 privilege of supplying, in the latter parts of the work, what 
 is most deficient in the former ; and thus of proving that I do 
 not intentionally neglect any thing that might make it prac- 
 tically useful. 
 
 With these views I commence this third part: intending first to 
 continue the description of the Cutting Engine given at page 
 121, and here applied to JBevil Wheels ; and then to re -con- 
 sider, shortly, one or two other objects, that were too rapidly 
 passed over in their proper places. 
 
 Plate 22, repeats at fig. 1, the first figure of Plate 15 ; by 
 way of shewing the additions required to extend this method 
 of cutting teeth, to Bevil Wheels. These additions are first, 
 a disk n n, concentrically fixed to the main axis A B of the 
 engine. And, second, an inclined plane o, of variable obli- 
 
 K2 
 
184 
 
 quity, connected by a joint with the forked sliding bar p q, by 
 which the plane o is put in contact with the disk, at whatever 
 distance the cutter-stand ef may be from the common centre, 
 which distance depends, of course, on the diameter of the 
 wheel to be cut ; and to secure which is the oftice of the fixing 
 screw r, in the figure. 
 
 It is now evident that for the disk n n, and the shaft A J5 to 
 rise, the slide p q and the cutter-stand e f must recede : and 
 this more or less according to the degree of obliquity of the in- 
 clined plane o, that is according to the slope of the bottom of 
 the teeth in the wheel w : see the dotted line w p. 
 
 A circumstance presents itself, that should be here explained : 
 when the bevil of the wheel w, or the cone of which the wheel 
 is a part, is very obtuse, the cutter -stand e f, can not be 
 driven back by the action of the disk n n on the plane 0, with- 
 out too great a stress being applied from below, to the axis 
 A B. (See the apparatus I M O N, Plate 16, fig. 2.) In 
 this case therefore, the handle R is not used : but a weight is 
 suspended to the end .2V of the lever M N, sufficient to give 
 the whole System A B, a tendency to rise ; and the operator 
 now acts on the screw g*, so as to draw back the plane o; 
 by which motion the disk m n with it's axis A 13 is suffered to 
 move upward, and the wheel is cut, as desired. But on the 
 other hand when the wheels are portions of acute cones, 
 
185 
 
 they are cut by means of the aforesaid handle ; by which the 
 plane o and the cutter -stand are forced backward as before 
 intimated. 
 
 We proceed now to describe the perpendicular part of the 
 cutter stand ef; which is made double, as shewn at i k in fig. 4 of 
 Plate 15 ; and is also perforated at various heights to receive the 
 bolt which forms the centre of motion of the arm m u, the lat- 
 ter having a cylindrical boss u, fitted into the fork of the stand 
 ef, and so graduated as to determine the angle of it's obliquity 
 to the horizon, or it's parallelism to the dotted line w p, which 
 indicates the slope of the bottom of the teeth on the wheel. 
 Finally, the cutter-frame oc is fastened to this arm at right 
 angles to it, and thus forms a right angle (or nearly so) with 
 the surface of the wheel : and is, moreover, directed to the 
 centre, produced, of the shaft A B. This latter fact is strictly 
 true, only when the teeth required are of so common a kind as 
 not to require greater exactness : for in theory the sides of the 
 cutter (supposed cylindrical) must alternately direct to that 
 centre namely, that side which is actually cutting : so that 
 a provision must be made to shift the cutter spindle sideways, 
 a distance equal to it's diameter; this being no more than 
 what is necessary in every system of wheel cutting. 
 
 We may also consider here, the form of the cutter itself, 
 v, fig. 1. It is slightly conical, (more or less so according to 
 it's use) and of no greater diameter than the smallest width of 
 
186 
 
 the spaces between the teeth of the wheel. A common disk- 
 like cutter would not produce perfect, nor even tolerable teeth 
 on a bevil wheel. The reason of this will appear by consider- 
 ing that a spiral line, either on a cone or it's base, turns more 
 the further it is from the centre, and less the nearer it comes 
 to it. So that aflat cutter placed at any angle, is parallel to 
 the curve at one place only ; whence the propriety of using a 
 cutter of the kind represented in this figure. It is however 
 true, that the first opening of the spaces may be made with 
 a common cutter ; but it should be very thin comparatively 
 with the spaces required : and it's cut would serve only as a 
 sketch of such space, serving principally to permit the metal to 
 escape while finishing the teeth with the cutter just described. 
 
 I proceed now to the examination of the plates, and the 
 manner of adapting their length to the process of cutting spiral 
 teeth on bevil wheels. But before entering on this subject, I 
 would explain a kind of inadvertency into which I fell at the 
 close of my former description of this Engine (see page 129). 
 In my zeal to be candid in stating the properties of my Ma- 
 chines, I have suffered it to appear that I thought this an " im- 
 perfect" one i an expression which, although modified among 
 the errata, may still cause it to be looked upon as radically de- 
 fective ; than which nothing could be further from the idea I 
 wished to convey. I intended merely to express the want of 
 absolute connection between the two movements of the shaft 
 the rotatory and longitudinal motions. I meant that the process 
 
187 
 
 by this Machine was not theoretically certain, because depen- 
 dent on the action of a weight (Plate 16, fig. 1 and 2) and an 
 unforced obedience to the direction of the plates. But this small 
 remove from rigourous principle is in my opinon much over- 
 ballanced by the facility of cutting good wheels of all diameters, 
 by the sole change of a morsel of tin, which leaves untouched 
 every other part of the Engine. 
 
 Entering then on this branch of the subject, I first observe 
 that if we chuse for the teeth an inclination of 15 degrees (in 
 imitation of the cylindrical wheels) it can only be for one point 
 of such wheels as observed above. This point therefore I 
 have placed at r in the middle of the face. And supposing now 
 that at this point the wheel O were 4 inches in diameter and 
 the wheel S two inches, these plates would be found as before 
 by these analogies : 
 
 (1) wr, or 2 inches : 11 inches (rad. of plate rim) : : 26.8 : 
 
 294.8 . , 
 
 = 1/4.4 plate required. 
 
 (2) vr, or 1 inch : 11 inches (rad. of plate rim) : : 26.8 : 
 ~i = 294.8 2d. plate required. 
 
 But it is plain that the conical face, b C, (common to both 
 wheels) is broader than the supposed cylindrical ones b e and 
 b d : and therefore that the above plates must be made longer 
 (to furnish the said obliquity) in the following proportions, 
 namely : for the wheel O in the ratio of b e to b C ; and for the 
 wheel s in that of b d to b C : that is, these plates should be 
 
168 
 
 lengthened as the tabular cosines of the angles B A C and 
 D A C to radius (for b e : b C : A : A C; and b d : b C : 
 A D : A CJ Thus then, 
 
 (1) Cos. 63 27' : radius : : 147-4 (present plate) : required 
 plate a?, ; = e^6^7 7 5 an d 
 
 (2) Cos. 2633' : radius : : 294.8 (present plate) : required 
 
 1 4- 294.8 r 
 
 plate y, - - c 
 
 Now, by the tables, cosine 2633 / 894, and cosine 63 27 
 (it's complement) 447, when radius is 1000 : whence di- 
 viding the two equations by r, and substituting these values of 
 cosines 6327 and 2633 we shall find the two quantities x 
 and y, equal. Whence it appears that for. every pair of bevil 
 wheels, whose shafts lie at right angles, the same plate serves 
 for both wheels : only turning it once to the right, and once 
 to the left hand on the plate rim. 
 
 And if now we measure on a scale of equal parts, the line 
 A r and call it 100, we shall find the line w r (near enough 
 for practice) to be 90, and the line v r to be 45, and these 
 numbers respectively, put for rad. for cos. 2633-, and for cos. 
 6327, will make the first equation x - 
 
 or x = 327.55 and y 327.55, &c. confirming the above de- 
 duction that the same plate serves for both wheels ; and giving, 
 withal, the length of the plate required. 
 
 In performing this operation by actual measurement of the 
 lines, I have had in view to trace a path for those of my read- 
 
189 
 
 ers who may not have the tables, or may be unaccustomed to 
 use them. The process, generally, is to take the diameter of any 
 bevil wheel O fig .4, in the middle of it's face ; and supposing it 
 a spur wheel, to find it's plate by the method above given : and 
 then to multiply the length of that plate by the line A r and di- 
 vide the product by the line A w 9 both measured on the same 
 scale of equal parts. 
 
 It may be well to observe, likewise, that the same method 
 of finding the plates, applies to bevil wheels of every descrip- 
 tion or angle : but that it does not give equal plates for every 
 pair, except in the above case of wheels placed at right angles 
 to each other. 
 
 I would just remark that by the figure near J9, is shewn a 
 section of the Machine on which I centre the wheels to be cut 
 on this Engine. It is an inverted cup s t, into which the arbor 
 is screwed in a true position ; and this cup is fixed on the top 
 of the shaft A B, by the three pressure screws near s t, which 
 enter a triangular neck made round the shaft, against the 
 upper slope of which, the screws press so as to draw the cup 
 downward in the act of centering it. This I say is my present 
 method ; but it is in a measure accidental, the shaft not having 
 been perforated to receive arbors of the usual kind. Mine, 
 however, have their utility in the ease with which they are 
 varied in size, and changed on the Machine : but on their 
 
190 
 
 comparative usefulness I give no opinion. The other is the 
 most solid method. 
 
 In the description of my differential Steel -yard, (see page 163) 
 I stated that the load P was wholly collected in the point o ; 
 and that dividing the line A C by the line A o, the power of 
 the Machine was known. But I should have shewn that this 
 line (A. oj is equal to one half the difference between the amis 
 A D and A E. To do this, here, (see Plate 23, fig. 4) I 
 take the Machine in the state of infinite power, before men- 
 tioned ; and observe, that in moving the point of suspension 
 from o towards A, I at once lengthen the arm A E, and 
 shorten the arm AD: by which process, (supposing each arm 
 to have been called J that which I lengthen by any quantity 
 d becomes a + d, and that which I shorten by the same 
 quantity becomes a d 9 and the difference of these quantities, 
 is 2d : so that the line A o is in reality one half the difference 
 between the two arms A D and A E as was required to be 
 shewn. 
 
 But we may go a step further : The two arms of the equi- 
 brachial lever xy may likewise be made unequal : and the line s a 
 be subdivided in any ratio : which division will augment still 
 more the power of this Machine. If for example, we hang the 
 load on the point v, halfway between a and s, that power will 
 be doubled ; for the line c v (representing the space moved 
 
191 
 
 through by the load in this case) is only one half of that w s, or 
 o q, and might be still less at pleasure. Thus the whole power 
 of the Machine is now found by dividing the length of the long 
 arm, beyond Z), by the line a v, instead of the former line 
 A o, or_ dividing the motion of it's extremity upward, by the 
 line c v, the motion downward, of the load P. 
 
 It has been further suggested, that the description of my 
 excentric Bar Press was not sufficiently explicit. I have there- 
 fore added the figure 2 of Plate 22, to assist in elucidating that 
 description. I had, perhaps made an undue use of the principle of 
 virtual velocities by saying, too concisely, (page 1/4) that "as the 
 " whole approaches toward B C, the relative motion (of the 
 " cheeks s and J5) becomes insensible, the circles parallel, and 
 " consequently, the power infinite." It is however vulgarly 
 said that power cannot be gained without losing time which 
 implies that if time is lost, power will be gained : and the prin- 
 ciple of virtual velocities says the same thing, though in more 
 appropriate terms that if a small movement be given to a 
 system of bodies actually counterpoising each other, the quan- 
 tity of motion with which one body ascends, and the other des- 
 cends perpendicularly, will be equal : so that, as remarked in 
 page 50, by " whatever means a slow motion is obtained, de- 
 pendent on that of a moving force, the power is great in the 
 same proportion. Now, in the eccentric Bar Press, (see 
 fig. 2) this is so in an eminent degree : for when the bars 
 are in the position A B, the distance of the cheeks is equal to 
 
192 
 
 S s ; and they must move, circularly, as far as A f, to bring 
 them closer to each other by the quantity s a: dividing there- 
 fore, the distance B g by the line s a, we find (near enough 
 for practice) the power of the Machine within the limits A g B. 
 It is nearly as 10 to 1. In like manner this power at A e g, is 
 equal to the arc e g divided by the line/* b ; and at A I n to the 
 arc / n divided by the line d k, namely by the difference of the 
 lines k I and m n. From the above it appears that the nearing 
 motion of the cheeks of the press, becomes slower and slower 
 as the bars A and C come nearer to the point C : insomuch 
 that the difference between the lines m n and o p is nearly im- 
 p"erceptible, and that between the lines o p and C q entirely so. 
 But according to the above process, the distance p C should be 
 divided by this imperceptible line, to find the power of the press 
 at the point C ; which therefore is immense. Another proof 
 of this may be drawn from the supposition (see fig. 3) that 
 the small lever a d is turned round the centre o by a bar o 
 C fixed to it, and of equal length with the line A C fig. 2. Fig. 
 3 shews that the lines or bars C d, and a C are moved endwise 
 by the circular action of the points a and d ; and therefore (by 
 statics) their motion is the same as though caused by the per- 
 pendiculars b o and o c let down from the centre o, on each of 
 them. Hence the power of this Machine is found by dividing 
 the distance o C by the sum of the lines b o and o c ; which sum 
 (when these lines vanish by the union of the bars over the cen- 
 trt ) becomes infinitely small : the quotient of which division 
 therefore is infinitely great as was to be shewn. 
 
193 
 
 OF 
 
 A PUNCH MACHINE, 
 
 For Engravers to Calico Printers. 
 
 J. HE usual method of making Punches for engraving Copper 
 Cylinders, (otherwise than by the milling system) is to cut 
 the desired pattern on a die, and then to transfer that pattern 
 by blows or pressure to the punch, from which it is again 
 transferred to the cylinder. My Machine in this operation, 
 unites motion to the needful pressure ; and thus renders the 
 result more easy and complete. This effect I could the better 
 ensure, because the surfaces of my punches are essentially con- 
 vex, or rather cylindrical ; as will appear when my engraving 
 Machine comes to be described. Their convexity however, 
 can be diminished at pleasure w r hence this Machine is ca- 
 pable of offering useful assistance to a maker of flat punches. 
 
 In Plate 23, A B fig. 1 and 2, is the body of the Machine, 
 with the vibrating bar C D laid upon it ; reposing especially 
 on the correct and level parts of the body at a b ; this bar con- 
 tains the die c, with which it vibrates between the cheeks 
 J$ 7?, as impelled by the screws E F, it's centre of motion 
 being the pin P, duly supported by the strong shoulder A. In 
 a line with the bar C Z>, is placed a second vibrator G, con- 
 taining the steel d, that is to become a punch, already rounded 
 
194 
 
 into the cylindrical shape it must have when finished. This 
 vibrator has it's centre of motion at e fig. 1, and it need not be 
 added that the curvature of the punch depends on it's distance 
 e d from that centre : for the centre of the long bar C D is so 
 distant as to have little influence on it's formation. Further, 
 the cap or bridge HI, which furnishes a centre for the smaller 
 vibrator G, can be brought forward to any useful position by 
 the nuts K L : that cap sliding horizontally between the 
 cheeks M N as directed by the small arms m n. This motion, 
 then, taken from the nuts K L, serves to impress the work of 
 the die on the steel prepared for the punch ; and this being done 
 to a first degree, both the handles O Q, are laid hold of : and 
 by turning the screws the same way one of them goes forward 
 and the other recedes, until the punch and die have been in 
 contact over half their surface. At this moment both screws 
 are turned backward, and the motions of the two vibrators 
 reversed : by the repetition of which alternate motions ac- 
 companied by the needful pressure, the whole pattern is trans- 
 ferred from the die to the punch when the latter is taken out 
 of the Machine, andjiled up in the usual method. 
 
 It should be observed, that the smaller vibrator G can be 
 displaced with ease when the nuts K L are withdrawn : and 
 this should be frequently done to examine the progress of the 
 impression. Nor is there any difficulty in re-entering the figures. 
 In a word, the perfection of this process depends more on 
 
195 
 
 much motion than on violent pressure : whence this facility 
 of re-entering is a desirable property. This Machine is us- 
 ually laid on a bench or tressel, with a long mortice in it, 
 into which the feather x of this Machine enters so as to be 
 firmly fixed. 
 
196 
 
 OF 
 
 A DIFFERENTIAL PUNCH MACHINE 
 
 For Engravers. 
 
 JL WAS the rather induced to attend a second time to the 
 differential Steel-yard, because I had it in contemplation to 
 apply that principle to the present purpose ; since, to make flat 
 punches, is to some engravers a more desirable thing than to 
 make cylindrical ones. I am not fully persuaded that it is even 
 possible to transfer a large pattern, from a flat die to a flat punch, 
 by any pressure acting simultaneously on the whole surface. 
 In those cases, if there is much work, the whole surface goes 
 down ; and the parts that form the pattern do not rise. But, 
 all that can be done in this case, is, I believe, feasible by the 
 Machine now to be described. 
 
 Plate 23, gives in fig. 3 and 4, a representation of this Ma- 
 chine ; A B and C I), are two slides, having wedge -formed 
 ends above A and below Z>, well made, well steeled, and well 
 tempered. One of these slides contains the die and the 
 other the steel prepared for the punch (see B C). These 
 wedge-ended slides are embraced by two levers E F, G 
 H, which are themselves connected by two stirrups / K and 
 L M, better shewn at fig. 3. These latter are supposed in fig. 
 2 to be broken at L M, to leave the levers E jPand G //more 
 
visible. They are formed, at the turning below, into wedge - 
 like edges a b; well hardened, that clip the nicks c d of the 
 lower lever : and at the top of the Machine their arms ef, pass 
 through the caps in n, above which they are nutted like a 
 common bolt, and made to press strongly on the main lever 
 E F. The stirrup placed to the right hand, presses in parti- 
 cular, by it's cap n, on the moveable step 0, exactly in the 
 notch q : this step having a backward and forward motion 
 communicated by the regulating screw p. Before beginning to 
 use this Machine, I make all it's arms A E, A g, D e, D d, 
 equal, when it's power (see page 162) is infinite ; and to put it 
 in a working state, I turn the screw p backward, say one half 
 round : which motion (if the screw has 20 threads to the inch) 
 makes a difference in the two arms Ar and A q of ^ of an inch, 
 and the virtual centre of the Machine is therefore 55- of an inch 
 from the former point A, that is from the edge of the slide 
 A in this fig. 3. Supposing now, the whole working lever 
 E Fto be 3 feet, and the workman's force to be lOOlbs. in 
 each arm, then by displacing the lever to any proper dis- 
 tance from F towards f, he will produce a pressure between 
 the die and the punch of 2001 bs. multiplied by 1440, the 
 number of times that ^ of an inch is contained in 18 inches. 
 That is, a pressure of two hundred and eighty-eight thou- 
 sand pounds ! 
 
 I have been seduced, by the anticipated brilliancy of this 
 result, from the regular course of description, and the plate 
 
 M m 
 
198 
 
 w #,y s, which forms the base or frame of this whole Machine has 
 not yet been spoken of. But that plate is supposed screwed down 
 to a horizontal bench, at or near the height of a man's breast ; 
 the slides or cases are fastened to it, and the man is supposed 
 to work the Machine nearly as he would a die-stock in tapping 
 a screw. This however is not indispensable ; the Machine 
 might be placed vertically, and these motions given by any 
 proper mover ; or a weight may be suspended to the arm F, 
 so as to add continuity to pressure. It is however important, 
 that the position should comport with the frequent extraction of 
 the punch in order to examine the progress of the work, or 
 cut away any redundant metal. I have before given it as my 
 opinion that much could not be expected from mere pressure : 
 but this is a pressure of a peculiar kind, consisting of immense 
 powers with very short motions. In this respect it is just what 
 was wanted, as it can be renewed and repeated frequently, 
 without loss of time. And the more to facilitate this delicate 
 operation, the hollow slides or cases B C, are made slightly 
 pyramidical, to be furnished with set-screws on the four 
 sides, by which to change the place of bearing ; and thus to 
 meet the case of a flat punch with the advantage of im- 
 pressing it by portions, so as to have only to finish it by 
 brute pressure. 
 
 The foregoing application of the principle of the differential 
 Steel -yard, is, I think, important, and founded on unobjec- 
 tionable principles ; for although by changing alone the place 
 
199 
 
 of the step o, we disturb a little the parallelism of the stirrups 
 IK, and L M ; we do it not enough to produce, any material 
 change in the theoretical result. With respect then to the lesser 
 properties of this Machine, I leave them with confidence in 
 the hands of those whom they most concern who doubtless, 
 will treat them with greater practical utility than I could 
 myself hope to do 
 
 m 2 
 
200 
 OF 
 
 A MACHINE 
 
 For Moulding Nails. 
 
 THIS Machine offers, I think, a valuable application of a well 
 known Instrument : or rather of the principle on which it is 
 founded. I allude to that parallel ruler which, by means of 
 an additional joint, keeps it's members not only parallel, 
 but directly opposite each other. In my Machine for mould- 
 ing Nails, I wanted to give motions to the two plates differ- 
 ent, yet dependant on each other. Supposing then, (Plate 
 25 fig. 1, 2, 3, 4,) the upper plate a b, to be moved up and 
 down by a lever, a screw-press, or any other first mover, I 
 connect the under plate c d, with it by two (or four) strong 
 parallel rulers ef, in such a manner, that when the plate a b is 
 drawn upward it shall extend the arms of the ruler almost to 
 a straight line, as represented in fig. 4 ; and then carry the 
 under plate with it : and when it comes down again (see fig. 3) 
 it shall not carry down the said under plate, until the same 
 arms are bent into the position f g ; that is, till the two plates 
 touch each other : the use of which arrangement I will now 
 explain. 
 
 The under side of the upper plate a b, is ground perfectly 
 flat, and bored at proper distances with holes to receive and 
 
201 
 
 hold the punches which represent the shanks of the nails 
 that are to be moulded. The lower plate c di$ ground true both 
 on it's upper and under surfaces ; the first to fit the under 
 surface of the upper plate, and the under surface to impress 
 a perfect plane on the sand below it. This under sur- 
 face, shewn in an inverted position at fig. 2, is moreover 
 covered with proper prints 1, 2, 3, &c. to form the heads of 
 the nails in question, and with proper gets (jets ?)3, 5, 6, 
 &c. for conducting the metal to every part of the surface. 
 I mean models in relief of those gets ; and the under plate is 
 further pierced with holes, placed exactly like those in the 
 upper plate, bored indeed from that (and through the aforesaid 
 prints of the nail-heads) after the parallel joints e /"have been 
 affixed. Now on another level plate with proper ledges, 
 the sand boxes or flasks, fig. 5 and 6, have been prepared; 
 and have received an obtuse pyramidical form at one stroke 
 from a competent press, the construction of which is easily 
 conceived : or this might be done by hand, if preferred. These 
 boxes, in-fine, are successively brought under the before des- 
 cribed mechanism while in the state represented in fig. 3, in 
 which all the nail models are protruded through the under plate 
 as at 1, 2, 3. The moulder now gives a stroke under the 
 following circumstances : Both the plates drop together and 
 the nail models pierce the sand while the under plate makes 
 it's surface perfectly level : but when that motion is reversed, 
 it is not the under plate which first rises, but the upper by 
 which the pail models are drawn out of their holes without dis- 
 
202 
 
 turbing the sand, for this is kept to it's place by the under 
 plate : and when, by the continued motion upward of the 
 upper plate, the parallel joints are duly extended, and the 
 nail models quite extracted ; then, and not till then, the under 
 plate leaves the compressed sand, in which are moulded as 
 many scores of nails as the mould has been made for and that, 
 in a space of time almost imperceptible. 
 
 I shall conclude the subject by observing, that the counter 
 flask or box for closing this mould is made in the same way, by 
 a smooth plate prepared in the same manner ; and which must 
 fit the former, because they are both perfectly level surfaces. 
 
203 
 
 OF 
 
 A FIRE ENGINE 
 
 Giving POWER, while heating Rooms, Liquids, -c. 
 
 X HIS Machine, though conceived many years ago, can 
 hardly yet be called an invention if material existence is 
 necessary to justify that appellation : for I have never seen 
 it in action. It may possibly be one of those fascinating con- 
 ceptions of which my noble friend the late Earl Stanhope used to 
 say <( tis a beautiful invention but 'twill not do ;" yet I give 
 it with some confidence, because of the great utility it would 
 present, if it's chief properties should fulfil my expectations. 
 
 The principal idea on which it is founded, is this : to use, as 
 power, the expansion of that air which feeds the fire ; and 
 again to employ it's heat heating liquids or rooms, or any 
 similar purpose. The form I have given to the Machine is by 
 no means the only one it admits ; nor perhaps the best : but it 
 was indispensable to give the idea (which I hope is not an 
 " airy nothing") " a local habitation and a name. 3 
 
 " 
 
 It consists, then, of two cylinders, lying horizontally, of 
 nearly equal length, but of unequal capacity : one of which 
 A B, (Plate 24, fig. 7) is an air pump with a valve in it's 
 end a, and another in it's piston, both opening to the left. 
 
204 
 
 The second cylinder C D, is the working cylinder, as much 
 larger than the former, as may belong to the principle of 
 motion already announced. This cylinder receives the piston 
 JE 9 which fits it nicely, hut is not stuffed in the present case. 
 (It may perhaps be made tight hy some of the methods, used to 
 close metallic pistons.) At all events, this piston is connected 
 with that c, hy a frame F G H /, which embraces the 
 whole Machine, in a horizontal position, though here shewn in 
 a vertical. These two cylinders are cast in one piece, together 
 with an upright cylinder, not bored K; the use of which is to 
 receive the earthen chafing dish L M 9 with it's fire, made 
 (according to my present;views)with coak or charcoal, and lighted 
 before it is introduced. It is needless to say, that this vessel is 
 let down into the cylinder K, by a kind of bucket handle 
 entering any pair of holes in the dish. The top of this latter 
 cylinder is ground to fit the flanch A N: It swings open on 
 one of the bolts and falls to again in a moment, to prevent loss 
 of time in firing. The means of doing this I do not much insist 
 on, from their extreme facility. Nor do I make it a condition to 
 use this method at all. The coak, (or perhaps the coal, or the 
 wood) might be introduced through an upright tube furnished 
 with two slides, one placed close above the top A JV, and the 
 other at a proper distance above ; so as for one to be always 
 shut. This is nothing more than the System used for feeding 
 high pressure Steam Engines only this application is to dry 
 substances, which forms no insuperable obstacle. 
 
205 
 
 When now the Machine isjired, the pistons E, and e, are 
 pushed towards b and B respectively ; the valve d having been 
 previously opened, and the valve c opening by this very motion 
 which thus clears the large cylinder of it's included air, while the 
 air in the puinp A JS } is brought into contact with the 
 fire; whence a considerable expansion ensues, and a pressure is 
 created tending at the same time to drive the piston c to the 
 right hand, and that E to the left: but acting in the latter 
 case on a larger area, the whole system moves that way, and 
 all the air in the pump A B is driven through the fire : where, 
 being much heated, it acquires great elasticity and developes 
 considerable power which, by any of the known methods, may 
 be applied to any of the known purposes. 
 
 I hope my readers will conclude here, that I allow for the dis- 
 appearance 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 cy- 
 linder C Z>, the hot air it contained rushes into the pipe o, and 
 
 N 
 
 thence goes to perform any heating operation that may be de- 
 sired. 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 pre- 
 pares the Machine for a new stroke. For, as before, the pump 
 
 N n 
 
206 
 
 or cylinder A J3, 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 them- 
 selves 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 en- 
 larged, 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 cy- 
 linder. 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 fullil any common 
 purpose. 
 
207 
 
 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 com- 
 modious. 
 
 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 com- 
 bustible : 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 dis- 
 tributing heat in any useful direction : for there is an im- 
 
 N n 2 ' 
 
208 
 
 puhive 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 is 
 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 Jl 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 airuncontaminated by burn- 
 ing, 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 pas- 
 sage, 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, 
 
209 
 
 and unmercifully freeze the bottoms. I must beg leave to be a 
 little severe on this point : since for a thinking people, as stran- 
 gers call us, we have been extremely thoughtless in this res- 
 pect : 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. Jn a word, and I am serious when I say it, the present 
 arrangements of our chimneys, is in my humble opinion, es- 
 sentially unphilosophical ; and as such ought to be speedily 
 discontinued or greatly modified. 
 
 In the above pages I have laid myself open to much ani- 
 madversion, by a kind of cast for much honest fame. I have 
 let the public into my secret / have thought aloud : And if 
 the greater part of these cogitations should prove to be imagi- 
 nary, I shall only plead, that they are drawn from the same 
 source as the many useful Machines I am known to have de- 
 voted to public utility. 
 
210 
 OF 
 
 A ROTATO-GYRATORY CHURN. 
 
 A HIS title I confess, seems very ambitious, as applied to an 
 utensil for the dairy : but I had to express the combination of 
 it's two movements that of the main shaft round 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 ves- 
 sel ; 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 ef, and the fixed wheel cd, which turns them, are 
 furnished with teeth on my patent principle ; and therefore 
 work without noise or commotion. Now, the principal shaft 
 A J5, rests on *he 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 
 
211 
 
 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 initi- 
 ated into the secrets of the dairy properly so called. 
 
 It may finally be observed, that the leaves or partitions / n, 
 fixed to the sides of the churn, (beyond the reach of the move- 
 able wings a Z>) are destined to prevent still further any general 
 motion of the butyraceous matter ; and thus to accelerate the 
 churning process : and farther these leaves, both fixed and 
 moveable may be pierced with holes, like the analogous parts 
 of other utensils of this nature. 
 
212 
 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 them- 
 selves 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 cen- 
 trifugal 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 re- 
 member. 
 
 In Plate 25 fig. 1, j4 B are two screws, perfectly like those 
 used in exhausting watery foundations ; and named of Archi- 
 
213 
 
 medes. They are placed perpendicularly in the frame C >, 
 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 Z>) is a low cylin- 
 drical 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 J3, and, being pierced 
 with many holes, to feed them amply, without exposing their 
 motion to any resistance from the stagnant water. These 
 cylinders A. IB 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 co- 
 rollary from this Machine, but of much later date. To re- 
 turn to the Helico- centrifugal Machine the screws A J5 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 shew,n 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, agaimt 
 that tendency ; and the consequence is, that the water actu- 
 
 o o 
 
214 . 
 
 ally 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 fc, 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. 
 
215 
 
 OF 
 
 A FORGING MACHINE, 
 
 For Ear Iron, Steely Sfc. square or figured. 
 
 X HIS 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 Plaje 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 JD, E, which 
 geer into and receive motion from two equnl bevil wheels F, G, 
 fixed on the main shaft H /, and to which the power is ap- 
 plied. 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, , 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 
 
 o o 2 
 
216 
 
 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 rol- 
 lers. 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 9 
 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 J3 
 C might run in steps capable of being screwed up to their 
 work, even during the process, should any such motion be ex- 
 pedient. 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 
 
217 
 
 For Mines, Mangles, fyc. 
 
 1 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 con- 
 sists (Plate 26, fig. 1,) of a wheel A JB, 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 Z>, 
 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 /, 
 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 9 destined to raise the weight K, whatever kind of re- 
 sistance that represents. Both the drums, G and H, turn on 
 round parts of the main shaft M, but are alternately con- 
 nected 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 
 
218 
 
 of the shaft as low as f, where it rests on a transverse lever 
 f g, connected to the right with the bolt a ahove men- 
 tioned, 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 immove- 
 able by means of the bolt i, which takes against some fixed 
 object at k : and thus will the weight / be raised. And 
 when this motion is achieved, the handle o is raised a few 
 inches, which brings it into contact with the obstacle/?, and puts 
 a stop to that motion of the lever E F. At the same time the 
 bolt 0, 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 / 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. 
 
219 
 
 OF 
 
 AN EXPANDING VESSEL, 
 
 For Steam Engines, Pumps, Blowing Machines, fyc. 
 
 IT is one of the simplest and most perfect operations of the me- 
 chanic art, to form a flat surf ace : 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 Z> 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 
 
220 
 
 D 3, I> 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> 
 
221 
 
 . and moreover, jP 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 ves- 
 sel, 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 y &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 
 
 pp 
 
222 
 
 i 
 
 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 soft- 
 ness 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. 13, receives the power from steam or any other agent ; and 
 the vessel C blows a fire, raises water, or does any analo- 
 gous work, without requiring any other parts than those here 
 displayed. 
 
223 
 
 OF 
 
 A GOVERNOR, OR REGULATOR, 
 
 For Wind- Mills, Water Mills, Steam Engines, -c. 
 
 Jl HIS Instrument was first intended to regulate the grinding 
 of a wind-mill ; and was used for that purpose in Kent, some 
 time before my departure for France, in 1792. It is founded 
 on the doctrine of opposite qualities and is a practical com- 
 bat between equal and unequal motions. In wind-mills, the 
 mechanism is exposed to all the variations of a capricious ele- 
 ment : and the common way of preventing these convulsive mo- 
 tions from injuring the flour, was for a man to attend a lever 
 connected with the bridge tree, (which carries the upper 
 stone) and by it i,r bring the stones nearer together when the 
 wind was strong and nearer still, when it was violent : and, 
 contrariwise, to lift again the upper stone when the wind 
 assumed a milder movement. A process this, which nearly 
 equalizes the degree of grinding, but not so nearly the quality 
 of the meal for this is found to be more heated by great, 
 than by moderate velocities. At all events I thought a Ma- 
 chine like the present, would regulate this process, as well as 
 a man ; and it was found to do so except, perhaps, in very 
 extreme cases. 
 
 This Governor, is represented in fig. 1 of Plate 27 the 
 
 p p 2 
 
224 
 
 ground work of which is the same as that of the third figure in 
 Plate 3d : for in reality the present Machine claims the pre- 
 cedence of the Dynamometer ; and may therefore, well borrow 
 a figure from it's description. A is the power-axis, receiving 
 motion from any proper shaft of the mill. It is turned back- 
 ward by that shaft, and therefore tends to raise the ball B 
 an operation equivalent to bringing the mill-stones nearer to- 
 gether. At the same time, the axis of resistance C, carries 
 round a pallet-wheel D E, and by the pallet Z>, sets the pen- 
 dulum F G a vibrating, which therefore, by every stroke, lets 
 down the ball B, and thus raises the upper mill-stone. A proper 
 position of the latter depends on the similarity of the motion of the 
 power-axis A, which winds up the ball JB, and that of the 
 axis C, which lets it down. While these are equal, the weight 
 B remains stationary, and the work goes on well. But if a 
 gust of wind increases the speed of the mover A, (the pen- 
 dulum F G confining the axis C to it's usual speed) the ball B 
 is immediately raised and the stones brought closer which is 
 what the grinding process requires : And should that gust 
 increase in violence and become a hurricane, the intermediate 
 cylinder M, while producing that effect, carries also with it 
 the cord H /, and thereby raises the bob G of the pendu- 
 lum, and thus fits this movement to the increased speed of the 
 mill : raising, sometimes, the bob to the very centre jP of it's 
 vibration, where it's oscillations become rapid enough to un- 
 wind all the excess of motion which the hurricane had oc- 
 casioned ; until, the wind subsiding, the pendulum acquires a 
 medium length, and things go on moderately as before. 
 
It may be observed, that the present form of this Machine is 
 not quite so simple as it might have been made ; nor is it so 
 simple as it first was. The required motions being much 
 shorter than those of a Dynamometer, the cylinder M 9 among 
 other things, might be dispensed with ; and one of the inter- 
 mediate wheels be likewise suppressed. And if we advert to the 
 retarding principle which resides in the pendulum, the well 
 known conical pendulum might be substituted for the present 
 one ; since from it would arise a regular or equable resistance, 
 opposed to an equable effort. Some however, might then con- 
 sider the conical pendulum as an ordinary centrifugal gover- 
 nor ; and, as a mere retarding principle, it may be thought too 
 complex for the occasion : but I think on the contrary, that it's 
 use in this connection, would make this Machine one of the best 
 of regulators, as well for steam engines as for water and wind- 
 mills of every description : especially if fitted up with my 
 Patent Geering. 
 
226 
 
 OF 
 
 A MACHINE 
 
 For Forging Nails. 
 
 J. HERE is a strong analogy between this Instrument for forg- 
 ing Nails, and the Machine heretofore given for forging Bar 
 Iron, Steel, &c. The process of kneading the softened metal, 
 by means of a pair of alternating cranks, is me very same : 
 but the acting bars or stampers A, R, are an addition to the 
 former method. Plate 27? at figs. 2 and 3, gives a represen- 
 tation of the present Machine ; which forms the nail almost 
 instantaneously, by many contacts of the stampers a b, (fig. 3) 
 on one of which the figure of the nail is engraven or rather 
 jftled across that stamper, for no hollow figure is required by 
 this System. 
 
 The second stamper c d fig. 3, whose place is at A fig. 2, is 
 quite plain on it's face ; being destined merely to keep the 
 metal to it's thickness as the particular nail here intended, is 
 a floor nail, requiring a head on two sides only. As to the 
 figured stamper b a, fig. 3, it meets a similar form in the anvil, 
 as at e: and it is by the pressure of these half matrices , that the 
 head is formed and the bar separated from the nail. It may be 
 noticed that the stampers a b, c d, are shewn in the figures, 
 as perfectly straight on the face : but the kind of motion re- 
 
22? 
 
 suiting from that of the cranks, would require a gentle curve 
 here, which a, first experiment will sufficiently indicate. 
 
 Some skill would doubtless be necessary in presenting the 
 nail bar to this Machine ; but to make this operation the easier, 
 there should be a guage, moving toward the working point e, 
 by a given quantity for each nail : say that this guage comes 
 forward at each time a distance equal to half the length of a 
 nail ; and that the thickness of the nail bar is so proportioned as 
 to contain in that length, enough of metal for the nail when 
 finished. 
 
 It remains to be observed, that the stampers or bars A, B 9 
 fig. 2, are contained, in the direction of their width ; by two 
 plates like/, connected with the anvil e, and leaving near e, 
 an opening large enough for the nail-bar to pass easily. 
 
228 
 OF 
 
 A MECHANICAL ASSISTANT 
 
 For the Tea Table. 
 
 J. SHALL, perhaps, be laughed at by some unfeeling censor, 
 for including the tea table in the field of my mechanical specu- 
 lations. But, in so doing, I seriously mean to be not only 
 attentive, but useful to the ladies who, I am old enough to 
 believe, deserve this service at my hands. My object is to ob- 
 viate for them the necessity of tediously wielding a ponderous 
 tea-pot, until real and painful fatigue ensues : thus emphati- 
 cally making a toil of that pleasure they had hoped for in 
 administering comfort to others. 
 
 This new method of tea-making admits the use of the com- 
 mon tea urn which is placed on the table near the left hand 
 of the fair distributor. This arrangement is given at figs. 4 and 
 5 of Plate 27. There, A is the Urn ; and B any common tea- 
 pot, for whose spout, the cock a, has been substituted ; and 
 the handle of which has been slightly modified, so as to make it 
 a proper centre of rotation. This tea-pot is, of course, opened 
 before it is brought into the position shewn in the figures. At 
 C b c, is placed, first of all, on the table, a stand of metal, 
 terminated upward by the stem C D which forms a vertical 
 centre to the whole apparatus : and which is sufficiently fixed 
 
229 
 
 to the table by standing on three feet, b c, &c. ; under which 
 are stretched small pieces of Caoutchouc (or India rubber), 
 which, by their adherence to the table, make the whole steady. 
 By these means, the tea-pot can be turned round, by a gentle 
 effort, till it comes under the cock of the urn, from which it 
 receives the boiling water. And, finally, the tea-board, which 
 is itself circular, revolves on the same axle C D, supported by 
 the casters or rollers ef, and bringing successively all the tea- 
 cups m, n, o, &c., to the spout of the tea-pot, where they are 
 filled without the smallest difficulty, as will appear by a further 
 inspection of the figures, and especially by an appeal to 
 experience. 
 
 The above, I should presume, is all that need be said upon 
 the subject. It remains for some rationally zealous friend of 
 this social repast, to put these (or other analogous) ideas in 
 practice : in which enterprize, should he succeed in pleasing 
 the ladies, he may depend on the approbation of every lord who 
 deserves the name. 
 
 Q q 
 
230 
 
 OF 
 
 A COPPER-PLATE PRESS, 
 
 With curious and useful Properties. 
 
 J. HIS Machine, as intimated in the Synopsis, was invented 
 expressly for the use of the lithographic art, as an improvement 
 on the roller press used in Paris when that process was first 
 introduced there. I have, however, seen in England the de- 
 scription of a Machine which takes the desired impression 
 without any rolling motion. This Machine, in that description, 
 carries a kind of scraper, or, as the calico printers would say, a 
 Doctor, which, pressing on a line only (while drawn over the 
 paper, or the paper under it), acts successively on every part 
 of the sheet, and, no doubt, gives a good impression. Of the 
 relative perfection of these methods, I do not presume to judge, 
 as it is a technical question ; and both Systems are, or have 
 been, used. But, when intense pressure, joined to much pre- 
 cision, and great economy of power, are desirable, this Invention 
 appears to me superior to any thing I have seen used for these 
 purposes. 
 
 In fig. 1 and 2, (see Plate 28), A B are two horizontal planes 
 of hard wood or metal, connected, at a proper distance, by the 
 pillars CD, shewn in fig. 1 only. E F are two Sectors of a 
 large cylinder, united at the point , either by a good hinge or 
 
231 
 
 by a joint composed of a hollow prism fixed to the upper sec- 
 tor E, and of a solid one, more acute, fixed to the lower 
 sector F; so that, in the latter case, this joint works with an 
 insensible degree of friction, and thus occasions a great saving 
 of power. 
 
 In the working of this Press, the joint just mentioned, how- 
 ever made, describes a straight line, parallel both to the floor 
 B G and the ceiling H A, which have been already shewn to 
 be parallel to each other : and thus are the joint a and the 
 sectors E F suspended to the cap or ceiling A H by a pair of 
 triangular braces / a K, which slide smoothly in two dove- 
 tailed grooves A in. Moreover, to the lower sector J^are fixed 
 two working arcs b c, one on each side of the Press, and whose 
 radii are exactly equal to that of the upper sector E (whose 
 circumference, therefore, is invisible in fig. 1.) Further, just 
 above these arcs, and in the middle of the slide IK, are placed, 
 on proper centres, a pair of grooved pulleys P, destined to 
 work the under sector, without disturbing the motion of the 
 upper one, which latter is a rolling motion under the aforesaid 
 ceiling A H. For the said purpose, a metallic cord or chain 
 is fixed at m (fig. 1.), which, passing round one of the pulleys 
 P, is led to the end n of the arc b c, n o ; and near A is fixed a 
 similar cord, which, carried round the other pulley at P, is led 
 to the angle o of the same arc b c, n o. By these means, the 
 sector F is fixed both in place and position, as long as the slide 
 IK retains it's present position and state. But, again, a system 
 
 Q q 2 
 
232 
 
 of similar cords, placed under the ceiling A H, near the edges 
 of the upper sector E, determines the place of that sector, in 
 every case, except a change of position ; for a rolling motion 
 can still have place, without occasioning any other change. 
 
 When, therefore, a pulling har, a crank and fly, or any 
 other prime mover, applied at the joint , carries that joint 
 (say) toward the pillar D 9 that motion takes place without any 
 rubbing of surface either above or below ; for, when the upper 
 section has rolled under the ceiling A ff 9 into the position 
 n p q, the lower section has rolled upon the plate s t, into the 
 position q r s : in such sort that the analogous angles o t, p r 
 of both sectors are always found in the same perpendicular 
 line or plane o t, p r; the cause of which I shall now 
 endeavour to unfold. 
 
 When a wheel, in general, rolls on or against any fixed plane 
 (and the cords m P, A P, now act the part of a fixed plane), 
 the point of it's circumference the most distant from that plane, 
 moves, in a direction parallel to it, just twice as fast as the 
 centre of such wheel, because it is twice as far from that plane, 
 the virtual centre of its motion : (an example of which is 
 found in the wheel of a carriage, whose top moves forward just 
 twice as fast as it's axle-tree.) Supposing, then, in the present 
 case, the frame la JK, with the pulleys P to glide toward the 
 right hand, the cord A o fixed near A, will turn the arc b c to 
 the right, twice as fast as the centre of the pulley P moves in that 
 
233 
 
 direction : and if this impulse had acted on the joint a, while 
 fixed in position, the arc b c would have turned too much by 
 half. But it so happens (if this expression may he used), that 
 the joint a itself moves in that direction once as fast as the 
 pulley-pin ; so, that the motion remaining to the sector F is a 
 single .motion, merely sufficient to keep the two sectors E and 
 F directly under each other, or within the same perpendicular 
 lines p r, n q s, &c. 
 
 Thus, it appears, that the turning motion of the two sectors 
 is the same ; and that a given point of the lower one will always 
 visit the same point of the corresponding plane s t, inde- 
 pendently of contact with any substance lying on it ; and that, 
 therefore, the pressure, though successive, is perpendicular, 
 having no tendency to displace or pucker the paper laid on it ; 
 besides which, it may be observed, that the power of this Press 
 is immense, from the length of the radii of the sectors E F, 
 and the absence of any rubbing motion. 
 
 I observe, further, that racks, made with teeth on my prin- 
 ciple, either singly inclined with cheeks, as in Plate 14, or with 
 teeth in the V form, will produce a more certain effect than the 
 cords and pulleys above described, provided the arcs b c, and 
 the upper sector 2, be prepared and toothed accordingly. 
 
234 
 OF 
 
 A REFLECTOR 
 
 For Lighthouses, fyc. 
 
 M. HE object of this Invention is to join economy of light with 
 splendour of effect. The means are the following : 
 
 From the nature of reflecting curves, it follows that the 
 smaller a luminous point is, the more perfectly will its emana- 
 tions he reflected ; for a focus is a point of the smallest magni- 
 tude, if, indeed, it has any dimensions. My idea, then, is to 
 make a focus of a line of light very minute in it's section, but 
 as large, in it's contents, as may be desired : thus securing a 
 considerable fasces of luminous particles while using them in an 
 economical manner. To this end (see Plate 28, figs. 3 and 4), 
 I form my reflecting surface of two distinct parts, having a 
 section common to both, viz. 1st. a concave -parabolic -spindle, 
 represented at A J3 C, as cut by a vertical plane passing through 
 it's centre ; and 2ndly, a parabolical bason E D F G (repre- 
 sented in the same manner) surrounding the former, and so 
 placed as that these surfaces have a common focus namely, 
 the circular line of which a b is the section ; the line itself being 
 shewn by an elevation passing behind the aforesaid spindle 
 A IB C. This linear focus, therefore, may be two or three 
 feet in diameter ; thus imitating the tenuity of a punctual 
 focus, while emitting a large quantity of rays. 
 
This LAMP, then, consists of an oil vessel, which is formed 
 by the outside of the parabolical bowl before -mentioned, sur- 
 rounded, in it's turn, by the cylindrical surface P H, I Q, 
 this vessel communicating with the wick -ring a JV, b O, by 
 a passage, H I, made as thin as possible, in order to leave 
 the light at greater liberty to pass downward after reflection. 
 (Where it is proper to add that the ivick-ring is drawn too thick 
 in the figure.) Now, it is well known that ah 1 rays of light issuing 
 from a point, and falling on the concave surface of paraboloid 
 belonging to that point as a focus, are reflected from it in lines 
 parallel to each other ; and, therefore, a great part of the 
 particles emanating from the linear (or circular) focus a b, 
 and impinging on the surfaces F G A B, and BCD E, will 
 be reflected perpendicularly downward, as at , 1 3 ; b, 2 4, 
 &c. and this being the case all round the common centre J5, 
 there will be formed a cylinder of light of the diameter H 
 /, diminished only by the shadows of the wick -ring, the pas^ 
 sage HN O /, and the pillar B L, when that is used, which 
 is not indispensable. 
 
 If this cylinder of light strikes on the plane mirror K H, 
 placed at an angle of 45 from their direction, these rays will 
 be reflected horizontally, and, preserving their cylindrical form, 
 may serve as a powerful beacon to the benighted mariner ; the 
 more useful, because susceptible of those temporary variations 
 of direction and aspect, long since employed to distinguish one 
 station from another. 
 
236 
 
 But, if it were desired to illuminate a large space at sea, or 
 elsewhere, the aforesaid cylinder of rays would be received on 
 a conical surface K L M, which would give it the form of an 
 immense sheet of light, of a thickness (allowing for aberration) 
 equal to the height of P L M, of the same conical surface. 
 
 I shall add only one idea namely, that to light any round 
 space, building, theatre, &c., this system might be made 
 very efficient by throwing the sheet of light M P higher 
 or lower on the walls, &c. ; or (altering the angle of the cone 
 K L M) by bringing it down to any position in or below the 
 horizon, as circumstances may direct. 
 
 It would be superfluous to say that this Lamp might be fur- 
 nished with all the advantages of the argand principle ; or, the 
 whole wick-apparatus might be superseded by a circle of minute, 
 and very numerous gas lights, forming, sensibly, the same 
 linear focus ; or a thin circular slit might produce a real ring 
 of light, strengthened by all the resources of this new and 
 splendid discovery. 
 
237 
 
 OF 
 
 A LONG PARALLEL MOTION, 
 
 For Mangles, and other Reciprocating Machines. 
 
 J.N the year 1/93 or 4, I received a written problem, desiring 
 me to give a plan of a long Reciprocating Motion, that should 
 he driven by the pit-wheel of a common water-wheel, of given 
 dimensions, and placed in a given position. In a few days, I 
 produced the drawing now represented in Plate 29. Its object, 
 as required, was to move the cylinders L M, figs. 1, 2, 3, 
 backwards and forwards, in the long grooves or gutters N O, for 
 the purpose of crushing or bruising their contents : but what 
 those contents were I never knew. I, however, produced this 
 Machine, considering it as a general thing, and of a nature to 
 perform most operations of a similar kind. The Machine 
 consists first, of a long rack / K, much like a narrow ladder 
 placed on it's edge, and in the teeth of which work those of a 
 pinion p, whose axis q is connected with the wheel r, which 
 receives it's motion from the vertical wheel s t, which is the 
 pit-wheel in question. This communication takes place by 
 means of an universal joint a?, being a mean of permitting the 
 pinion p to vibrate from side to side of the rack / K, when 
 arrived at either end of it. For example, the pinion p now 
 turns from left to right, and, being on the other side of the 
 rack, and held by the chain v, it drives the slide P Q in the 
 
 R r 
 
238 
 
 same right-handed direction, and, with the slide, the two heavy 
 cylinders L M before -mentioned ; for, the said slide P Q 
 carries across it's middle the axle-tree S T, which is the centre 
 of both these cylinders, and connects their motion with that of 
 the slide now in question. Further, there are rollers placed 
 between the cheeks V V, on which the slide moves horizontally, 
 as guided by other rollers, placed at the points 1, 2, 3, 4, &c. 
 Again, the ends of the axle-tree S T are furnished with two 
 bow-like bridles, which, connected with the pulling bars Y, are 
 again fastened to the slide P Q, at the two ends of the present 
 figure. 
 
 When, now, the pinion p turns (see fig. 1 and 3), the rack, 
 slide, and cylinders roll in the grooves, till the end of the rack 
 comes to that pinion ; which, finding no more teeth, swings 
 round the last, and taking a new position, reverts the motion, 
 till the other end of the rack comes to it, and occasions 
 another return : ad inf. This will be better seen at the third 
 figure, which is an end elevation of a part of the Machine. 
 There, P shews the slide and one of the teeth of the rack (which 
 teeth are longer than the rest, as seen near L M, in fig. 1.) 
 In this figure, we see at A, a mass of brick-work, covered by 
 the sleepers 5, 6, 7? & c -? on which the long cheeks V V 
 repose. There, also, the chains v z are seen, connected with 
 ring-bolts, which go through the bars a b, and are nutted on 
 the other side of the spring-beams c d s in order to avoid the 
 commotion which would otherwise attend every change of 
 
239 
 
 motion in the slide and cylinders. For this purpose, also, and 
 especially to prevent any waste of power at these moments, 
 there are miocti- linear wedges laid in the gutters, such as are 
 shewn at 6, which are formed so as to absorb the momentum 
 of the cylinders, in exact conformity to the time employed by 
 the pinion p y in swinging round the end tooth of the rack ; and 
 thus to save all the power and time possible. 
 
 K r 2 
 
240 
 OF 
 
 A MECHANICAL SYPHON: 
 
 Which expels Part of it's Water at the upper Level. 
 
 A.N ordinary Syphon acts by the pressure of the air on the 
 upper water, which drives it into the ascending pipe, because 
 there is a (partial) vacuum made there by the weight of 
 the falling water in the descending pipe ; this being always 
 longer than the first. Thus, in Plate 29, fig. 5, A B shews 
 the rising pipe of a Syphon, and CD the falling pipe, which is 
 longer, and sinks to a lower level D, than that A of the water, 
 which feeds the machine. E, in this figure, represents the 
 vessel containing the mechanism on which the new effect 
 depends : and which I shall now describe. 
 
 jB and C, fig. 4, are, one the ascending pipe ^J5 of fig. 5, and 
 the other the descending pipe C Z). 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 ?*, opening upwards, by means of the mecha- 
 nism we are now describing ; and closing itself merely by the 
 
241 
 
 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 by or receive it from them. Further, behind the 
 stand jP, 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 A, 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 (), 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, JS and C. When, therefore, this stroke is made, the 
 end h of the lever g A, which carries the ball, will touch the 
 screw c?, 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 
 
242 
 
 water by the weight of the piston , the valve i being kept open 
 by the action of the weight A, 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, propor- 
 tionate to the difference between the level from which the water 
 is brought, and that to which it is carried. 
 
243 
 OF 
 
 A FORCING MACHINE, 
 
 For taking on and off the Cylinders of Calico Printers. 
 
 JL HE 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 CD, 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. / K are, moreover, two ears or studs cast or welded on to 
 the top and bottom of the said frame A. J5, and at exactly the 
 same distance from the centres of the swivel E before -men- 
 tioned. These ears receive the ring-formed ends of the bars 
 JL 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 9 
 
244 
 
 by means of which the operation of the machine is duly pre- 
 pared .; 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 com- 
 plete, 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 6, 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 Mb 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 JV to the ceiling of the room just over 
 the stud JR or /, 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 JE, 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 / 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 9 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 #. This position of the 
 
 s s 
 
246 
 
 grapple would alone indicate what I have yet to observe 
 namely, that the hoiler 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 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 J5 being a 
 part of the side of the boiler. 
 
24? 
 OF 
 
 A WASHING MACHINE, FOR HOSPITALS, 
 
 WJiich confines the offensive Matter till cleamed away. 
 
 JLIOUBTLESS, 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 dole^ 
 ful abodes, was the object (30 years ago) of the VENTILATOR, 
 presented in page 1/0 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 y 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 
 
 ss 2 
 
48 
 
 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 pene- 
 tration 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 heen cut away ; and thus are nine tenths of the 
 time required to 1 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 Z), and a 
 pinion E, to turn it with, either by hand, or by any proper 
 application of power. The wheel turns the box A JB, 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 communi- 
 cation with the surrounding atmosphere. 
 
 But we said this hollow gudgeon had a second use : it is to 
 bring steam into the revolving vessel A J3, from any proper 
 
249 
 
 boiler beyond K, when that part of the process requires it. 
 There are, moreover, two partitions CD, I 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, 
 opejning 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 com- 
 munication 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 
 
250 
 
 stream of water is let through the cock /, and the wheel CD 
 
 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. 
 
251 
 OF 
 
 A MACHINE, 
 
 For propelling Boats, on narrow Canals, without disturbing 
 
 the Water. 
 
 X HE 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 con- 
 nected with a long shaft J3, reaching from the boat to the 
 hore, and, turning that wheel in the boat, to propel the latter, 
 
252 
 
 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 JS 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 dL may be placed ; for 
 this, of course, must follow the track-way, which is some- 
 times to the right and sometimes to the left of the vessel. 
 Between the two wheels c /&, 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 jB 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 
 
253 
 
 shore, notwithstanding the tendency to veer outward, given hy 
 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 /, fig. 3.), and hauled 
 taught through an eye of the socket s; by which manceuvre (the 
 points k I being lower than the centre A of the wheel) the 
 
 T t 
 
254 
 
 latter will be pressed forcibly downward, and cause that cohe- 
 sion 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 & shell, the outside of which would be what is 
 really seen in the figure (at jf), 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 /, 
 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. 
 
255 
 
 OF 
 
 A MACHINE, 
 
 For working, swiftly, the Slide-valves of Steam- engines. 
 
 JL HE 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 ; inso- 
 much, 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 : 
 
 T t 2 
 
256 
 
 where A B shew the crank-shaft of a steam-engine, working 
 hy means of slide-valves, the place of the eoccentric 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 ef> terminated 
 by an arc o, furnished (in the present instance) with Jive 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 y), 
 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 A, 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 
 
257 
 
 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 IB ; 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 eccentric ; 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. 
 
258 
 
 The foregoing completes the Third Section t)f 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 op, 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. 
 
 V 
 
 ,1 shall conclude this Part, by an observation or two on 
 the reception my System of Toothed Wheels, as described in 
 this work, has met with not intending to speak of the local 
 difficulties I experienced at a former period. .But, here, the 
 interests of truth force me to break silence. The necessity I 
 stood under of bringing out this work in Parts, has, at least, 
 had one advantage : it has given me an opportunity of watching 
 the workings of prejudice not to say of envy, and thus of 
 neutralizing, in some degree, the effects of either : from 
 which, however, I claim nothing but the right of making 
 
259 
 
 my labours the more extensively useful, by making them better 
 known. I have, then, to say that, among a few other objections 
 to the System, this error has come from so respectable a quarter, 
 that it would be unjust to Science, and injurious to truth, to 
 let it pass unrefuted. It has been said, that " my wheels are 
 a Chinese Invention ;" and this proof has been adduced of it ^- 
 namely, a sugar-mill, from China, having it's cylinders fluted 
 in a spiral direction. Now, the fact is, it would have been 
 difficult to give a better proof that the wheels are NOT 
 a " Chinese Invention ;" for two inventions are then only alike 
 when they produce the same effect, by similar means. But 
 here the effects intended are totally different. A sugar-mill 
 acts in or near the plane of the centres ; and one of it's 
 cylinders is not intended to drive the other independently 
 of pressure between them. This is so true, that the rollers of 
 many sugar-mills are not fluted at all. Besides this, my wheels 
 exert no pressure in that direction ; and if they did, they would 
 not be cog-wheels. In a word, their action is at right angles 
 to the former, and has an object of quite a distinct nature. 
 These, then, are by no means the same machine ; and, there- 
 fore, mine is not a " Chinese Invention." 
 
 Here, however, I beg not to be misunderstood ! I should 
 feel no regret at appearing on the mechanical stage, a few 
 hundred years after so ancient and astonishing a nation as 
 the Chinese ! But, in this case, truth did not permit me to 
 sanction, by my silence, this flagrant error. 
 
260 
 
 Finally, an opinion exists, somewhere, that these wheels will 
 never be generally used, from the difficulty of making them ; 
 and this opinion has been expressed, apparently, with no very 
 amiable feeling. But, amiable or hateful, the opinion is highly 
 erroneous ! It is so far from fact, that, in a competent manu- 
 factory, they can be made more cheaply than others now are ; 
 and many persons are already calling for them from every 
 quarter ; nor is any thing wanted to insure their immediate pre- 
 valence but a common degree of commercial energy. 
 
PART FOURTH. 
 
 A NEW CENTURY OF 
 
 
263 
 OF 
 
 A CUTTING ENGINE, 
 
 For large Bevil Wheels and Models, on the Patent Principle. 
 
 of the most prominent subjects of this essay, if not the 
 most important, is the System of Toothed Wheels, with which 
 the second and third Parts were introduced, and which still 
 claims a share of my readers' attention. As hinted a few pages 
 backward, it seems not enough for me to exhibit and describe 
 the System, but I must defend it against repeated objections, 
 on pain of seeing it's utility delayed, and the public deprived of 
 it's real and solid advantages. I am far from wishing to im- 
 peach the motives of those who still nourish or express dissent, 
 when they deign to bring reasons for so doing ; but the mere 
 opinion " it won't do" expressed by a man of reputation, 
 may impede, for a time, the progress of an useful discovery, 
 and thus produce a public evil. This, then, is a result I am 
 anxious to avert ; as the present System has many points of 
 excellence, against which no insuperable objection can be 
 brought. Had I not declined, already, to name either the 
 friends or enemies of the System, I might here appeal to persons 
 who highly approve of it ; and, indeed, who use it daily with 
 manifest advantage. But, I forbear. If, by means of the 
 Engines already given, and that I am going to offer, it is proved, 
 that the difficulty of making these wheels is trifling, compared 
 
 u u 2 
 
264 
 
 with their utility, one important point will be gained : I shall 
 not hear it repeated, " that the System cannot succeed, because 
 of the difficulties of it's execution" 
 
 The present Cutting Engine is shewn in figs. 1, 2, 3, of Plate 
 32. It's immediate use is to form the teeth of wooden models, 
 for casting. These are previously built as usual, and lagged 
 with bay-wood, of sufficient thickness to furnish the teeth, and 
 leave a small thickness of that wood behind or under them. 
 A B, in fig. 2, represents a wheel of this kind, ready for cutting ; 
 mounted correctly on the centre pin C Z>, which latter is so 
 formed as to be Jixable in any position on the table or bench 
 E F. Under the wheel A B, there is a kind of index a b, put 
 upon the said centre pin CD, which, by means of the clamp and 
 screw bed, can be occasionally connected with the wheel A B 
 so as to turn it, when it is itself turned by the means hereafter 
 to be mentioned. To proceed with the description : G is a 
 slide, moving horizontally on the bench E F, as seen at f e 
 fig. 3 ; this slide being the basis of the headstock G H, which 
 contains the perpendicular slide H I, itself the support of the 
 cutter-frame K L, so constructed as to turn on it's bolt above 
 /, and take any proper position over the edge of the wheel or 
 model A B. This slide, then, with it's appurtenances H I K. 
 L, moves along the bench E F, as seen in fig. 3 atfe: and 
 what gives it this motion, is, the screw g, furnished, pur- 
 posely, with a left-handed thread, working in the half-nut 
 contained in the small frame h, which contains also a jointed 
 
265 
 
 cap, that can be lifted off in an instant, and the screw set 
 at liberty. Moreover, the second use of this screw g, is to be 
 thus disengaged from it's nut, and lifted up to about i, where 
 it serves to push back the slide G towards the wheel, without 
 that loss of time it would occasion if pushed back by the work- 
 ing of the screw. The letters M A T , shew another important 
 part of the Machine, applying to the cutting-process. It is an 
 inclined plane, sloped to the same degree as the bottom of the 
 teeth of the wheel. (See the line a .) This inclined plane, then, 
 is fastened, in any proper place, on the bench E F, by the 
 wedge N, just like the puppet of a common turning lathe ; and 
 it passes through an opening in the slide G I, or rather suffers 
 this to pass over it, as better seen at M, fig. 3. Furthermore, 
 the slide / (fig. 2), after gliding down this inclined plane M G, 
 will have to be raised between each cutting : and that is the 
 office of the workman's hand acting on the lever O JP, through 
 the iron frame Q M, which is shewn at fig. 3, in another 
 direction ; and marked with the letters Q I m. In fine, the 
 slide G carries on each side of the Machine a pulling 
 bar n, connected with the said slide, and with a smaller sliding 
 piece o, the use of which is to hold a pin (seen in the figure, 
 but leaving no room for a letter of indication), which turns the 
 wheel A B, by the plate p, as the slide G recedes, and the 
 cutter-system IK L descends on the inclined plane before- 
 mentioned. Having thus adverted to all the important parts 
 of the Machine, we turn to fig. 1, for the purpose of shewing 
 
266 
 
 what the plate (whose edge is seen at o p) means ; and the 
 effect it is intended to produce. 
 
 In that figure, let J$A c be the section of any wheel it is desired 
 to cut on this principle. The width of the face of such wheel is 
 shewn by the line a b; and a c is called the projection of that face, 
 on the base of the cone of which the wheel A J3 is a portion ; 
 it's summit being at C. The line e d, shews one of the spiral 
 teeth with which the wheel is to be furnished ; and I make it 
 by this uniform process : The pitch of the wheel, whatever it 
 be, is set off from e to f: and that pitch is divided into eight 
 parts, (shewn here as four on account of their smallness) while 
 the width of the face f d, is divided into nine parts, shewn 
 here (for the same reason) by four and a half divisions. This 
 latter division is more numerous than the former, that the 
 principle may be a little overdone ; or that the teeth may overlap 
 each other by -y of the pitch : To which purpose, beginning the 
 spiral line e d at e, I move in the second circular line from e to 
 the second radial line C , and draw that diagonal which 
 forms the first part of the curved line e d. From this 
 second point, I go to the third circular line, taking also the 
 third radial line, and drawing the diagonal. This I do until 
 arrived at the fifth circular line, when I find myself likewise at 
 the fifth radial line C df. These four spaces thus gone over, 
 represent the eight parts into which this part of the face a b 
 would have been divided, had the figure been larger : and there 
 
267 
 
 remains a small division near df, equal to one half the others, 
 through which the curve e d is prolonged hy a similar process : 
 and this latter portion is what the successive teeth overlap each 
 other, as before stated. 
 
 Now, it will be seen below, that the needful circular motion 
 is given to this wheel, by a movement that takes place in a 
 direction parallel to the base a c B of this figure. The curve 
 e d, must, therefore, be transferred from the surface of the 
 cone, to this base a c B. To do this, I place a point of the 
 compasses at A, and trace, with the openings A a, A c, &c., 
 the six quadrants included in the space a c g h, which are now 
 the projections, on the base, of the circular lines a bfd on the 
 surface of the said cone. Here, a slight difficulty should be 
 obviated : strictly speaking, this projection would be hori- 
 zontal, and, of course, invisible in this position of the wheel. 
 But I have supposed the figure a c g h, turned ninety degrees 
 downward, round the horizontal line a ./?, so as to make one 
 representation suffice ; and also to shew the connection 
 of the lines a b g A, with those f d a b. The curve k I, is thus 
 a copy of that e d, only shortened in the proportion of a b to 
 a c that is, of the side of the cone a C, to the half-base 
 a A. 
 
 To secure, then, the coincidence of the pitch, as set off on 
 the circumferences a f and a g, we must divide a similar 
 portion of both into an equal number of parts, ef; and treat 
 
268 
 
 them, on the lines a c g h, as we did on those a b df; by which 
 means we shall get the curve k I, the projection of that e d. And 
 this curve k I, must be made part of a plate k I m n (about 
 Yo of an inch in thickness), the use of which is as follows : 
 
 This Plate k I m n, is no other than that marked o p in fig. 
 2; and it is there fixed to the index a b, directed to the central 
 pin C D, as it is in fig. 1 to the centre A insomuch, that the 
 pin shewn in fig. 2 near o, acting on the sloping curve k I, will 
 turn that index (and with it the wheel) by the very motion 
 which draws back the slide G (fig. 2), and lets down the slide 
 / on it's inclined plane G M. 
 
 We may remark, lastly, that as the present Machine is 
 adapted to large models, it is not, now, provided with a 
 dividing-plate, although the means of so doing are self-evident. 
 On the contrary, the division dots are seen on the edge of the 
 wheel A R, as is likewise one dot, near b, on the clamp b c, 
 from which a given distance is set off to each of the dots on the 
 wheel, so as to give the pitch required. By these means, then, 
 the wheel is divided and cut, in good, if not in exquisite divi- 
 sions ; and all the teeth take their shape from the Plate o p 
 (or k I m n of fig. 1), and are thus good, in that respect also. 
 
 To recapitulate the steps of this process The workman stands 
 behind the Machine, near E ; and, working the screw with 
 his right hand, draws back the slide G, (the power then 
 
269 
 
 turning the cutter r very swiftly) by which means, the slide 
 / glides down the inclined plane M 9 and the cutter, im- 
 pinging on the sloping face of the wheel, cuts it to the depth 
 r a ; the shape of the tooth (by the turning of the wheel) being 
 the spiral form e d of fig. 1. It may be added, that the lifting 
 lever O permits this descent of the bar Q M, because it is 
 suffered to fall lower than now represented. Thus, when the 
 slide G is arrived near h, the tooth is finished ; and the cutter 
 leaves the wheel at a : after which, the cutter-frame and slide 
 IK L are raised by means of the lever O the screw g taken 
 out of it's steps, and the slide G pushed back by it, until the 
 vertical slide / rests again on the inclined plane M, as it at 
 first did. Nothing, now, remains to prepare for cutting a new 
 tooth, but to change the division -dot, by the application of the 
 gauge or compasses, from b to the next point on the wheel ; to 
 do which, of course, the clamp b c must be loosened and re- 
 fastened by the thumb-screw d. I would just notice the 4th 
 figure to say, it is a sketch of one quarter of a bevil wheel ; 
 intended merely to shew the form and position of these teeth, 
 and the general appearance of the System. 
 
 Finally, my readers will please to advert to what has been 
 already said on the forms of these teeth, and their uses : and 
 recollect especially what was observed on the epicycloid, as 
 applied to them. It will easily be perceived, that to put 
 that form on one of these teeth would be an almost hope- 
 less attempt ! and, happily, it is not necessary. We can, 
 
 x x 
 
270 
 
 however, by using the cutter r with various slopes, and going 
 several times through each space, cut facets 011 the teeth, 
 quite near enough to the theoretical form to make them work 
 well together ; and, as before observed, nothing is wanting to 
 make the teeth perfect, but to run them together with the 
 wheels placed in due position. 
 
271 
 OF 
 
 A CENTRIFUGAL DASH-WHEEL, 
 
 For Bleachers, Dyers, Sf-c. 
 
 A O form a true estimate of the value of any new machine, it 
 is necessary to examine the nature and operation of those that 
 have been used before for similar purposes. And this is the 
 more needful here, because the present Dash-wheel is essen- 
 tially good, both in it's properties and effects. The only room 
 left for improvement, seemed to respect the quantity of work 
 done by it : and this is the chief point of comparison we 
 shall establish in what follows : 
 
 The third figure, in Plate 33, is a sketch of the common 
 Wash or Dash-wheel. The pieces of calico (or other goods) 
 are put into it through the round holes, dotted in the figure ; 
 and, by the revolution of the wheel from right to left, are 
 carried up from a to b, or nearly so ; from whence they drop 
 by their weight to about the point c, w^here they meet the angle 
 formed by the circumference of the wheel and one of the four 
 arms or partitions, by which it is divided. If the wheel go too 
 fast, the line of falling becomes more like the curve b d, and 
 the goods strike the circumference too high, and in an oblique 
 direction ; whence the blow is reduced, and the washing 
 becomes imperfect. If, on the other hand, the wheel move 
 
 xx 2 
 
272 
 
 too slowly, the pieces slide cbown the ascending partition (a) 
 before it comes to the vertex, and thus only fall from the axis 
 to the lowest point of the wheel ; whence, also, an inefficient 
 stroke. Thus, do these wheels require a moderate velocity : 
 and they are reckoned to do their work best when making from 
 22 to 24 turns, and giving, of course, four times that number 
 of strokes per minute. 
 
 The produce of these wheels is thus circumscribed by a 
 natural cause that cannot be altered namely, by the law of 
 falling bodies ; and my Invention has in view to elude the 
 shackles which confine this process, and to produce a much 
 greater effect in the same space, the same time, and with 
 the same expence of workmanship. 
 
 To this end (see figs. 2 and 4, of the same Plate) I place two, 
 four, or more boxes a, b, c, d, on as many wheels e f, toothed 
 on my Patent principle ; the latter, in the present case, being 
 about two feet in diameter, and the boxes, in length, three 
 quarters of that diameter : and of any convenient width, 
 according to the size of the pieces. The wheels ef are mounted 
 on the strong shafts C _D, which run, below, in the wheel E ; 
 and by which, also, they are turned round the common centre, 
 by means of the vertical wheel F. Further, in the centre, and 
 between the wheels ef, I place the wheel i, of half the diameter, 
 in which the main shaft runs loosely, and which is itself fixed 
 to the upper frame work, so as not to turn at all. The three 
 
273 
 
 Patent teeth at e i f shew that these wheels are to geer into 
 each other on that principle : and it is likewise seen that this 
 whole mechanism is included in a set of rails, of an octagonal 
 form, for the purpose of preserving the men from danger, while 
 in the act of charging and discharging the boxes. And here it 
 is worthy of some remark, that this process must be easier, and 
 more quickly performed, with these open boxes, than through 
 holes made in the vertical side of a Dash-wheel, on the usual 
 principle. 
 
 To account, now, for the sloping position of the shafts C D, 
 and the consequent slope of the boxes, they are thus placed, in 
 order that the goods may not drag too much on the bottoms of 
 the boxes, when passing from one end of them to the other. 
 Instead of this, they are, in fact, thrown, by the centrifugal 
 force, from the inner angle h (fig. 2) to some point k up 
 that side of the box which is then outwards ; where they 
 strike, and then fall into the contiguous angle under k, to be 
 again projected thence, after one revolution round the common 
 centre ; for, it should here be remembered, that, by the given 
 proportion of the wheels, the circulating wheels e f turn on 
 their own axis exactly one half round, for every whole revo- 
 lution round the common centre A B. 
 
 To elucidate this still further, I have outlined, at A fig. 1, the 
 central wheel i, of fig. 2, together with one of the excentric 
 wheels J5, and the lines a b, a b, &c., representing the boxes, 
 
274 
 
 are supposed to be wires with the balls b b, &c. sliding on 
 them, as is usual in some experiments on the Whirling Machine 
 (See " FERGUSON'S LECTURES/') Of these wires, I have 
 given the true directions in 12 positions of the wheel B : the 
 epicycloid b b b, &c., shewing the steps by which the ball b is 
 brought toward the common centre, during three quarters of the 
 revolution ; and also the position of the wire on which it slides : 
 where it is evident that the ball b has a tendency to preserve 
 it's station, at the first end of the wire, until the latter takes 
 the position b b c, when it forms (or nearly) a tangent to the 
 curve, and is, at the same time, at right angles to the radius 
 of motion, ^4 b d. From this moment, then, the ball is free to 
 leave the centre, and to fly off in a tangent with the velocity 
 with which the curve itself is generated at that point. We 
 might, thus, during the rest of it's flight, seek it somewhere in 
 the line bfg; but, as the wire continues to change it's position, 
 and must turn half round on it's own axis, by the time it arrives 
 at B by or describes a quarter -circle on the common centre, it 
 will again overtake the ball and, giving it a curvilinear 
 direction, will finally carry it to it's other extremity, at or near 
 the point B where it's motion first began : and thus shall we 
 give as many strokes to the ball, as half turns to the wheel B ; 
 or, in other words, as many dashes to the cloth, as we give 
 turns to the boxes, round the common centre. 
 
 By this process, then, substituted for that of the common 
 Dash -wheel, we can increase almost indefinitely, the number of 
 
275 
 
 passages of the cloth from one end of the boxes to the other ; 
 and the force of the dash will be as the squares of those num- 
 bers ; since (as FERGUSON expresses it) " a double centrifugal 
 force balances a quadruple power of gravity." If, then, with 
 four boxes we turn this machine 60 times in a minute, we shall 
 have 240 strokes in that time, instead of about 90 given by a 
 common Dash-wheel ; and this difference might be more than 
 doubled, if so desired : for should, then, the stroke be found 
 too severe, the boxes might be shortened, so as to lessen it's 
 violence, though preserving all it's frequency. 
 
 There are two other objects that present enough analogy to 
 this Washing process, to be here mentioned. The first is the 
 operation of Fulling, as applied to woollen cloths in general. 
 That process, I fear, is not performed at present in the best 
 manner possible ; and I feel persuaded that the centrifugal 
 motion might be applied to it with advantage whether as to 
 quantity of produce, or perfection of effect : and having thus 
 said, I shall leave the idea to the riper judgment of my 
 manufacturing readers. 
 
 The second object I shall just introduce is, that of Kneading 
 Dough, for bread, by the same centrifugal agency. It is well 
 known, that an ingenious baker, of Paris, invented, some time 
 ago, a method of kneading ; which consists in letting the lump 
 of dough fall successively from the four sides of a square box, 
 revolving on a horizontal centre. As this idea seems to have 
 
276 
 
 succeeded perfectly, I offer the Centrifugal System, as tending 
 to quicken, almost indefinitely, such a process ; and I particu- 
 larly recommend it to the attention of Government, and of 
 all large establishments as a mean of doing well and rapidly, 
 by power, what is frequently done slowly and ineffectually, 
 by the usual methods. Verbum sat. 
 
OF 
 
 AN HYDRAULIC LAMP 
 
 For the Table. 
 
 I CALL this an Hydraulic Lamp, to distinguish it from the 
 Hydrostatic Lamps, commonly so named : and I think the 
 distinction proper, because this Machine acts in a different 
 manner. It's principle will be seen in a moment, by turning to 
 the 5th figure, of Plate 33. If, there, we pour oil (or any 
 liquid) into the bent tube A D G at A, the first effect will be 
 to raise it to C, in the rising branch B C ; and from C it will 
 trickle down the branch CD, leaving the air, there, to occupy it's 
 own place. Continuing to pour, slowly, more oil into A the trick- 
 ling oil in C D will ultimately fill the rising tube E D, expelling 
 the air before it ; and, now, the weight to balance the column 
 in A B will be both the columns B C and E D ; whence, of 
 course, that column will rise as far above C as C is above 
 B ; that is, half-way between C and A. Here, there would be 
 a small deduction to be made, if the height B C were consider- 
 able ; but, as it is only supposed to be about a foot, the com- 
 pression of the air in CD, &c., (being about _L of a foot or 1 
 of an atmosphere) may be neglected. Continuing, then, to 
 pour oil into A, we shall again fill, not the descending tube 
 E F, but the rising tube F G ; whose column will thus be to 
 be added to those B C and ED; so that now the column A B 
 
278 
 
 will rise to A, and there abide, as long as the mouth G is kept 
 full, or nearly so. 
 
 The above is the principle of the Lamp announced in the 
 title ; whose effect depends, then, on the number of bends made 
 in the tube A D G, which number (whatever be the form) it 
 would be well to make rather greater than smaller, as the 
 height B C, &c., might be so much the less, compared with the 
 whole height of the column A J3 ; by which means, also, a 
 smaller difference in the level of the column below, would return 
 the oil necessary for the consumption of the wick above. 
 
 I have given this idea what I think a better form in fig. 6. 
 Instead of* the bent tube A G, of fig. 5, this form supposes a 
 series of air-tight cups, embracing each other ; one half of them 
 with their mouths opening upwards, and the other half with 
 theirs opening downwards. They are shewn, by a section only, 
 in this fig. 6 ; where a b c, c b a, present the under cups, form- 
 ing one piece with the outer surface of the bottom vessel d a c, 
 c a e : and, while speaking of this part of the Machine, I would 
 just indicate it's cover d e f g put on like the lid of a snuff- 
 box, and carrying a case or tube f g, the use of which will be 
 mentioned in a moment. To proceed, then, the upper vessel is 
 shewn by the edges of it's cups seen immediately over the 
 figures 123, 456, placed between the letters a b c, &c. 
 These inverted cups make also one body with the moveable 
 cover shewn between d and e, and to which is soldered the 
 tube h i which, sliding in the case / g, keeps this inverted 
 
279 
 
 vessel steady. Where note : that there is an inner tube soldered 
 into the tube h i, through which alone the oil rises, and which 
 can hardly be made too small, since it has only to supply the 
 consumption of a lamp namely, a few ounces of oil in a whole 
 evening. We may, finally, take notice of the weight placed 
 under f g, upon the said inverted vessel, and which helps to 
 counterpoise the oil in the rising tube h i ; which tube, as be- 
 fore observed, may be as many times higher than the distance 
 a d or e , as there are rising columns between the cups a b c 
 and those 123, &c. 
 
 I am not wholly prepared to say what portion of the oil it 
 might be best to re -elevate by the pressure of the aforesaid 
 weight fg ; but, if it were a considerable part of that contained 
 in the central compartment c c, that column would be shortened 
 in proportion ; and the reservoir at i would, doubtless , feel the 
 want of it to preserve it's level. I think, therefore, it might be 
 well to use, below, a cup or two more than sufficient, so as to 
 raise the main column higher than actually wanted ; and to 
 coerce this rising tendency, by a small stop-cock in the rising 
 branch, to be gently opened at the will of the person using the 
 lamp. I cannot say I have exhausted this subject ; either 
 in these respects, or as to it's technical capabilities. But I 
 have fully tried this method of raising oil above it's level ; and 
 used, for some time, a lamp made on this principle, and which 
 is still in my possession : and, at some future time, I intend to 
 bring forward an Hydraulic Machine, founded on the same 
 principles. Y y 2 
 
280 
 OF 
 
 A MECHANICAL ESSAY, 
 
 To derive Power from expanding Metals. 
 
 XT is not supposed that this Essay can lead, immediately, to 
 any result of magnitude ; but it is thought to be a subject 
 capable of further extension, and thus, finally, of future 
 usefulness. Were this process only sufficient to supply a single 
 house with water, at a small expence, the labour bestowed 
 on it would not be altogether in vain. 
 
 By General ROY'S experiments, cast iron (and steel) ex- 
 panded by 180 of heat (or, by passing from the freezing to 
 the boiling point of FAHRENHEIT) 0.013 of an inch per foot. 
 
 Supposing, then (Plate 34, fig. 1), the tubes A B C to be 
 20 feet long, their whole expansion will be 0.26 hundredths of 
 an inch. But, as the tubes are placed in the figure, the half 
 tubes A -D B D act together on the sphere D, and, both 
 together, drive it in the direction E D, more than as the above 
 expansion, in the proportion of the line E D to that A D. 
 Taking, then, one half only of the above expansion = 0.13 
 hundredths of an inch, that must be augmented in the ratio of 
 the sine of 60 degrees to radius, or in that of A D to E D. I, 
 therefore, multiply this decimal 0.13 by the fraction .1^, which 
 
281 
 
 gives 1300 to be divided by 866, or very nearly 0.15 for the 
 expansion, in the direction E D, occasioned by the two half 
 bars A D B D : and the same is true at the other angles F 
 and G. 
 
 Again, to find the expansion (and contraction) of the bars 
 a b c, we must compute their length as compared with the half 
 tubes above-mentioned ; and that length is to 10 feet (the half 
 tube A D or B Z>) as 866 is to 1000 - 11.54 nearly : the ex- 
 pansion of which is thus found : if 10 feet expand 0.13, what 
 will 11.54? Answer, 0.15. Now, as the machine acts by 
 the heating of the pipes ABC simultaneously with the cooling 
 of the bars a b c, we must add the former expansion to this 
 contraction, which gives us 0.30, or three tenths of an inch for 
 this combined effect at the three angles of the Machine. And, 
 supposing, now, any pair of bars to act directly against each 
 other, as at H I K ; and that, further, the bars be stretched 
 until the angle with the horizon be only 2 degrees, then the 
 vertical motion at / will be to the horizontal (arising from the 
 expansion aforesaid) as 1000 to 35, the sine of 2 ; that will be, 
 in round numbers, 28 times as great, or 28 times three tenths 
 of an inch = 8.4 inches, which is the stroke of this Machine in 
 these dimensions. 
 
 In this calculation, I have not forgotten that the vertical and 
 horizontal motions are nearer alike, when the bars are not 
 drawn so tight at K H ; that is, when the joint / is lowered. 
 
282 
 
 But it is equally true that, when the joint / rises still more, the 
 difference between these motions is still greater ; so that, as a 
 medium effect, I think we may reckon on an eight-inch stroke 
 in the present case. 
 
 . 
 The question now recurs, of what strength are these strokes ? 
 
 Are they sufficiently powerful to produce a useful effect with 
 so short a motion ? This I cannot say from experience ; but, 
 from the known strength of iron and steel, their power, in these 
 dimensions, must be very great. A few more observations 
 may occur in the course of the enlarged description we shall 
 give of the Machine itself. 
 
 ABC are three pipes of cast iron, well turned at the end, 
 and having conical points of iron, well steeled, let into them, 
 so as to have no tendency to bend, a b c are three steel bars, 
 placed in troughs, so as to be heated or cooled by water poured 
 into the latter. Or, these troughs may be exchanged for tubes, 
 to admit heated or cooled air, according to the means used to 
 cause these mutations. In a word, although I have represented 
 these bars as contained in troughs, I intend to finish my de- 
 scription, on the supposition that they are tubes, because I 
 intend to suppose the Machine worked by air instead of water. 
 
 To proceed : at d is an opening under the tube 13, into which 
 air enters, and C is an opening on the top of the tube which 
 emits the same air, the three pipes being made to communicate 
 
283 
 
 by means of a short junction-pipe at each of the angles D and G. 
 Here, then, the fire- place f g, fig- 2, must be noticed : the use of 
 which is both to heat and cool the Machine ; and the following 
 are the means : This little instrument contains fire in it's 
 middle compartment, and that fire draws air into the part f, 
 and drives it out of the part g. It also turns on a centre-pin, 
 seen in the figure. This chaffing- dish, then, is placed at i d, 
 and there serves a double purpose. When it's pipe g conveys 
 heated air into the pipes B A C (and out at C), it heats those 
 pipes and expands them ; but, at the same time, the pipe f 
 of this instrument draws cold air through the three tubes a b c, 
 in which are the steel bars that require to be contracted : both 
 which operations conduce alike to the above-described effect. 
 By these means, the weight w is raised, and (for example) 
 water sucked into the pump X. But, turning the fire-place 
 half round, we reverse this effect. The hot air is now drawn 
 out of the pipes j4. J5 C, and cold air drawn through them, by 
 which they are cooled; while the hot air, from the fire, is 
 thrown through the pipe g into the tubes a. b c, and passing 
 through the chimneys k I, there heat the bars and expand them, 
 both which operations concur in letting down the weight E, 
 and thus, in forcing the water of the pump to whatever destina- 
 tion was previously assigned it. 
 
284 
 OF 
 
 A MACHINE, 
 
 For Making Laces, Covering PPTiips, fyt\ 
 
 JM.ANY people, in these parts, have seen a certain machine, 
 said to have been invented by an inmate of that laudable institu- 
 tion the Liverpool Asylum for Blind People ; for the purpose of 
 making laces, covering whips, &c. I hope the similarity of 
 name will not induce any reader to suppose that I have had 
 that machine in view, and am endeavouring to cast it into 
 the shade, or purposely to supersede it. If any person should 
 thus think, I have a safe reply at hand. My own invention 
 (somewhat less perfect than it now is) was made, many years 
 ago, on purpose to serve an Asylum for the Blind in Paris ! 
 a reflection with which I shall, at once, close this, perhaps, 
 unnecessary apology. 
 
 This Machine is represented in Plate 34, at figs. 3 and 4. It 
 consists of a frame of wood or metal A JB, on which are 
 mounted the following objects : 1st, on the traverse ~B, a fixed 
 tube, having for it's base the horizontal plate a b, and rising 
 perpendicularly to near c d ; where it unites with a conical or 
 trumpet-like vessel c d,fe; the left side of which is shewn in 
 perspective, and the right side in a section only. To this 
 fixture is adjusted the spherical portion g h, h, prepared to 
 
285 
 
 receive several cuts or slits 123 for the bobbin -slides hereafter- 
 mentioned, to slide up and down in. This leads us to observe 
 the upper fixture C, which is a cylinder, terminated downward 
 by a spherical dome i k, k ; also receiving the several cuts 
 4, 5, 6, into which the aforesaid bobbin -slides pass from the 
 former slits 1, 2, 3, &c. Now it will be seen that the two 
 spherical parts thus fixed, are separated from each other by the 
 circular and horizontal slit / m, whose use is to permit the 
 pipes shewn in the section at n o, to circulate all round the 
 machine, while the bobbin -slides and bobbins k p are sometimes 
 above and sometimes under the said slit / m. 
 
 Now, then, it becomes necessary to speak of the cause of 
 this passage of the bobbin-slides from the under to the upper 
 parts of the slits 1, 4, 2, 5, and vice versa. That cause is in 
 the second dome q r, which covers, as far as it rises, the inner 
 domefi, k h; and it consists in a serpentine canal, of which a 
 section is given to the left of q, and at $, in the section of the 
 principal figure. 
 
 But to make this important piece of the Machine better 
 known, I have drawn it apart, in figure 4, on the supposition 
 that it is a portion of a cone instead of a sphere : I say a cone 
 drawn with the radii t q, t r, according to the dotted line t r. 
 The surface then of this cone, is supposed straightened in the 
 lateral figure ; and the aforesaid serpentine canal is shewn at a b 
 cde, having the rollers of the bobbin-slides placed in that canal, 
 
 z z 
 
286 
 
 at the same points a b c, &c. Here also, certain dotted lines 
 f g, h i, &c. shew the relative positions of the slits 1 4, 2 5, 
 &c. of the principal figure, and also of the horizontal slit I m : 
 whence it appears, that the revolution of the bent canal, a b 
 c, &c. must some times drive the rollers towards g i, &c. and 
 sometimes towards f h, &c. while the pipes n o pass undis- 
 turbedly round the Machine, in the horizontal slit / m of 
 both figures. 
 
 The question now arises, how is the circular motion given to 
 the outer dome q r of the principal figure ? that dome is 
 screwed to the cone r v w r, being itself of one piece with the 
 hollow tube v w, on which the wheel x y is fixed. Now, this 
 wheel x y, is driven by a vertical wheel 2, of twice the di- 
 ameter, for a reason we shall soon disclose. 
 
 It remains now, principally, to speak of the drawing -system 
 of this Machine, shewn, in small, at c, and of a natural size in 
 fig. 5 of this Plate. That Machine has also it's own tube c X', 
 working inside of the fixed tube a b, &c. and terminated, at 
 bottom, by the wheel #', which turns it by means of the second 
 vertical wheel x z, fixed on the same axis as the wheel % 
 before-mentioned, and of half it's diameter. 
 
 Supposing then, for the moment, that the mechanism c 
 derives from it's circular motion, the property of drawing 
 downward the threads from the pipe n o, and the bobbin p ; 
 
287 
 
 (being one of the twelve pair distributed round the Machine) 
 we shall now set the Machine at work, for the purpose of 
 viewing it's operation a little more narrowly. Looking at the 
 two kinds of texture, indicated in the figure below the traverse 
 J2, we see that on the left composed (in weavers' language) of 
 a straight warp, crossed by an oblique weft; and this I believe, 
 is the common texture of round, small ware, as usually woven : 
 the slope of the weft being less and less as the number of 
 shuttles diminishes, insomuch that with one shuttle that slope, 
 might become almost invisible. But in the work made on this 
 Machine, where, virtually, there are as many shuttles as threads 
 in the chain, the slope would become very perceptible, too much 
 so, perhaps, to give a desirable appearance to the work ; 
 although the rapidity of execution, from the multitude of cross- 
 ings, would compensate for some imperfection of that kind. 
 But, in fact, this Machine is intended to make a diagonal or 
 diamond texture, as in the specimen to the right hand : and 
 that is the object of the two pair of wheels a? y, with z ; and 
 x with oc z before mentioned. Their effect is this : when the 
 large vertical wheel z, has turned the outer dome and the pins n 
 o y once round the common centre, the smaller vertical wheel 
 *?' z, has turned the drawing-system c, just one half as much 
 round that centre, and thus sloped the threads coming from 
 the fixed slits in which the bobbins move, as much, in one 
 direction, as the whole turn given to the pins n o, has sloped 
 the other half of the threads in the other direction, and the 
 result has been the aforesaid diagonal texture. 
 
 z z 2 
 
288 
 
 There are a few other things to be observed by way of closing 
 this article. As the Lace, or Cord is made on the Machine by a 
 turning motion, it must be received below into a turning ves- 
 sel, or it will be twisted, and thus injured. The vessel Z), is 
 provided for that purpose ; and is turned by a cord from a 
 pulley on the axis of the wheel , coming under two vertical 
 pullies, and acting on an horizontal pulley F E, connected 
 with the said vessel ; and if preferred, the draught itself might 
 be placed in, or above, the vessel Z>, but it would not, I think, 
 produce so perfect an article. 
 
 With respect to the drawing Machinery in the Machine at 
 c, there is shewn, a flat surface just under that Machinery. 
 It's purpose is to serve as a mover for that System : To shew 
 which, in a clearer manner, is the use of the fifth figure. In this 
 figure, the drawing rollers turn in a frame abb, and carry 
 on one of their shafts a cog-wheel c or d, by which they 
 receive this motion from the pinion e ; this pinion being 
 connected with the rowel f g, and running with it on a 
 stud h, more or less removed from the centre, as circum- 
 stances may require. This rowel then, (for it's edge, formed 
 as in the figure, is indented with sharp teeth across it's 
 face) runs on the flat surface before indicated, at or near c, 
 (fig. 3) and by the rotatory motion received from the wheel X'> 
 gives a drawing motion to the rollers, the use of which has 
 already been explained ; namely, to draw down the goods as 
 they are formed. It need hardly be observed further, that any 
 
289 
 
 kind of filling may be brought down from C, to the entrance 
 of these rollers at c, and thus be included in the plaited texture ; 
 and in fact, the rollers in fig. 5, are shewn (by the dotted 
 lines) as formed to receive an object of considerable diameter, 
 as a whip, &c. that it may be wished to cover. Where I 
 remark, that this lozenge form of the grooves O, is not given 
 without a motive : the grooves are thus formed (the cylinders 
 being supposed capable of opening by a springy movement) in 
 order that, if desired, they may draw the body downward, so 
 much the faster, as it's diameter increases and thus keep the 
 covering threads at the same angle in every case. I shall only 
 add, that these movements can be permanently determined by 
 wheels, when the rowel f g, acting on the horizontal surface 
 c, has fixed the real velocities of draught required for a given 
 purpose. 
 
 This Machine then, is capable of excellent results, and of 
 a speed almost inconceivable : since at every turn, (if there 
 are twelve bobbins p, and twelve pipes n o, it makes twenty- 
 four passages of the threads among each other, answering, in 
 some cases, to an inch in length of the fabricated texture ; so 
 that, counting 120 turns per minute, (which is moderate) we 
 have 2880 passages, and 120 inches of work in a minute ; 
 equal to 200 yards per hour a quantity which does not yet 
 limit the produce of this Machine. 
 
290 
 OF 
 
 A BATTING MACHINE, 
 
 For Cotton, or FINE Filaments in general. 
 
 J. HIS Machine is represented in figs. 1 2 3 of Plate 35. It 
 is composed of a frame A jB, on which are placed two sets of 
 rollers a b, c d, round which is stretched an endless feeding 
 cloth, on the upper surface of which the Cotton is laid hy the 
 attendant. Across this frame A B, is fixed a strong board C 
 _D, having a ledge or bridge at each end, over which are 
 tightened the cat -gut strings 12, 34, &c. Moreover, across 
 this board, is fixed on proper bearings, (placed either straight 
 or diagonally) the axis e f, furnished with any proper number of 
 iron fingers 7 8, &c. which spring the cords 1 2, 3 4, &c. every 
 time they pass by them : where it may be observed, that by the 
 varied forms of the ends of those fingers, the vibrations are 
 made to be vertical, horizontal, or oblique, at pleasure. In 
 fig. 2, these fingers are seen from one end of their axis ef 
 and in figs. 1 and 3, they are shewn sideways : and in the 
 latter figure, the strings are shewn as small circles between e 
 and/", with the feeding cloth a c, stretched under them. 
 
 The following then, describes the effect of this Machine : 
 The Cotton being laid on this feeding cloth near J5, is gently 
 drawn under the vibrating cords at g h : for while this takes 
 
291 
 
 place by the action of the handle at e, the pulley f by the cord 
 i, gives a slow motion to the cylinder B, and by it to the feed- 
 ing cloth B A g h. The Cotton then passes under the strings 
 toward B A, and is greatly agitated in the passage; and when 
 arrived at A, it falls into any proper receptacle whence it is 
 taken to undergo the succeeding operations of the factory. I 
 would just mention, finally, that the axis e f, though here 
 supposed to be turned by the handle e, would, of course, re- 
 ceive it's motion from a proper power ; set on, or stopped by 
 the usual methods. 
 
292 
 
 OF 
 
 A HORIZONTAL WIND MACHINE, 
 
 For raising Water in large quantities. 
 
 A HIS Invention has for it's object, to make a more abundant 
 use of the wind's agency, at a given eoepence, than is usually 
 done : and the means, generally, are to avoid a part of the 
 expence lavished on the foundations or fixtures of wind-mills, 
 and yet to carry more sail than that system admits of. Ma- 
 chines of this nature, are chiefly used in low marshy countries, 
 where there is much water to be raised, and little solid ground 
 to build on. My idea here, is to found the whole on the 
 water, and to make that element the medium, and as it were 
 the centre of every motion. 
 
 Let us then suppose already constructed, the long and 
 narrow boat A B, figs. 4 and 5 of Plate 35 : and that there 
 is contained in the middle of it's width, a cylindrical pipe of 
 iron, (or a square wooden box) of equal length, serving as a 
 pump, by means of a spherical or square piston a or b, drawn 
 from end to end by the means soon to be described. The cost 
 of such a pump-barrel would not be great, though it should be 
 of considerable length (even 300 feet would not cost so many 
 pounds). Now, at each end of this vessel A J?, there would 
 be raised a vertical part of equal size C .D, surmounted by a 
 
293 
 
 caster, (E F) turning, horizontally, on a holloa centre, 
 through which a rope would pass from the aforesaid piston, 
 fa or bj to the boat or ship S, which is the primum mobile of 
 the System. This boat would further be made to carry as 
 much sail as possible, and to encounter as little resistance as 
 possible from the water. It's properties of carrying sail, might 
 even be enlarged, by the use of one or more out-riggers, as 
 is done in various eastern countries. 
 
 It would be proper, likewise, to give the vessel a rudder at 
 each end, and to reverse her motion by changing the sails, 
 without tacking. This is also represented in the two figures 
 4 and 5 : and, in the present case, the vessel is rigged with 
 three masts, and three large sails nearly square, yet somewhat 
 deeper on the lee side than to windward, to make the sails the 
 more governable, though as large as possible. Supposing now, 
 all these things arranged, and the rope A T O fastened to or near 
 the middle of the vessel, and to the aforesaid piston over the 
 pullies of the casters E F ; then, if the vessel sails in the long 
 ellipsis 1, 2, 3, 4, the sum of the two portions of rope N 9 O, 
 will be always the same ; and, the wind coming from , in 
 the direction of the arrow, she will sail advantageously from 
 1 to 4, or the contrary, carrying the piston from end to end 
 of the pump ; and thus exhausting it at every passage ; and 
 filling it again from the lower water. 
 
 To recapitulate and bring the several parts again to view ; S, 
 
 A a a 
 
294 
 
 in both figures, is the vessel, supposed of the best form for 
 carrying much sail : E F are two casters with their pullies ; 
 p g are two pullies at the bottom of the vertical barrels C Z>, 
 under which the rope passes to the piston at a or b, &c. In 
 fine, q r s are the three sails, and t v the two rudders, by 
 which the vessel is steered in either direction, so as to keep 
 it's wind without causing two much stress on the rope N O. 
 This consideration involves another, which must now be cleared 
 up : namely, how can this mechanism be made to produce the 
 same effect in every direction of the wind ? I answer, the whole 
 System must be moored at one end A, in the strongest man- 
 ner ; while the opposite extremity B, shall have liberty to 
 veer round that point, as a centre, through 90 degrees of 
 a circle ; some one position, between which extremes, will suit 
 every wind, on this condition, that the vessel by it's rudders, 
 keel, &c. be able to keep her ground, although the wind should 
 come from the convex side of the ellipsis ; a thing by no means 
 impossible, though less desirable than the state first repre- 
 sented. 
 
 Thus it appears, that I expect the favourable result of this 
 Systeni from two sources: the first, (but leasf) from the length 
 of this pump, which permits much water to be raised without 
 much agitation; and second, from the quantity of sail it is possible 
 to carry by this method, compared with the sails of a wind-mill. 
 My idea is, indeed, that since the power of the wind is so 
 boundless, we ought to use it more liberally than we do : and I 
 
am persuaded, that ten times as much work might be done at 
 a given expense, by such means as these, as can be done by 
 the usual methods. 
 
 Before I quit this subject, I would just observe, that there are 
 many situations in which this powerful agent might be made 
 useful, in conjunction with water power, as appliedyiperhaps, to 
 encreasing works, and being itself incapable of proportionate 
 extension. Thus, there are many water mills (used for various 
 purposes) that are obliged to wait the re -fill ing of the mill 
 pond ; and which, therefore, lose much time, although x the 
 wheel would be capable of doing even more work than is ac- 
 tually wanted. In fact, it often happens, that the worse the 
 supply of water, the better is the wheel : for this has been 
 sometimes thought a mean of making up the deficiency. In 
 such a case then, a cheap wind apparatus might double or triple 
 the effect of the wheel, and the produce of a given establish- 
 ment. But it will be objected, that the wind is an uncertain 
 helper! and thus less fit to be resorted to. This I acknowledge ; 
 but still say, that could it be used when only a breeze or a 
 zephyr, it's utility would be much extended ; and this is 
 another consequence of a system founded on the application 
 of much sail to a given purpose. Still however, as nothing 
 absolutely conclusive can be said on so variable a subject, I 
 shall not now lengthen this discussion. 
 
 A a a 2 
 
296 
 
 OF 
 
 A FLAX-BREAKING MACHINE* 
 
 IT is important, in most machines, to avoid oscillatory 
 motions : which uniformly protract the time of an operation, 
 or require * a, greater power to perform it. This consideration 
 has given rise to the form and properties of the Machine I am 
 about to describe. 
 
 In Plate 36, figs. 1, 2 and 3, represent this production. The 
 first is an elevation ; and the second is a plan, serving to 
 shew the manner of feeding the Machine. To speak first of 
 the second figure A B is a pulley, (shewn at large in fig. 1, 
 and marked with the same letters ;) it's use is to receive the 
 endless cord C D E, which is composed of three strands, 
 like the apparatus of a peruke-maker ; these strands being 
 divided at F, and passing there over three pullies placed at a 
 proper distance on the same shaft F. These pullies are 
 gently turned by that shaft, and carry with them the afore- 
 mentioned triple cord, to which, in the passage toward the 
 Machine, have been woven small handfuls of flax, by the same 
 process as the barber uses to fasten the hair of a wig ; one 
 difference however obtains : the flax is knit to the cords at it's 
 small end, and within a few inches of it, so that the root-ends 
 hang pendent, and when that part of the cord enters beyond 
 the pulley E, those ends hang round the large pulley A B, 
 
297 
 
 against the grooved surface of the outer rim : The method of 
 grooving this drum is better shewn in fig*. 3 : and it should be 
 noted, that the smaller drums C Z>, are grooved in a similar 
 form, their diameters being such as to divide exactly, in some 
 ratio, the outer cylinder E F. In tig. 1, two portions of these 
 handfulls of flax are represented by the waved lines m 
 n, drawn between the cylinders C D, and the section E 
 F of the said outer cylinder ; where it is evident, that if 
 these cylinders had, in that place, teeth like those of fig. 
 3, these handfulls of flax would appear bent which is indeed 
 the process by which the wood is broken, and the filament 
 divested of it. It appears also by the figure 1, that the cy- 
 linders C D, run on centres, fastened only to the pins of 
 the cross piece op, (shewn by dotted lines in fig. 2.) These 
 cylinders I say, are thus mounted, that there may be no 
 centres below, to gather up the flax or wood, and thus em- 
 barrass the motion of the Machine. 
 
 Adverting then, a second time, to the second figure, the 
 flax is fastened in small handfulls, to that part of the endless 
 cord that goes toward the Machine ; namely, F E, and 
 taken off from that part which comes from the Machine be- 
 hind the pulley A B : so that the triple cord before mentioned, 
 there consists of three cords, and passes round the separate 
 pullies at F. The flax being thus taken off at M, is hand- 
 ed to the charger at JV, and re -faced to that cord by it's 
 other end so as to be finished by a second passage. It 
 
298 
 
 would be superfluous to add, that the waved form of the grooves 
 in the cylinders, is intended to break the flax at every point of 
 it's length : by means simply of it's passage before those grooves 
 as conducted by the large pulley A J3, (in the centre of 
 which the main shaft turns without giving it any of it's own 
 motion) the said pulley A. J3, being turned, as before stated, 
 by the triple cord from the slow motion of the pullies F in the 
 figure. 
 
299 
 OF 
 
 A BOWKING MACHINE, 
 
 To accelerate and equalize that process. 
 
 .HAVING heard it observed by some Calico Printers, that 
 there is more or less of inequality in this process as usually 
 performed ; and that some parts of the goods are expos- 
 ed to be more acted on than the inner parts, I have thought 
 the following Machine would be useful, both to equalize and 
 accelerate that operation. 
 
 In figs. 4 and 5 of Plate 36, A B is a hollow cylinder, run- 
 ning on two gudgeons CD, with a very slow motion, and thus, 
 requiring very little power. One of these gudgeons C, is hollow, 
 for the purpose of receiving steam from a boiler, like those at 
 present used. The cylinder JL J3, is double, both around it's 
 circumference, and at it's ends, (see a b, c d, figs. 4 and 5). 
 It is also furnished with one or more doors E, through which 
 to introduce the goods ; and which doors are afterwards closed 
 with screws, like those mentioned in the article "Washing 
 Machine," of the third Part. The goods being put in, with 
 the usual doses of alkaline liquor, &c. the steam is introduced 
 through the gudgeon into the interstice a b, and thence 
 through proper openings into the body of the wheel, and 
 between the cylindrical partitions a b, c d, &c. By the 
 
300 
 
 steam, the water acquires a boiling heat ; and by the motion 
 of the wheel, is carried up in the boxes a b, &c. to the top, 
 whence it falls through proper holes upon the goods ; thus 
 keeping them wet, and steaming them at the same time. The 
 figures shew the division of the liquor into several jets 1, 2, 3, 
 &c. which are constantly falling on the goods, as the process 
 requires. The 4th. figure shews further, the effect of the 
 turning motion of the cylinder A B ; namely, that of changing 
 the position of the articles ; and offering, successively, every 
 part thereof to the steam and flowing liquid : and thus, I 
 presume, must the Bowking process become more rapid and 
 equal, than that which takes place in a Bowking-keer, unac- 
 companied with such a motion. 
 
301 
 OF 
 
 A PRINTING MACHINE, 
 
 For two Colours. 
 
 THIS Machine occupies a great part of Plate 37- It is re- 
 presented in figs. 1 and 2 ; the first being an inside view 
 of one of the cheeks ; and the second, a view endwise repre- 
 sented as broken in the middle, to gain space in the Plate. 
 As far as possible, both the parts are marked with the same 
 letters. 
 
 To begin with fig. 1, A J$ C is the cheek : being a kind of 
 shallow box with edges to strengthen it and give it thickness 
 for the steps a b, &c. These steps are strongly fixed to the 
 screws that slide in the boxes A^ 13, and the nuts of which, 
 are seen at c d. The screws enter, besides, into the heads of 
 
 the perpendicular levers D F, EG, against which these nuts 
 
 / 
 press to set the cylinders, by their steps a b, against the bowl 
 
 H. This pressure of those cylinders a b is a modified 
 effect : for the levers D F, E G, are drawn inward by the 
 pulling bars IK; which, meeting in the centre of the Ma- 
 chine, are pressed downward by the hanging bar L, to which 
 are suspended the scales and weights M, these being more or 
 less heavy according to the wish of the Printer. It were well 
 to mention a circumstance of some importance connected with 
 
 B bb 
 
this subject : If the bars / K form together an angle very 
 obtuse, the power of pressure is immense ; and the weights at 
 M might be the lighter : But, then, the degrees of pressure at 
 different angles of the bars / K would vary too much, if 
 any excentricity of the cylinders a b, occasioned any motion. It 
 is therefore best to use a sensible angle between the bars I K 9 
 together with a weight at M, so much the heavier ; by which 
 means these motions will be the more mild and manageable. 
 Proceeding with the description : e f are two hooked screws, 
 by which the pulling bars / K are raised, when necessary, so 
 as to increase the nip in any corner of the Machine, without 
 affecting the rest. It should be observed also, that the steps 
 a Z>, have dove -tailed slides screwed to them from under the rim, 
 and in it's thickness, to make them move more correctly, when 
 pressed horizontally by the nuts c d. The upper works of this 
 Printing Machine are not greatly different from those of the 
 common one. In one respect, however, I think them superior. 
 The roller, prepared for the returning blanket, is mounted in 
 a frame g, (fig. 2) which moves on a pin in the centre of the 
 Machine, insomuch that one screw and nut h, suffices to re- 
 gulate this return. This then, is an improvement, as the 
 printer has but one operation to perform instead of two. The 
 use of the piece-roller is the same as usual ; and the goods are 
 carried down on stretching bars, &c. exactly in the same manner. 
 
 But a more important property of this Machine remains to 
 be noticed. The two cylinders a b> are made to press diamet- 
 
303 
 
 rically across the centre of the bowl H ' ; so that it's shaft suffers 
 no friction from that pressure. And hence, this two-coloured 
 Machine requires no more power to work it, than a common 
 machine for one colour. 
 
 A further property of this Machine deserves attention ; hut 
 for want of room on the Plate, we are obliged to describe it by 
 means of dotted lines on the face of the present figure. At a b, 
 and at Pf, we have dotted three toothed wheels, of which one 
 is keyed on each of the mandrels, w T hile the central one 
 is placed in a frame, forming part of a slide N, (fixed on the 
 plate A T of fig. 2) and by which this wheel is moved up and 
 down at pleasure. Here it is evident, (see again fig. 1) that 
 if this central wheel rises, it will turn the mandrel , back- 
 ward ; and the mandrel b, forward : and this is a peremptory 
 method of increasing or lessening the distance between any 
 two points on the cylinders ; or in other words, of fitting the 
 colours of one cylinder into those of the other an operation 
 which is thus performed by a single movement ; while in other 
 machines it is necessary to go on both sides of the machine to 
 produce the same effect. In a word, this process is completed 
 in a few moments, by turning backward or forward a nut like 
 that h, applied to the screw placed against the side of the 
 Machine, as at P Q. 
 
 But we have another important property to speak of. The 
 colours on the two cylinders must be fitted in, laterally, as well 
 
 Bb b2 
 
304 
 
 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 I, the hent end of 
 which (/) 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 Ma- 
 chine, and performs the same office on either side as wanted. 
 This then, is another economy of time and pains ; this set- 
 ting 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 com- 
 parison. 
 
305 
 OF 
 
 A MACHINE 
 
 For clearing turbid Liquors. 
 
 J. 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 sub- 
 siding 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 
 
306 
 
 and have the liberty of leaving it by the centrifugal force, round 
 the said pins, until lost in the thickness of the cap above men- 
 tioned ; where they turn on the common centre, without 
 suffering any resistance from the surrounding atmosphere. 
 This conical cap B C, Sec. 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, there- 
 fore, will suffer the clearing process to take place sooner with 
 motion than without it ; and this is all I dare advatice 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 fldfd, 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 pres- 
 sure occasioned by this centrifugal force in the revolving fluid. 
 
307 
 
 OF 
 
 As Hydraulic Machines. 
 
 JL 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 specula- 
 tions 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 se- 
 curity against the encroaching tide ? or the means of saving 
 several months to agriculture, by the speedy disembarassment 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 analagous purpose ; 
 
308 
 
 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 inun- 
 dated 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 con- 
 tain 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 con- 
 necting 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 \i\ the act of making (what is 
 technically called) a boar, of the lower water ; and raising it 
 above the level of the valves / 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 cross- 
 beam 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 CZ), &c. It appears, near E Fin this fig. 
 1, that the vessels E F 9 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 di- 
 agonal, 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 
 
 c c c 
 
310 
 
 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. 
 
 XHIS 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 carried, it is held 
 on two mens' shoulders, by means of a bar going through the 
 ring A. Further, a rope is fastened to each of the extreme rings 
 1$ 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 Z), 
 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 nu- 
 merous ; there being always people enough at a fire. To 
 work the Engine by pulling, is nothing more than to repeat 
 many a nautical manoeuvre : and if only one man in the com- 
 pany should have learn't to sing the sailors 9 song, they would 
 soon produce " a long pull, a strong pull, and a pull al- 
 together." To be serious, a hundred men may as well work 
 
 c c c 2 
 
312 
 
 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 J^ 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. 
 
313 
 OF 
 
 A WIND MILL, 
 
 With double Power. 
 
 , A HIS 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 ques- 
 tion. It has on it two bevil wheels or pinions 0, b ; bearing 
 the same proportion to their respective wheels : one of which 
 (0) works in the wheel C, fixed to the outer shaft a c, and 
 the other (A) in the second wheel Z>, 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 /, 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 
 
314 
 
 of the wheels C D, and will retain that position if the propor- 
 tions 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 in- 
 timately connected with the welfare of their never-forgotten 
 Vaderland. 
 
315 
 OF 
 
 A WATCH ENGINE, 
 
 To extinguish incipient Fires. 
 
 J.T 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 J3 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 
 
316 
 
 Instrument can be carried there instantaneously, by the pipe 
 p g, 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. 
 
317 
 OF 
 
 A MACHINE 
 
 For Engraving the Cylinders of Calico Printers by POWER. 
 
 J_ HE 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 un- 
 equal, 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. 3) 
 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 -^, 
 (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, 
 
 Ddd 
 
318 
 
 now, this spot on the wheel JB has made one revolution, the 
 wheel A will have made ^ or 1J 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 JB another turn, the wheel A will again 
 have made 1^ 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 y and 
 The 2d. turn of 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, 
 (J/) and a porte-outil (or tool-bearer) N 9 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 re- 
 duce theSystem to any thing like regularity. And, this ad- 
 mitted, 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 
 
319 
 
 small wheel A, be likewise m : when the number in the wheel 
 jB, will come out uniformly m + -y-; 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 + j = 17, or 11 
 + -y = 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 -g of an inch thick, 
 according to circumstances. 
 
 As another example, take the following : suppose it were re- 
 quired to engrave a cylinder of 4 inches diameter or 12.56 
 in circumference, and to put twenty-five figures round it, giv- 
 ing very nearly half an inch for each figure. Then the cy- 
 linder wheel (A) must have 25 teeth ; and the porte-outil 
 
 o/> 
 
 wheel 25 + -y = 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 ofthe wheels 
 
 Dd d2 
 
320 
 
 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 sup- 
 ports the headstock CD, one of which is bolted down at each 
 end of the frame, (see also C Z> 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 man- 
 drel appears aty. This mandrel-centre is also covered with a 
 second step, over/", 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 G?, 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, (Cand 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 emerg- 
 ing from between them. 
 
 The same figure 3, shews also the position of the frog #, 
 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 
 
322 
 
 o y and another (<a?) 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. 
 
 We come, then, to it's motion in the slide, p r shews 
 a wheel, running loosely on the axis of the porte-outil ; and 
 having fixed to it a concentric rim r, with three or four waves 
 in it's circumference. Further, above s, is seen a lever, 
 turning on a pin in the stud s, and pressing against the right- 
 hand end of the rack w, when driven to the left by 'the waves 
 p , r, &c. This rack is cut into ratchet teeth as at w, in 
 which enters the catch o, as impelled by a proper spring acting 
 on it, (but not seen in the figure.) As long then, as the 
 waved wheel p r can turn, with the porte-outil JV, this last 
 described mechanism does nothing : but when p r is stopped, it 
 begins to work usefully ; for the lever s then rides on the waves 
 p r, and presses the rack w against the spring n, so that the 
 catch o, takes into some new tooth ; by which means, when the 
 spring n unbends (by the sinking of the levers into any wave p) 
 the frog is itself carried toward the right hand which is the 
 effect intended. But, in fine, how is this wheel p r stopped 
 
323 
 
 and set agoing a propos? Fig. 5 will shew this, with the aid 
 of a little imagination since our fig. 5 is a kind of trans- 
 parency rather than a regular view. The wheel m, is a crown 
 wheel, near which the wheel p r (fig. 3) turns, having a spiral g* 
 on it's hither surface, which runs between the teeth of the wheel 
 m and turns it one tooth, in each of it's own revolutions : But 
 when, after agiven number of these turns, the end of the spiral g* 
 meets with a large tooth on m, it lodges on it, and stops the 
 motion of the wheel p, and then the aforesaid waves r perform 
 the task of driving the rack w backward ; after which the 
 spring n changes the place of the frog, so as to make another 
 line of impressions round the cylinder. It remains then, only 
 to be explained, how this stoppage is itself stopped ; which is 
 thus : to the porte-outil is fastened, near g, a small arm, 
 which turns with it, and which in fig. 5 the dot t represents. 
 This arm, therefore, drives back the beak t, (connected with 
 the spring v) at every revolution of the porte-outil, thereby 
 working the small catch that hangs to that beak. This catch, 
 therefore, slides on the edge of the crown wheel m, but pro- 
 duces no effect, until it finds there, one small notch, so placed 
 as to be acted on by the catch when this disengagement is wanted 
 and, then, this motion jogs forward the crown wheel m just 
 enough to take the large tooth out of the way when the 
 spiral g begins to move through the common teeth of m, and 
 thus ceases to act on the rack till the large tooth again comes 
 to stop the wheel p, and recommence the rack's motions. 
 And thus is the place of action of the punch changed after any 
 
324 
 
 number of it's contacts with the cylinder that number being 
 doubled or trebled or more when necessary, by increasing 
 accordingly the number of common teeth in the crown wheel 
 m, before a large tooth occurs. 
 
 A few practical remarks on this mode of engraving may here 
 be added with advantage. Theoretically speaking, the punch 
 should form a portion of a cylinder, of equal radius with the 
 porte-outil wheel, taken at it's pitch line. But through the 
 relative weakness of some mandrels, a certain spring takes 
 place, which requires the punches to be more curved than that 
 wheel, and even considerably so. This also depends on the 
 size of the punch, and the fullness of the pattern. In a word, 
 it depends likewise on the method of employing the Machine 
 whether \vithfew passages, and considerable pressure, or with 
 light pressure, and many swift passages : The latter System 
 is in my opinion much the best ; since it brings the practice 
 nearer to the theory of this Machine. If, indeed, the cylinders 
 and mandrels of Calico Printers, had been originally made 
 thicker, and thus strong enough to bear the pressure without 
 sensible deflexion, this would have been, from the first, a 
 perfect process : and the nearer these objects are brought to 
 this state of inflexibility, the nearer will it's effects approach to 
 perfection ; for in all other respects it works with admirable 
 precision. 
 
 I may just add, that the facility with which the revolutions 
 
325 
 
 of this Machine are counted, has induced some persons to dis- 
 pense with the rack movement : but for small patterns with 
 numerous impressions, it is doubtless better to use it especially 
 when employing the rapid and light pressures just alluded to ; 
 and thee will become additionally interesting when the punches 
 themselves acquire a more exact form which is the object of 
 the third Punch Machine, still remaining to be described, 
 
 It is not superfluous to add, that this Engraving 
 chine is dangerous to the persons employed and should there- 
 fore be guarded behind, by a fence-bar, to prevent the hands 
 or clothes from being drawn jm 
 
 3B e e 
 
326 
 OF 
 
 A HORIZONTAL WATER WHEEL, 
 
 Probably the best of the impulsive kind. 
 
 IN this title, I have repeated that given in the prospectus : 
 nor do I think I have assumed too much in so doing. It will 
 be seen in the course of this description, on what I found my 
 opinion ; which indeed, was substantiated by the fact as soon 
 as formed : the execution having speedily followed the inven- 
 tion. The Machine, in it's different parts, is represented in 
 figs. 1, 2, 3, and 4 of Plate 40. Fig. 1 is a plan of the floor, 
 on which the upper water flows, to it's whole depth, when the 
 flood gates are opened : this floor being close over the wheel, 
 as seen in fig. 4, at c d. Further, a b, in both figures, is a 
 circular slit of the whole diameter, through which the water 
 rushes at once on all the floats of the wheel ; whose axis goes 
 up into the building through a kind of barrel, that prevents the 
 water from escaping in any other part than the aforesaid circular 
 aperture. The wheel itself is represented at ef, fig. 2 ; and fig. 4 
 is an elevation of it, with it's shaft, and a few of the floats, to 
 shew the manner of their receiving the stroke of the water. 
 A section of the ring-formed slit is also given at a b, with two 
 floats receiving the flowing water : and in that elevation is also 
 shewn two of the swan-necks by which the central part of the 
 
327 
 
 floor is supported on the framing, without stopping the water- 
 course. 
 
 Finally, the slit or aperture a /6, figs. 1 and 4, is fitted with 
 a set of cast iron curves, of which six are shewn in the Plate, 
 between c and d, and whose use is to turn aside the falling 
 water to any desired inclination ; these instruments being 
 moved at will by a proper chain of bars, reaching from one to 
 the other, and connected with eight or more levers at proper 
 intervals on the floor of the water chamber. 
 
 Thus then, it appears that this Machine has two or three very 
 important properties : 1st. all the water escapes in the same 
 direction, (relatively to the motion of these wheels) and that 
 direction concurs with that in which the wheel is made to turn. 
 2d. Every one of those fluid prisms into which the stream is 
 divided, is urged with the same velocity, because impelled by 
 the same head of water. 3d. The velocity of these jets is the 
 greatest possible, because the water is carried as low as pos- 
 sible before it is emitted ; and falls as little as possible after 
 it has struck the wheel. 4th. In fine, the inclination of the 
 floats may be made most perfect ; and their form, being that 
 of a boat slightly curved, is among the best forms possible for 
 receiving the utmost impulse from flowing water. 
 
 Although by these means much is done in favour of the 
 impulsive system, it is allowed, that, in general, a wheel act- 
 
 E e e 2 
 
328 
 
 ing by impulse, is less effective than a bucket -wheel acting by 
 the weight of the water. But the higher the fall is made, the 
 more similar these effects become. Hence, a very high fall 
 may be made to produce, by impulse, an effect equal to that 
 of the bucket -wheel. To meet, therefore, such a contingency 
 as this, I have given, in fig. 3, a cover to the water chamber of 
 fig. 4, intended to close it upward, and thus adapt it to a fall 
 of any height ; the water entering into this chamber from a 
 large pipe A, of the required length : and being compressed 
 accordingly, the result is forcible in proportion. 
 
 A few facts on the above subject will not be uninteresting. 
 When this wheel, fifteen or sixteen years ago, (for I have 
 forgotten it's exact date) was about to be put in motion at 
 La Ferte in France, several knowing ones took upon them to 
 say " that it would not turn at all." But who so astonished as 
 they, when, at twelve feet diameter, and with less than five feet 
 fall, they saw it make fifty-four turns in the first minute ! I ac- 
 knowledge, with pleasure, that these men soon expressed their 
 approbation with unsophisticated candour ; for although an 
 honest prejudice had beset them, it was un-poisoned by that 
 envy, I have more than once had to deal with in a country we 
 are accustomed to call better ! I therefore take leave, on this 
 occasion, to say to my beloved countrymen, " Go and do 
 likewise/' 
 
329 
 OF 
 
 A NEW SPINNING MACHINE, 
 
 Called, and being the PATENT Eagle. 
 
 JL HE Machine commonly used for continued Spinning, in low 
 numbers, is named a Throstle : and as my Invention acts in 
 a similar manner, I have presumed to call it an Eagle. My 
 motive is no mystery. The Machine spins more and better 
 than a throstle : and reaches, especially, to a fineness un- 
 known in tlirostle spinning. It could not, therefore, justly 
 receive a meaner name, nor even an equal one. 
 
 The present Machine then, is a superior kind of throstle, 
 the construction of which will be understood, by spinners, from 
 the annexed figures, 5 and 6 of Plate 40. As the principal 
 difference between the former machines and this, resides in 
 the toothed wheel by which it's spindles are turned, we shall 
 begin this description by adverting to it : dL B is that wheel, 
 cut, at present, into 800 inclined teeth, and working with 
 pinions of 11 teeth, one of which, with it's spindle, is shewn 
 at a b, fig. 6. The revolutions, therefore, of these spindles 
 to one of the wheel, are 7^-7- 7^> &c. ; and since the latter, 
 in spinning, makes from 60 to 70 turns per minute, the spindles 
 run at the rate of 5000 turns in that time, and might do more 
 
330 
 
 if desired by the spinner. In a word, the useful speed depends 
 on the size and weight of the spindles, the flyers, &c. 
 
 Immediately above and below the wheel A _B, are two rings 
 of cast iron, to which are screwed rims, either of wood or 
 metal, destined to hold the steps and bolsters of the spindles, 
 as is usual in a throstle, with the difference of the circular 
 form, which the wheel of course requires ; and the relation of 
 which, to the rollers, is shewn at a b, fig. 5, being a plan of 
 this Machine. Returning to fig. 6, the next object upward 
 is the roller-beam, (cast hollow for lightness) the form of 
 
 which is that of an octagon, with two brackets c d. by which 
 
 * j 
 
 it is fastened to the pillars E F: these, in their turn, being con- 
 nected with the top and bottom cross-pieces (G H 9 I K^) so as 
 to make up the frame, properly so called. All these parts are 
 placed (in section), similarly to those usually composing the 
 throstle ; and the copping motion is produced by the curve f 9 
 driven by an endless screw on the shaft hf, and acting on the 
 slide f g, and through it on the ring of which the square i is a 
 section : and on whose iron plate, in fine, the bobbins drag, 
 as they do in the throstle. In the Machine before us., the 
 rollers are driven by two side -shafts h /*, which take their 
 motion either froin a train of spur wheels placed above the 
 traverse G ff, or by bevil wheels from two small shafts, com- 
 ing under that traverse from the central shaft L M 9 to those 
 hf, and acting on the rollers by means of the bevil wheels f 
 
m, seen in the figures. Now, the rollers are contained in 
 eight heads 1, 2, 3, 4, 5, 6, 7? 8, each of which has it's 
 speed w heels in the angles n 0, &c. and receive their motion from 
 six sets of bevil wheels g, Sac. which propagate the motion 
 round each half of the Machine, from the points m and p 
 respectively. 
 
 Above this roller -beam, is the creel-ring N O, which 
 (either in one or two rows) receives the sixty roving bobbins 
 that supply the sixty spindles, of which the Machine is com- 
 posed : and whose threads pass under the eight sets of rollers 
 one thread being suppressed in each of the heads 1, 4, 5, 8, 
 on account of the columns. (This, at least, is the arrangement 
 I prefer ; but some of the Machines have been made with 
 eight threads in all the compartments.) Finally, in this frame 
 G PI, I K, is placed a ring P Q, (of glass or bright metal) 
 over which the rovings are thrown before they are put in the 
 guides behind the rollers ; so that the route of a thread in the 
 act of being spun, is shewn in fig. 5, by the line P ti, S b, 
 where it meets the bobbin on the spindle ab, before mentioned. 
 
 It may be observed here, to prevent ambiguity, that the 
 guide-boards, with their hooks, are placed below the oc- 
 tagon roller-beam q n o, Sec. as they are in the common 
 throstle; being, each, g- of the whole circumference, and of a 
 circular form on the outside, reaching, by these hooks, to the 
 point S, so as to hold the thread just over the centre of the 
 
332 
 
 spindles as at a b, fig, 6, Considering* this as a common- 
 place subject, I have not attempted to draw these boards, 
 since their form and position would occur to every constructor : 
 and this is the reason also, why I have given only the section 
 of the copping ring i, fig. 6 : nor at all shewn the top rollers 
 nor the detail of the creel on all which topics, opinions vary 
 considerably, while the things themselves are really of minor 
 importance. 
 
 There is, however, in my Patent System, something which 
 I think important, and which, therefore, I have sketched near 
 Q, fig. 6, If w x be there considered as the second commu- 
 nication shaft, a wheel % is put on it, of that kind which is 
 calculated to work in a certain geering chain, called in French 
 chaine de Vaucamon, (from the name of it's inventor) ; and 
 further, similar wheels (y) are connected with all the pins on 
 the creel, round which the chain is carried from the wheel z, 
 till it comes to it again. The consequence is, that all the 
 wheels (y) are turned by that chain, so as to untwist the rov- 
 ing while the spinning rollers draw it off the bobbins : and this 
 is so, because, in my Patent System, the rovings are over* 
 twisted, in order to admit their being made very fast, without 
 the danger of breaking. This then, completes my Patent Eagle, 
 formed, on the right hand of the figure so as to use over -twisted 
 roving ; and on the left hand, so as to spin common roving 
 in the usual manner. In both cases, the motion of the spindles 
 by geering, ensures a mathematical twist, and thus produces 
 
yarn better than common ; whence also it's fineness can be 
 carried much farther than on a common throstle. It need hardly 
 be added, that these spindles are stopped and set in motion by 
 the mechanism described in my second Part, at fig. 1, Plate 
 19 : and there mentioned as " a Machine to set-on and sus~ 
 pend rapid motions." 
 
 fff 
 
334 
 OF 
 
 A SECOND SPINNING MACHINE, 
 
 Adapted principally to Wool. 
 
 J_ HIS Machine, represented in Plate 41, figures 1 and 2, 
 may be called a Spinning-card : whose use, however, I shall 
 now suppose confined to spinning coarse yarn, or rather rovings, 
 to he re -spun on the common machines, or on machines similar 
 to my Eagle just described. It consists, in reality, of an horizon- 
 tal card A B, having it's feeding rollers, it's flyer, &c. adapted 
 to perform, in a perpendicular position, what those several parts 
 do, in an horizontal one, on the common carding engine. All 
 this is so well known, that I have not thought it necessary to 
 draw it in these figures ; but merely to say, that in this Machine, 
 those operations are performed on the left hand, as at A, 
 where is introduced a broad flat ribbon of wool, duly made on 
 a preparing card, and laid on edge in a box at C, from whence 
 it is drawn by the feeding rollers, &c. so as to cover the whole 
 of the central card A B. Now, round this central card, are 
 placed, ten or more small fillet cards, 1, 2, 3, 4, &c. being 
 at different heights on the central one; by which arrangement, 
 the whole surface of the latter is stripped by these cards, and 
 as much filament collected on each, as is sufficient to form a 
 thread or roving, as before mentioned. But, further, these 
 small cards have to be stripped in their turn : and that is done 
 
335 
 
 by the circular combs a b, which being placed obliquely to the 
 cards, receive motion from them, and gather a regular mass 
 of filament of a size fitted to become the yarn or roving in 
 question. Nor need this roving be re-drawn, by rollers, before 
 it is twisted : for it is the property of the bobbins D E, fig. 2, 
 to draw mathematically : and with any speed that shall have 
 been determined. If we examine how this is done, we shall 
 see at bottom, two wheels F G, (toothed on the patent prin- 
 ciple) one of which drives the spindles and flies, and the other 
 the bobbin D E : the wheel that drives the bobbin having 
 a few teeth more than that which drives the spindles whose 
 pinion is the same in number as that of the bobbin. Thus, 
 therefore, the bobbin goes as much faster than the spindle as 
 is necessary to take up all the wool furnished by the comb, 
 and to the comb by the small card, which receives it from the 
 central card A J3 ; where note that the draught, by this 
 difference of motion is not variable, but determined : since the 
 heads of the bobbins E D, are a hollow inverted truncated 
 cone, on which the yarn cannot remain for in winding, it 
 drives downward that which is already wound, so as to fill 
 the whole bobbin from the head a reason for the conical shape 
 of the latter object. 
 
 It will appear by the upper figure, (which is a plan of the central 
 card, and the small cards, 1 2, &c.) that the latter receive their 
 motion from the chain // /, by means of the train of wheels 
 K L, turning on studs in the upper cross-piece. Suffice it 
 
 Fff2 
 
336 
 
 to add, that the centres of these cards, of the combs, Sac. 
 are fixed to the rings by proper cramps, as will be easily con- 
 ceived. I have offered to sight, only the essential parts, to 
 avoid confusion : and I presume to hope every thing important 
 will be thus seen without difficulty. 
 
 In my present view of this Invention as a preparing Machine, 
 I would observe, that the central card is only considered as a 
 distributor, and that I should, now, add to it a System of 
 machinery to make it a forced distributor. I had, indeed, 
 prepared this very System to be patentized many years ago : 
 but the delays that occurred then, followed by the Restoration, 
 (which gave me an opportunity of coming to England ;) made 
 me suspend this intention respecting a method, perhaps, 
 the only thing wanted to make this Machine in all respects 
 excellent. 
 
 In the small figure 5, (Plate 41) x y is supposed to be the 
 section of a central card, such as A J3, fig. 2 ; and the hori- 
 zontal lines between x and y, shew the height of the card teeth. 
 Of these, I take out a portion in several perpendicular lines 
 round the card say, at an inch distance from each other : the 
 intervals thus stripped, being about ^ of an inch in width : 
 and in all these upright slits, I introduce a blade x y, (whose 
 transverse section is like that of a card wire) and whose edge 
 is undulated as at a b. Finally, to these blades is given, (by 
 a proper Machine) a slow up-and-down motion, which makes 
 
337 
 
 them push off the filament from the card wires at the highest 
 points of the waves, and suffer the wires to retain these fila- 
 ments at the lowest points; whence it follows, from the motion 
 just mentioned, that these points of reception and exclusion 
 of filament, are constantly changing on the surface of the whole 
 card, and that, therefore, the card will never be totally clog- 
 ed with wool as it is in the common process. It will be seen 
 that the use of this System need not interrupt that of the com- 
 monjtfyer, (or stripping card) whose use is to keep the teeth 
 in working order, and to discharge a part of the obtruding 
 filament. 
 
 In terminating this article, I cannot resist the desire of re- 
 commending this whole subject to any opulent English Manu- 
 facturer, whose zeal and public spirit, are commensurate with 
 the scope which these hints embrace, and to which they tend, 
 if duly appreciated. 
 
338 
 OF 
 
 MT PARALLEL MOTION, 
 
 As applied to HEAVY Steam Engines. 
 
 \V HILE this Invention, as described in page 30 of the first 
 Part, is allowed to possess curious properties, and to be a 
 pretty thing, opinjons do not all concur in declaring it, es- 
 sentially and generally, a good thing. Nor could I be unjust 
 enough to insist that it is so, in every kind and magnitude of 
 application. I have, however, convinced myself that it is suscep- 
 tible of practical excellence, as a, first motion to steam engines, 
 whatever be their dimensions ; and have, therefore, presumed to 
 re-produce it,with those modifications which are required to make 
 it so. In thus acting, I have again preferred the useful to the 
 agreeable, and in some measure inverted the order of my subjects. 
 But I trust this deviation will be excused, in favour of the motive 
 and the result ; on both which I feel a good degree of confidence. 
 
 To obviate the point of mechanical weakness in this Parallel 
 Motion, (see Plate 41, fig. 3,) I have doubled it's parts ; and 
 brought the piston rod a b, to act, at once, on two of the 
 circulating wheels c d, placed exactly opposite each other, and 
 rolling, as before, on the inside of the fixed wheels f e, so as 
 to produce the rectilinear motion, by the action of the piston 
 rod on them both. And to make their respective motions 
 one, (as connected with the fly 13 A} this latter is fixed to a 
 shaft common to the two wheels g h } and by which, therefore, 
 
339 
 
 the two other wheels i k, fixed to the crank shafts m n> are 
 kept in due position. Thus, then, is all winding or twisting 
 motion done away : and, therefore, can this System be em- 
 ployed in engines of every required power. Nor need I add, 
 (what will be generally allowed) that much of the expence, 
 and of the retardation, which a given engine suffers from the 
 beam, the connecting rod, &c. will thus be completely obviated. 
 
 I must, however, stop every gainsaying mouth, on the cir- 
 cumstance of using geering between the engine and the fly 
 a system which I ackowledge to have been hitherto an evil ; 
 though, perhaps, a necessary evil as giving (by a simple 
 method) a double speed to the fly from a single motion of the 
 piston. At all events, in this shape, I submit only to a very 
 common difficulty and might there rest my apology. 
 
 But I should have hesitated to go thus far,had I not foreseen that 
 all the evil arising from this use of wheels, can easily be avoided by 
 my geering : by means of which I am bold to say, every vestige of 
 shake or backlash may be destroyed ; and this method of working 
 a steam engine be made as silent as when a beam is used : in which 
 case, considerable advantages must accrue from this method. 
 
 To come to the point : the small figure 4, in Plate 41, re- 
 lates to this subject. My geering is there seen in three forms 
 or applications each one intended to bring the above property 
 into play. The part n 0, represents the manner in which two 
 wheels with singly -inclined teeth, work together when one of 
 
340 
 
 them is furnished with a cheek, as directed in fig. 3 of Plate 
 14. But here, in addition to that, the teeth of both wheels 
 are sloped more on one side than on the other, so as to assume 
 a wedge -like form : insomuch, that in beginning to work, (if not 
 perfectly formed) the wheels would not occupy the same plane. 
 For, in fact, the cheek screws press home the cheek o against 
 a number of thin washers all round the wheel, and thus only 
 draw the edged-formed teeth into each other as they become 
 bedded, and successive washers are taken away. Hence, a 
 good degree of precision is obtained accompanied with little 
 friction, and thus with great durability. 
 
 But we stop not here. The part p q of this figure, shews a pair 
 of wheels doubly inclined one of them only, being made in two 
 halves, which are connected together by screws and washers, like 
 that just described. Here then, another degree of friction is got 
 rid of namely, that of the cheek o : but still, a small degree re- 
 mains, (dependent on the double versed sine of the angle formed 
 on the wheel's circumference, by the thickness of a tooth). This 
 quantity, is indeed, very minute ; and brings, perhaps, the whole 
 near enough to perfection. To do, however, completely away 
 with &\] friction, (see my preceeding statement) as well in the 
 wheel acting backward, as in that acting forward, we must do 
 what is shewn in the parts r or s of fig. 4 : we must have a pair of 
 of V wheels on the same shaft, with the power of turning one of 
 them in reference to the other ; and then connecting them by 
 proper screws, &c. to preserve the position thus given : by which 
 means, in a word, all shake or backlash will be completely an- 
 nulled. 
 
PART FIFTH. 
 
 A NEW CENTURY OF 
 
OF 
 AN ADDING MACHINE, 
 
 Or Machine to Cast up large Columns of Figures. 
 
 J. HIS Machine is not, generally, an arithmetical Machine. 
 It points lower : and therefore promises more general utility. 
 Though less comprehensive than machines which perform all the 
 rules of arithmetic, it is thought capable of taking a prominent 
 place in the counting-house, and there of effecting two useful 
 purposes to secure correctness ; and thus, in many cases, to 
 banish contention. It is represented in figs. 1, 2, 3, and 4 
 of Plate 42, and in figs. 3 and 4 of Plate 43. 
 
 There are two distinct classes of operations which may be 
 noticed in this Machine : the one that does the addition, 
 properly speaking ; and the other that records it by figures, 
 in the very terms of common arithmetic. The first operation 
 is the adding : which is performed by means of an endless geer- 
 ing chain, stretched round the wheels A B C D, (fig. 1) and 
 over the two rows of smaller pulleys abcdefghi; where, 
 observe, that the chain is bent round the pulley A> merely 
 to shorten the Machine, as otherwise the keys 123, &c. to 9, 
 might have been placed in a straight line, and thus the bending 
 of the chain have been avoided. 
 
 G gg2 
 
344 
 
 The chain, as hefore observed, geers in the wheels B and 
 D, which both have ratchets to make them turn one way only. 
 Now, the keys 1 2, &c. have pulleys at their lower ends, 
 which press on the aforesaid chain more or less according to 
 the number it is to produce, and the depth to which it is suf- 
 fered to go by the bed on which the keys rest, when pressed 
 down with the fingers. Thus, if the key I be pressed, as low 
 as it can go, it will bend the chain enough to draw the wheel B 
 round one tooth which the catch E will secure, and which the 
 wheel C will permit it to do by the spring F giving way. But 
 when the key 1 is suffered to rise again, this spring F will 
 tighten the chain by drawing it round the pulleys jl and Z>, thus 
 giving it a circulating motion, more or less rapid, according to 
 the number of the key pressed. Thus, the key 5 would carryfive 
 teeth of the wheel B to the left ; and the catch E would fix the 
 wheel B in this new position : after which the spring T would 
 tighten the chain in the same direction and manner as before. It 
 is thus evident, that which-ever key is pressed down, a given 
 number of teeth in the wheel B, will be taken and secured 
 by the catch E ; and, afterwards, the chain be again stretched 
 by the spring F. It may be remarked, that, in the figure, all 
 the keys are supposed pressed down: so as to turn the wheel B, 
 a number of teeth equal to the sum of the digits 1, 2, 3 to 9. 
 But this is merely supposed to shew the increasing deflexion of 
 the chain, as the digits increase : for the fact can hardly ever 
 occur. We draw from it, however, one piece of knowledge 
 which is, that should the eye, in computing, catch several 
 numbers at once on the page, the fingers may impress them at 
 
345 
 
 once on the keys and chain ; when the result will be the same 
 as though performed in due succession. 
 
 Thus then, the process of adding, is reduced to that of 
 touching (and pressing as low as possible) a series of keys, 
 which are marked with the names of the several digits, and 
 each of which is sure to affect the result according to it's real 
 value : And this seems all that need be observed in the 
 description of this process. It remains, however, to describe 
 the 5th. figure, which is an elevation of the edge of the key- 
 board, intended to shew the manner in which the two rows 
 of keys are combined and brought to a convenient distance, 
 for the purpose of being easily fingered. 
 
 We now come to the other part of the subject that of re- 
 cording the several effects before-mentioned. The principle 
 feature in this part, is the System of carrying, or transferring 
 to a new place of figures, the results obtained at any given one. 
 This operation depends on the effect we can produce by one wheel 
 on another, placed near it, on the same pin ; and on the possibility 
 of affecting the second, much less than the first is affected : Thus, 
 in fig. 3 and 4, (Plate 42,) if A be any tooth of one such wheel, 
 placed out of the plane of the pinion B, it will, in turning, produce 
 no effect upon that pinion : but if we drive a pin () into the tooth 
 A, that pin will move the pinion B one tooth (and no more) every 
 time this pin passes from a to b. And if we now place a second 
 wheel (F) similar to A, at a small distance from it, so as to 
 geer in all the teeth of the pinion B, this latter wheel will be 
 
346 
 
 turned a space equal to one tooth, every time the pin a passes 
 the line of the centres of the wheel and pinion A J5, (say from 
 a to A.) It may be added, likewise, that this motion, of one 
 toothy is assured by the instrument shewn at E Z>, which is 
 called in French a tout ou rien, (signifying all or nothing) and 
 which, as soon as the given motion is half performed, is sure to 
 effect the rest : and thus does this part of the process acquire, 
 likewise, a great degree of certainty if indeed, certainty 
 admits of comparison, 
 
 It is then, easy to perceive, how this effect on the different 
 places of figures is produced : and it is clear, that with the 
 chain motion just described, it forms the basis of the whole 
 Machine. There is, however, one other process to be men- 
 tioned, and as the 2d, figure is before us, we shall now advert 
 to it. In adding up large sums, we have sometimes to work on 
 the tens, sometimes on the hundreds; which mutations are 
 thus performed : The wheel J5, (fig. 2) is the same as that 
 J5, fig, 1 ; and it turns the square shaft B G, on which the 
 wheels k I slide. The wheel / is to our present purpose. It 
 is now opposite the place of shillings ; but by the slide m, it 
 can be successively placed opposite pounds, tens, hundreds, 
 &c, at pleasure : on either of which columns, therefore, we 
 can operate by the chain first described the wheel B being 
 the common mover. 
 
 We shall now turn to figs. 3 and 4 of Plate 43, which give 
 another representation of the carrying-mechanism, adapted 
 
347 
 
 especially to the anomalous carriages of 4, 12, and 20, in 
 reference to farthings, pence, shillings, and pounds, and then 
 following the decuple ratio. 
 
 In fig. 3, k I represent the two acting wheels of the shaft 
 JB G y fig. 2 ; the latter dotted, as being placed behind the 
 former ; these wheels, however, are not our present object, 
 but rather the carrying system before alluded to ; and des- 
 cribed separately, in fig. 3 of Plate 42. A, in figures 3 and 4 
 (of Plate 43) is the first wheel of this series. It has 12 teeth 
 with three carriage-pins (or plates) a, which jog the carrying- 
 pinion B, at every passage of 4 teeth ; thus shewing every 
 penny that is accumulated by the far things. This is so, because 
 the farthings are marked on the teeth of this first wheel in this 
 order 1, 2, 3, ; 1, 2, 3, &c. and it is in passing from 3 
 to 0, that this wheel, by the carriage -pinion -B, jogs forward 
 the pence wheel C one tooth : But this pence wheel is divided 
 into 12 numbers, from to 11 ; and has on it only one carry- 
 ing-pin (or plate) b ; so that, here, there is no effect produced 
 on the third wheel Z>, until 12 pence have been brought to 
 this second wheel C, by the first, or farthing wheel A. Now, 
 this third wheel Z>, is marked, on it's twenty teeth, with the 
 figures to 19, and makes, therefore, one revolution, then 
 only, when there have been twenty shillings impressed upon 
 it by twenty jogs of the carriage-pin />, in the second wheel C. 
 But when this wheel D has made one whole revolution, it's 
 single carriage-pin c, acting on the small carriage -pinion, 
 like that c d, (but not shewn) jogs forward, by one tooth, the. 
 
448 
 
 wheel E, which expresses pounds ; and having two carriage - 
 pins e f, turns the wheel called tens of pounds, one tooth for 
 every half turn of this wheel E : and as, on all the succeeding 
 wheels, to the left from E (see fig. 2, Plate 42) there are two 
 sets of digits up to 10, and two carriage -pins; the decuple 
 ratio now continues without any change : and thus can we 
 cast up sums consisting of pounds, shillings, pence, and far- 
 things, expressing the results, in a row of figures, exactly as 
 they would be written by an accountant. The opening, through 
 which they would appear, being shewn in fig. 1, at the point 
 w y corresponding with the line x y of fig. 2 in the same Plate. 
 
 I shall only remark, further, that the figures 3 and 4 in Plate 
 43, are of the natural size, founded, indeed, on the use of 
 a chain that I think too large ; being, in a word, the real 
 chain de Vaucanson^ mentioned in a former article : and that the 
 figures of Plate 42 are made to half these dimensions, in order 
 to bring them into a convenient compass on the Plate. 
 
 I would just repeat, that I have not attempted here an arith- 
 metical machine in general ; but a Machine fit for the daily 
 operations of the counting-house ; by which to favour the think- 
 ing faculty, by easing it of this ungrateful and uncertain labour. 
 Had I been thus minded, I could have gone further, in a road 
 which has been already travelled by my noble friend the late 
 Earl Stanhope, (then Lord Mahon) but I took a lower aim ; 
 intending in the words of Bacon " to come home to men's 
 business and bosoms. '' 
 
349 
 OF 
 
 A ROTATORY PUNCH MACHINE 
 
 to my own Engraving Machine. 
 
 is highly desirable, (not to say indispensable) in the use of 
 my engraving Machine, to have punches not only of the true 
 cylindrical form, but exactly of the proper length. (See the 
 remarks on this subject, in the description of that Machine). 
 It is, therefore, a matter of consequence, to be assured that 
 both these circumstances unite ; and to unite them without 
 depending on personal skill, whenever the work can be accom- 
 plished without such dependence : and this is the object of the 
 present rotatory Punch Machine. Adverting first to the length 
 of the punch : that is insured by having a kind of slide on the 
 Punch Machine, formed like the frog spoken of in the above 
 article Engraving Machine. In the 5th. figure of Plate 43, 
 this slide is shewn at , and it is at exactly the same dis- 
 tance from the centre of motion A, as the bottom of the frog- 
 plate fig. 3 Plate 39 is from it's centre of motion. Thus, 
 the bottom of the punch is filed straight, once for all, and 
 being fixed in proper clams, as in the figures, the shaft A is 
 set a -turning, by power from which motion two uses are 
 derived : first, the cylindrical form is given to the punch by 
 presenting to it, in it's revolution, a file duly wedged on the 
 (now fixed) slide of the Machine B B; against which it is kept 
 
 fthh 
 
350 
 
 turning, till, by a due depression of the centre A, the radius 
 is brought to the length required, and the surface perfectly 
 formed and smoothed. This being achieved, the cams c d, are 
 fixed to the slide B B, and to the turning body A d, so 
 that when the die fis moved toward the left hand by the said 
 cams, the prepared punch gently presses on it, and begins to 
 receive it's impressions ; which are gradually deepened by the 
 set screws g h, fig. 3 ; till, at once, the proper radius is given, 
 and the engraving sufficiently transferred from the die to the 
 punch an operation which this process is calculated to perform, 
 rather by means of frequent and gentle contacts, than by slow 
 and heavy pressure. It need not be added, that the motion 
 of the slide B B is reciprocated by the spring C, against that 
 D, after each forward motion given to it as begun by the 
 cams c d, and continued by the contact of the die and punch, all 
 which a mere inspection of the figures will sufficiently explain. 
 It is likewise evident, that the figs. 5 and 6, shew, both, the 
 fcame objects, namely: the regulating wedges i k, the upper 
 set screws g h, and the rollers E 9 on which the slide vibrates 
 during the operation of the Machine. 
 
351 
 OF 
 
 A PORTABLE PUMP, 
 
 To be worked by the Feet. 
 
 J.T is not solely because, to work with the feet is a good 
 method of employing the strength of men, that this device is 
 presented to the mechanical public ; but it is with the view of 
 so employing the feet and hands, that they may occasion a 
 constant and equable flow of water. The means, (see Plate 44, fig. 
 1) are, to provide the man with two supports a b for his hands, 
 and two pedals c d for his feet, by which the two rods e f 
 are worked ; and by them, through the cords or chains g 
 h, the piston rods i and k. Of the latter, the one which 
 answers to the lower pump /, goes through the upper 
 piston, whose rod is i : and the pistons are both con- 
 structed in the manner shewn in fig. 2 ; that is to say, the 
 piston has no body , fitting the pump barrel : but a triangular 
 bar <z>, going diagonally across the pump barrel, (which is 
 square) and carrying two wings or valves y z ; which, both 
 together, fill the barrel when down, and leave it as empty as pos- 
 sible when up, by which motion the chains a e are slackened. 
 Further, these pistons, with their rods, are heavy enough to 
 raise the pedals, the instant the man raises his feet in any 
 degree : so that, by a proper combination of the motions of his 
 hands and feet, he can let down a given piston, and begin 
 again it's ascending motion before his effort has wholly ceased 
 
 nhh2 
 
352 
 
 on the other pedal. A mean this, of producing a constant and 
 equable rising motion in the column of water through the pumps 
 k I; and a mean also, of doing more work with a given fa- 
 tigue, than would be possible in a pump whose motions were 
 merely reciprocal, and the water of which, in rising, would 
 be subject to any unequable or convulsive motions. 
 
 In general, this portable pump was made (many years ago) 
 with a view to being easily carried to any field or garden, 
 bordering on a river, and worked on it's bank ; the flexible suc- 
 tion pipe p being thrown into the river, or a well, as occasion 
 might require. To this end, the whole frame (as is evident 
 from the figure) can be folded up into a kind of faggot : and 
 thus it's transport from place to place, be made perfectly 
 commodious. 
 
353 
 
 OF 
 
 THE BISECTING COMPASSES. 
 
 J.T often happens, that from a central line, (in drawing for 
 example) we want to set off, quickly, many equal distances 
 on each side ; or between two given lines we want a central 
 line ; to perform either of which operations, is the use of the 
 Instrument just mentioned. 
 
 It is represented in Plate 44. figs. 3 and 4, where A B is 
 the central point, being cylindrical in the greatest part of it's 
 length, and conical at E B. It slides correctly in two cannons 
 or swivels E & A, which also have two short axes or trunnions, 
 on which first, the double compass joints C D turn ; and 
 second, the two pairs of arms FG. I have called these cannons, 
 sivivels, that I may shew their construction, by referring to figure 
 1 in Plate 30 which describes the swivel of the forcing Ma- 
 chine ; and which will give a complete idea of what is here 
 intended. From this contruction it will appear evident, that the 
 point A B, (Plate 44) will be always found in the middle, 
 between the two points, of the outer legs of the compasses ; 
 and that whether the question is to take two equal distances 
 from a central point, or to bisect a given line or distance at 
 one operation. The point or style now slides in the two swivels 
 A and E ; but the Instrument might be so constructed, as for 
 
354 
 
 it to follow the rising motion of the middle joint (JE), and thus 
 to keep the three joints in the same horizontal line : but I think 
 a small perpendicular motion of the said style, would be always 
 desirable in the Machine, as a drawing Instrument. 
 
355 
 OF 
 
 A MUSICIAN'S PITCH-FORK, 
 
 With variable Tones. 
 
 L HIS device is shewn, in two positions, at figs 1 and 2 
 of Plate 45. In it's present application, it is intended to 
 produce a whole octave on the diatonic scale : and therefore, 
 the unsupported ends of the fork are just half as long as 
 they would become if the sliding handle A, were drawn to the 
 bottom end of the branches c d. For, again, the fixing screw 
 C, and it's box Z> are fastened to this sliding handle by one or 
 two screws, (Y) so as to be always ready to press the branches 
 against the enclosed slide A B, at whatever place the intended 
 tone may be found. Now, the branches a c, b d, spring out 
 of a common trunk c d, which is pierced with a square hole, 
 exactly fitting this sliding handle AS; and the latter is 
 marked, at proper distances, with lines across it, each of 
 which (placed opposite the mark c d) gives such a length to 
 the remaining branches a b, as to make them sound the note 
 desired. Thus, the line 1, brought to c d, lengthens the 
 branches a b } to (nearly) 53 parts, from 50 at which they are 
 now fixed ; the whole length a c, being 100. This, and the 
 following divisions would, of course, follow any desired tern- 
 perament, according to the will of the tuner : but I have sup- 
 posed them founded on the equi-harmonic scale ; and thus will 
 
356 
 
 the successive intervals to be set off on the slide B A, be as fol- 
 lows : (while the corresponding notes will be those expressed 
 in the table,) 
 
 In the state represented by the figures 1 and 2, the line a J3, 
 is 5000 ; being one half of the whole length a b, c d. 
 
 To form the Sharp 7th. it becomes 5297 the distance c d I, being 297. 
 
 greater 6th. 
 
 5946 
 
 J 2, , 
 
 649, 
 
 ,, 5th. ,, 
 
 6674 
 
 23, , 
 
 728. 
 
 4th. 
 
 7491 
 
 34, . 
 
 817. 
 
 3rd. 
 
 7937 
 
 45, 
 
 446. 
 
 ,? 2nd. 
 
 8909 , 
 
 56, j 
 
 972. 
 
 fundamental note . , 
 
 ,.10000 
 
 6-7, 
 
 1091. 
 
 The above lengths 1 2, 2 3, &c. have been measured off on the 
 slide AB, as nearly as possible, or at least with precision enough 
 to give the idea : and the rest I must leave the detail of, to 
 those musical readers who may feel interested in the subject. 
 
357 
 OF 
 
 AN ESSAY, 
 
 To obtain a Level at Sea. 
 
 I HAVE done right in calling these attempts " essays" : and if 
 I had said " immature attempts," they would have been better 
 designated. Yet, having promised them to my readers, I can- 
 not now withold them, although, from want of opportunity of 
 trial, I can do little more than talk of their supposed properties. 
 
 The first essay, as shewn in fig. 3 of Plate 45, is a mental 
 deduction from a device which I executed in 1801, and 
 brought before the public at the exhibition then given, by the 
 French government, of the produce of national Industrie. It 
 was, nothing more than a pendulum, made with a view to 
 lengthen, considerably, the going of a given clock, without 
 altering the wheels. To that end, the weight or bob, was 
 a heavy bar C D, suspended diagonally on two points A B, 
 placed at a distance from each other, exactly equal to the 
 length of the said bar : and that by the light cross-bars B C 
 and AD, of a length sufficient to make the whole assume a form 
 exactly square : where it may be noted that were this figure 
 longer than high, the curve of vibration would have two points 
 of inflexion, and the bar would not place itself horizontally at 
 last ; and that were it narrower and higher, that curve would 
 
 
 
 ill 
 
358 
 
 assume a form more like, though still distant from, the arc 
 of a circle. In the present case, such was the effect of this dis- 
 position of things, that the centre of gravity of the bar des- 
 cribed, in vibrating, a curve E C D F, the lower form of which, 
 was so near to a horizontal line, that the times of vibration 
 were immensely prolonged ; so much indeed, as to represent a 
 common pendulum of several thousand feet in height ; and 
 to give a proportionate slowness to any mechanism with which it 
 should have been connected. In fact, this line is so minutely 
 different from such horizontal line, that it is wholly included 
 in the thickness of the drawn-line CD : nor becomes visible but 
 near it's two ends C D, when it begins to rise, and then rises 
 faster than that described by a short common pendulum. 
 
 In fine, this curve itself is formed by continually bisecting 
 the line or bar C D, and drawing lines from it's centre of 
 gravity, thus found in one of it's positions, to the same in 
 another position, till the curve E C D, &c. arises from this 
 process. 
 
 It follows, then, from the nature of this curve, (or pair of 
 curves) that the time of vibration of this pendulum is the longer, 
 the shorter the arcs are, in which it vibrates ; and that, when 
 the vibrations have attained a certain length, compared with 
 the height to which the centre of gravity rises, the time be- 
 comes considerably shorter. I shall not now pursue this idea, 
 because it is at once an abstruse question, and at the same time 
 
359 
 
 one of uncertain utility I mean that it's use is problematical as 
 a pendulum: since the time of a vibration depends on it's length^ 
 which cannot easily be determined by any invariable method. 
 I shall, however, add two things on this subject, by way of 
 land mark ; the one, that the balance-wheel of a watch has 
 power enough to drive this pendulum, heavy as it is ; and the 
 other, that I have seen it make (for many hours together) 
 vibrations of half a minute's duration ! In a word, this is one 
 of the subjects, which untoward circumstances have pre- 
 vented me from bringing to maturity but which I owe to 
 my subscribers, and the public, in any, or every state, to 
 which I have brought them. 
 
 I therefore, say nothing more of this Instrument as a pen- 
 dulum : but an inspection of the figure will shew, that it will 
 not be useless as an ELIPSOGRAPH which it clearly is, since the 
 intersection of the bars A D & 7? C ; describes a true Ellipsis. 
 It may be further shewn, that the ends of the moveable bar 
 C D, are the vibrating foci of a second ellipsis, like the 
 first, which rolls under the other, so that the curve itself 
 is that which the centre of one ellipsis a b c would describe, by 
 rolling on the surface of another e b d. But, into these conside- 
 rations I cannot now enter, as my " Century of Inventions" is 
 fast becoming due, and time commands dispatch ; I beg leave, 
 therefore, to pass to the relation this subject seems to bear 
 to a " Marine Level." 
 
 i i i 2 
 
360 
 
 It must, however, be premised, that I scarcely expect either 
 of these methods to be correct enough for astronomical obser- 
 vations ; as among other things, they have the nautical top to 
 contend with : but if I am fortunate enough to have suggested 
 useful methods of procuring relative stability on board a rolling 
 ship, so as to suspend the better, a nice instrument of astro- 
 nomy ; or so to counteract the restless ocean, as to assist 
 the victims of sea -sickness, I shall not entirely have lost my 
 labour. 
 
 My first idea on this subject, is the following : If we had 
 on ship-board, a simple pendulum of several thousand feet 
 high, it appears certain that the oscillations of the ship would 
 be begun and ended, before any single vibration could 
 have been given to such a length of pendulum which 
 therefore, would scarcely vibrate at all : and if the natural time of 
 this compound pendulum (for we are not confined to these small 
 dimensions) were made to be much longer than those of the 
 ship on it's meta-centre, this pendulum would scarcely vibrate at 
 all : because it's several tendencies to take motion from the 
 ship, would extinguish each other before they had had time 
 to produce any common effect. 
 
 Further, this result would probably be assisted by another 
 property belonging to this mechanism : see fig. 4. This 
 diagonal suspension, as repeated at a b c d, fig. 4, is of 
 such a nature, that when it's centres a b, are placed in any 
 
361 
 
 oblique position e f, (say by the rolling of a ship) the suspended 
 bar c d, immediately takes a position of opposite obliquity g h, 
 pointing upward towards i, just as much as the line e b points 
 downward ; while the middle line k I remains level whether 
 caused by the slides k I, or the single slide m. 
 
 I dare not assert any thing respecting the form this principle 
 should assume, in order to produce the most useful effects ; but 
 it appears that the principal weight of the apparatus should be 
 placed in the centre of gravity of the under bar c d. It would 
 occur, of course, to every mechanician applying this System 
 to real use, that in this fig. 4, we have only provided for one 
 motion of the ship, the rolling motion : and that, in conse- 
 quence, this System should be suspended in another similar 
 one, acting longitudinally, so as to provide for the pitching 
 motions of the vessel. In a word, I confess, with regret, that 
 I leave much to do, by way of bringing this idea to maturity 
 it being at this late hour, more than doubtful, whether I shall 
 myself ever be able to resume the subject at sea, where alone 
 it can be duly tried. 
 
362 
 
 OF 
 
 A SECOND ESSAY, 
 
 
 
 To procure a Marine Level. 
 
 J. HIS would seem to be a simpler process than the former : 
 but how far it may go beyond it in effect, I cannot say 
 having never had it in my power to try either of these ideas on 
 ship-board. I therefore merely present them to my readers, as 
 themes for future thought and experiment. 
 
 Plate 45, fig. 5 represents this System which is founded 
 on the idea of deadening oscillatory motions at sea, by con- 
 necting the bodies to be thus guarded, with a stream of flowing 
 liquid, the horizontal motions of which must be subject to laws 
 very different from those which rule vibrating bodies merely 
 suspended. 
 
 The fluid used in this Machine (as oil, water, mercury, &c.) 
 is to be pumped up by appropriate mechanism, from the vessel 
 into which it flows at oc, into a vessel placed a little above % ; 
 and to be let out by the cock y , through a kind of strainer s, 
 of sufficient collective area to supply, with ease, the descending 
 column C. The vessel and tube C D are made as thin and 
 light as possible : and the upper part, which is spherical, is 
 inclosed in and suspended by the universal joint a b c, like 
 
3* 
 
 those used to suspend other bodies, as a compass, &c. More- 
 over, the areas, at different heights, of the tube C Z), are 
 made in the inverse ratio of the velocities of the spouting fluid, 
 at each given depth so as to leave it but little tendency to press 
 either outward or inward, while thus obeying the law of gravity. 
 By these means-, then, I think no vibrating motion will be excited 
 in the falling column : but that the liquid will continue to flow 
 perpendicularly, so as to preserve (nearly) the quietude of the 
 vessel C .D, and of any mirror or instrument it may be wished 
 to keep in a given position, by connecting it with the perpen- 
 dicular line thus obtained. 
 
 I repeat, however, that I know not how far these methods 
 may go towards obtaining an artificial horizon, for astrono- 
 mical uses. Indeed, I fear they will fall short in this respect 
 but I think them still worth trying, even for these but es- 
 pecially for the purposes to which I have already alluded. 
 And, if success crowns this publication, to the degree I am 
 led to anticipate, I will not always leave so rich a question, 
 in this doubtful predicament. 
 
364 
 
 OF 
 
 A FIRE-ESCAPE, 
 
 On a retarding Principle. 
 
 JL HIS is a recollection from the specification of a Patent 
 which I took out above thirty years ago, and in which I hud- 
 dled together as many objects as a child would like to see in a box 
 of play things. I perhaps acted, then, according to the words of 
 a French proverb " abondance debien ne nuit pas ;" but in so 
 doing, I fell into the charybdis of another French proverb 
 (( qui trop embrasse, mal etreint," (a wide embrace cannot be 
 a strong one) and in so doing, paved the way to much liti- 
 gation which happily did not occur. 
 
 The intention of this Machine, as represented in Plate 
 46, fig. 2, was to retard the fall of any body, or person, sus- 
 pended to it, so as to prevent any concussion on reaching the 
 ground. The means are brought to view in the perspective 
 sketch given of the Machine. It is a kind of jack, inclosed in 
 a case, and supposed to be laid carefully aside in the house 
 represented in fig. 1 of this Plate. The Machine has a barrel, 
 much like that of the jacks used for roasting ; round which a 
 rope is coiled, of sufficient length to reach the ground : and 
 a wheel, connected with this barrel, works in an endless 
 screw, which turns a shaft also like that of a common jack, 
 
365 
 
 but somewhat stronger ; and finally, to this shaft is fixed a small 
 cross piece, carrying, on pins, two weights y z, inclosed in the 
 fixed barrel x ; by the centrifugal force of which enough fric- 
 tion is created, to prevent the acceleration of the falling body 
 whether a person or weight of any kind. 
 
 There is, moreover, a jib a, fig. 1, fixed between some, or all, 
 the windows of the house whose inhabitants it is wished to 
 guard from the danger of fire ; this jib having the property, 
 from the form of it's foot, of taking by the suspension of any 
 weight to it, a position perpendicular to the wall : Insomuch, 
 that by the act of suspending the Machine to the jib' engaging 
 the wrist in the noose n t and perhaps the foot in another loop of 
 the same cord ; a person may safely flee those dangers from 
 fire, of which so many persons become the unhappy victims. 
 
 Since the 46th. Plate was engraved, it has occurred to me, 
 that a method should have been shewn for raising the cord n, 
 (fig. 2) after each descent. This operation might be performed 
 by a handle put on the axis of the Machine, accompanied by 
 a ratchet on the wheel, just like the similar parts of a jack for 
 roasting. But, lest the inmates of a house on fire, should not 
 have presence of mind enough to perform this operation, it 
 might be better to have a spiral spring in the Machine, to be 
 wound up by the descending body, and of force sufficient to 
 raise again the cord after such descent. 
 
 Kkk 
 
366 
 OF 
 
 A SECOND FIRE-ESCAPE, 
 
 By breaking the Fall. 
 
 JL HIS Machine is also shewn in Plate 46, at fig. 1. It con- 
 sists of a large truck, A, to be drawn rapidly to any house on 
 fire, by one or more horses. The carnage or frame part B B, 
 is an open square frame subtended by a first sheet of sack cloth, 
 similar to the sacking of a bed : and on this are laid five, or 
 more, air mattr asses made of sack cloth, and varnished on the 
 inside so as to be nearly air-tight ; I say nearly so, for it is 
 not intended they should form a spring capable of returning 
 any object thrown on them. On the contrary, each of the 
 mattrasses has, at one or both ends, a valve 1, 2, &c. opening 
 outwards, but kept closed by proper springs, so as to determine 
 the pressure at which the air shall escape ; that pressure being 
 carefully graduated, so that the upper mattrass shall give way 
 with ease, the second with greater effort, and the successive 
 ones with progressive difficulty, until the under one remains 
 totally closed, and stops the falling body altogether. By these 
 means, if enough mattrasses are used, and they are duly re- 
 gulated, a person may jump from a house of three or four 
 stories without incurring any danger. As to the length and 
 breadth of this fire-escape, it should be ample enough to give 
 
367 
 
 the sufferers confidence to take the leap, and as small as an 
 easy passage in the principal streets would require. 
 
 One thing must be described in words as the mechanism to 
 which it relates is fixed under the truck ; and could not be 
 seen in this perspective figure. These mattrasses are filled 
 with air by an horizontal air pump, worked by a crank, which 
 the axle itself of the hind wheels of the truck forms : whence, 
 by pinning this axle to either of the hind wheels, the very 
 motion of the carriage, as drawn by the horses, would distend 
 the mattrasses which would thus be ready for use the moment 
 they arrived on the spot ; and moreover, when there, this air 
 could be replenished, after using, by turning this axle, through 
 the wheels, by hand cranks slipped on it's ends at the place 
 of the linch-pins. Or, in fine, this operation might be per- 
 formed by an air pump prepared for it alone, and placed in any 
 convenient part of the Machine. 
 
 Kkk2 
 
368 
 OF 
 
 A ROTATORY CHOCOLATE MILL. 
 
 FIGURES ] *& 2 of Plate 47, exhibit this Machine. It is, merely, 
 an attempt to effect, by power and a rotatory motion, what 
 is done by hand and a vibrating one. To understand this latter, 
 my readers (who have not seen chocolate made) will suppose a 
 metallic rolling-pin, but cylindrical held in both hands, and 
 moved parallel to itself, over a slab of marble, to and from the 
 person employed ; who holds the instrument fast when pushing 
 it from him, and suffers it to turn a little every time he draws 
 it towards him. He thus presents, sometime or other, every 
 particle of the chocolate to every part of the slab and the rol- 
 ler : and this is also done by the Machine shewn in Plate 4/. 
 In figs. 1 and 2, A represents a cylinder of stone or metal, 
 used instead of the aforesaid slab ; andjB a cylinder answering to 
 the roller in question. The latter is placed, by it's axis, on two 
 forks a b, so as to lean, by it's weight, obliquely against the 
 cylinder A-> which it does less or more heavily as the forks, or 
 stands a b, are placed nearer or farther off from the general 
 centre. Further, the motions of these two rollers A and B, 
 are connected by two equal (or nearly equal) wheels c d, by 
 which, when A is turned, B turns also ; but so as to give the 
 surface of the latter much less velocity than that of A, though 
 in the same direction. By these means, all the matter adhering 
 
369 
 
 to both cylinders (for chocolate is made in an unctuous state) 
 is at one time or another, brought into intimate union, and 
 ground together ; and thus is the usual problem resolved, on 
 rotatory principles : nor need we mention the several scrapers, 
 &c. that would be applied to gather up the paste to the middle 
 of the rollers, when spread abroad by the grinding process. 
 
 It may not be useless, just to say here, that this is likewise 
 a good mill for grinding paint or oil colours. 
 
370 
 OF 
 
 A ROTATORY MANGLE. 
 
 1 HAVE insisted, often, on the propriety, mechanically 
 speaking, of doing every thing by rotatory motion ; and thus of 
 avoiding oscillation wherever it is possible. The present 
 Mangle is another attempt to employ that principle. In Plate 
 47, figs. 3 and 4, is an under cylinder, turned as usual by 
 any convenient power. B is a small cylinder not connected 
 with it, nor touching it, being intended merely to receive the 
 weight of the mangle -cylinder D, with the goods rolled on it. 
 C is an upper cylinder as heavy as necessary, or loaden through 
 it's journals or centres, with sufficient weights to make it so. 
 Again, the motions of the two cylinders A and C, take place 
 in such a direction, that any round body placed and pressed 
 between them, would receive from them the same motion ; and 
 thus, a roller of goods, there introduced, will be mangled. 
 This process is so performed, because the cylinders have 
 toothed wheels a, b, on their axes, but which do not geer 
 together : These wheels being connected by an intermediate 
 wheel c 9 which makes them concur in producing the rolling ef- 
 fect above mentioned. But, one thing remains to be observed : 
 the wheels a b, though drawn apparently equal, are not equal. 
 The upper one a, has a tooth or two more than the under so 
 that the motion to the right hand of the under surface of that 
 
371 
 
 cylinder, is not equal to the opposite motion of the cylinder A. 
 And hence, the cloth roller Z>, progresses from Z> towards #, 
 between the cylinders A C, and finally falls out at #, after 
 as many turns of the whole, as the wheels A C have been 
 calculated to give ; and this, is according to the degree of 
 mangling required. 
 
3/2 
 OF 
 
 A MACHINE, 
 
 For driving the SHUTTLE of POWER LOOMS. 
 
 XT is too late to bring this Machine into what might almost be 
 called an overstocked market of ingenuity since many power 
 Looms exist, work, and seem to want nothing to make them 
 perfect. But an idea of forty years standing, founded on a prin- 
 ciple worthy of attention then, may perhaps not be altogether 
 vain at present : Besides I have engaged in my prospectus 
 to present it to the public. I could, indeed, enter into other 
 parts of the Power Loom which I had then begun to execute ; 
 but such is the rapidity with which that Machine is now 
 striding to perfection, that it would be superfluous. I merely 
 then, fulfil my promise. 
 
 On the afore-mentioned occasion, I thought it of impor- 
 tance, that the force employed to throw the shuttle, should be 
 capable of being regulated to any and every degree : and es- 
 specially should be fully prepared to act, before it's action 
 began : and should, then, act independently of every other 
 impulse. 
 
 In fig. 1 of Plate 48, A is a wheel or pulley of about six 
 inches in diameter, from which two cords proceed in opposite 
 
3/3 
 
 directions (.B C) to the pickers, which drive the shuttles _D 
 
 E in the usual method. This pulley runs on an axis going 
 
 through the bottom of the lathe, (or beater) and it might have 
 
 a crank, behind, of a radius equal to a b : but to shew the 
 
 whole in one figure, I suppose the following mechanism to be 
 
 placed in the front of the lathe, and just before the face of this 
 
 wheel or pulley A. c d is a bar turning on the centre c, and 
 
 receiving at it's other end the pressure of a spring e d, which 
 
 in it's turn, is susceptible of different degrees of springiness, 
 
 as regulated by the screw/I On a stud i in the wheel A, is 
 
 put the small bar i d, which forms also a turning joint in the 
 
 bar c d : and thus communicates the effort of the spring to the 
 
 stud z, and thence to the wheel A. Finally, this wheel has 
 
 either under it, on the front side of the lathe, or on it's axis, 
 
 at the back, a pulley, by which it can be turned, by means of 
 
 one or other of the cords brought from the breast beam of the 
 
 loom, round the pullies oc and y, to this wheel a b i, according 
 
 to the dotted lines. Supposing then, one of these cords to be 
 
 tightened by the backward motion of the lathe, it will draw the 
 
 wheel^ about half round : when the stud i will rise to the point 
 
 b, straining the spring to get over the centre: and as soon as it 
 
 is over, the spring will act, and drive the picker and the shuttle 
 
 with the desired speed, independently of any other mover. And it 
 
 is evident, that now the opposite cord x or y, will be tightened 
 
 so that when the lathe shall be again pushed backward to form 
 
 the opening for the shuttle the slide will be carried back over 
 
 the centre a, and re-produce another impulse in a contrary 
 
 direction. 
 
374 
 
 OF 
 
 AN AIR PUMP, 
 
 Or ESSAY towards completing the Vacuum. 
 
 JL HE rapidity with which a vacuum is formed by an Air 
 Pump, depends on the ratio between the contents of the receiver 
 and those of the pump barrels. If the latter be just equal to 
 the contents of the former, (which is a very large proportion) 
 the exhaustion will follow this series : there will remain in the 
 receiver after each stroke, the first contents being 1- 
 
 2? 4 
 
 iT> 32? 64 > I*8> 256) & c - But ^ tne pump barrel contains 
 twice the volume of the receiver then the remaining air, after 
 the strokes, will be ; T , fa ^-, %- 3 , 5^, ~, ~ y Sec. being 
 much nearer to a vacuum than on the former supposition. 
 
 To meet this case, then, I have thought a water pump might 
 be used : that is, a barrel or vessel, much larger than the re- 
 ceiver ; and which by the action of a smaller pump, placed on 
 a lower level, might be alternately filled with water and emptied 
 so as in a few operations to complete the exhaustion, very nearly. 
 
 Thus, in fig. 2 of Plate 48, A is a receiver, B is a large 
 vessel that can be filled with water from the tub C below ; 
 and D is the pump, worked by the handle E. It is a common 
 water pump, (so much the readier adopted, as requiring little 
 
375 
 
 care in the execution.) The question was to make this pump 
 alternately y// and empty the vessel B. Adverting first to the 
 filling, a c are two cocks, having each a side-passage for the 
 water ; and these passages are now so placed, as by working 
 the pump we suck water out of the tub C, and throw it into 
 the vessel B, through the valve b ; by which means all its air 
 is driven out through the lateral valve e. When this is done, 
 the cocks c d (which are so made as to be worked by the same 
 moverj are turned into a new position, which opens the pipe p 
 to the pump Z>, and that q to the returning spout r ; by which 
 means the water is drawn from the vessel B, and thrown into 
 the tub C : so that the air is again drawn out of the receiver 
 A^ through the inverted valve s, into the vessel B, and ano- 
 ther degree of exhaustion occasioned. This being done, the 
 cocks are again put into their present position ; the air ex- 
 pelled by the water through the valve e as before, and a new 
 stroke prepared. It is scarcely needful to add, that if the ves- 
 sel B contained ten times as much volume as the receiver A, 
 the exhaustion of the latter at each emptying of the vessel B 
 would follow this ratio jj-; ^ -^^ 7 &c. thus approaching 
 by rapid degrees to a perfect vacuum. The water, or liquid, 
 used for this purpose would of course be as perfectly purged 
 of air, as possible. 
 
376 
 
 OF 
 
 JL HE principal mechanical merit I conceive this Machine 
 to possess, lies in the facility it gives of taking a stream of 
 water as high, and discharging it as low as possible : and both 
 nearly in the direction in which it naturally flows. Of the ad- 
 vantage it possesses in keeping the water a long time from fall- 
 ing, I shall not now speak, as it would require more discussion 
 than this work comports; and, moreover, the Plate confines us 
 to a somewhat contracted representation, which I hope my 
 readers will excuse. 
 
 Plate 48 fig. 3, A J5 is the section of the wheel, and C D 
 a small portion of it's circumference which shews the form 
 and position of the floats a b c, &c. E is a floor on which the 
 upper water flows, and from which it falls thinly on to the wheel 
 whose motion is purposely made as slow as possible. The 
 water then, occupies one half of the wheel's circumference, 
 falls by a gentle slope and finally leaves the wheel at d, 
 whether it there touches the lower water, or not. This wheel 
 is allowed to be incapable of using to advantage a large stream 
 of water but is doubtless fit to employ a small stream, in the 
 best manner. 
 
377 
 
 OF 
 
 A VESSEL, 
 
 To assist in taking Medicine, fyc. 
 
 I HAVE hesitated a moment to describe this method of 
 helping the weak, in body or mind, to conquer their aver- 
 sion to medicine several persons having threatened me with 
 a larger dose of ridicule than I am prepared to swallow. But 
 surely, if we can only conquer a child's timidity, so as to 
 induce him to take, speedily, what his health requires, we shall 
 not do a thing altogether laughable. We shall, perhaps, pre- 
 serve a beloved child to the solicitude of a mother ! and per- 
 haps a citizen to his country ! If then, some laugh, more 
 will approve ; and 1 therefore continue the promised article. 
 
 Fig. 4 of Plate 48, shews this cup, composed of an inner 
 and an outer vessel : the first to hold the medicine, and the 
 latter a little tea, or other proper liquid to wash it down. The 
 cups have a spout common to both ; but the outer cup retains 
 it's contents as long as the small funnel a, is stopped with the 
 thumb or finger. Thus then, the medicine is first taken, while 
 the liquid is retained in the outer vessel but the thumb being 
 removed, the liquid also flows into the mouth, and in a good 
 measure removes the taste it was wished to disguise. 
 
378 
 OF 
 
 AN AERO-HYDRAULIC MACHINE, 
 
 For raising Water in large quantities. 
 
 art of constructing Mills, or Machines to be driven by 
 the wind, is so well known, that the results are considered as 
 being, very nearly, what a perfect theory would require. It 
 is, therefore, no part of my purpose to discuss either the 
 theory or practice of that art. But I think that a still wider 
 grasp may be taken of this powerful agent, so as to secure a 
 further degree of utility, even while following less closely the 
 abstract principles of mechanical philosophy. I enter then, 
 directly, on the description of another of my wind Machines, 
 in order to give an idea of the means I contemplate for losing 
 the importance of those details in the magnitude of the general 
 effect. 
 
 This Machine (see Plate 49, fig. 1,) is capable of great 
 results merely because it employs, at a small eocpence, a great 
 mass of air in motion ; whether ill or well, is not the question : 
 for as this source of power is almost indefinite, methinks we 
 may draw from it without reserve. The present method of so 
 doing, consists in using a very large sail, (A IT) both to 
 receive the impulse of the wind, and to raise the water. This 
 figure is a section of the Machine in it's length: and it's 
 
379 
 
 width (not represented) is as great as the occasion may require. 
 The sail is here shewn as placed over a lake or other sheet of 
 water which it might be wished to drain, (or which may serve 
 as a mill pond to drive any required Machines, by the water 
 thus raised.) C D is the water in it's lower bed : and E, is a 
 canal on a higher level, into which a large quantity is thrown 
 at each manoeuvre of the Machine, a is the bank of the upper 
 canal, to which is affixed the edge of the canvass, of which 
 a B A d, is a section ; and which might be large to immen- 
 sity. At 1 2 3, &c. is a row of stakes as long as the Machine ; 
 and they are capped transversely with round poles, on which 
 the sail rests when in it's lowest position. In this state, also, 
 the part b of the sail, plunges into the water, which rises 
 above it in the prismatic form, b r s ; a row of valves or clacks, 
 (F) permitting it to rise through them, but preventing it 
 from again falling that way. Thus, at every change, this 
 prism of water, is sure to be replenished; and if we suppose the 
 triangle b r s to have an area of ten square feet, and the prism 
 to be one hundred feet long, the water there contained will 
 be a thousand cubic feet capable, however, of being aug- 
 mented or diminished at pleasure, by slackening or tightening 
 the sail towards A. At d, is the weather -end of this sail, 
 which is supported when at rest, on the surface of the water, 
 by the posts and caps before mentioned. This end d, of the 
 sail is connected with a row of posts C F, placed more or 
 less closely, as the prevailing strength of the wind and the size 
 of the sail may require. The sail is held to these posts by 
 
380 
 
 rolling pulley frames, of which one is seen at g, and is drawn 
 up and down by the rope g h, acting at one end directly on 
 the rolling pulley-frame g y and the other on the sail d, after 
 having passed over a pulley (F) in the post itself: where note, 
 that this effect can be communicated by proper machinery, 
 from any one of these posts (C F) to all collateral ones ; so as 
 to make the manoeuvres general, across the sail, whatever be 
 it's magnitude. 
 
 The following then, is the operation. The wind blows (by 
 supposition) in the direction of the arrows in the figure : and 
 the rolling pulley-frame g is quickly drawn up to g, where the 
 hook i holds it fast. By a necessary consequence the wind 
 fills the sail d c r, and stretches it into the figure d A B a : 
 in doing which it lifts the water r s, and pours it, in all the 
 width of the sail, into the canal JE ; thus raising a thousand 
 cubic feet of water at each stroke. As soon as the water is 
 turned into the canal E, the hook i is pulled outward, and the 
 rolling pulley g is forced down, by the wind itself, to the position 
 k, when the wind blowing over the sail, will give it a bent form, 
 (k c a) and soon bring the sail into it's present position on the 
 posts 1 2, &c. when water will be again admitted by the 
 valves at /&, and another stroke of the Machine be prepared. 
 
 The above contains the basis of this idea. I do not expect 
 it will obtain at once universal assent : But if I knew the se- 
 veral grounds of objection, I am persuaded the greatest number 
 
381 
 
 of them could be removed. The first I anticipate, is the 
 difficulty of turning this Machine to the several winds that 
 may blow over it. To this objection I would reply, that in 
 such a case, the canal E, should surround an area made large 
 enough for the sail, of some polygonal form, say an octagon, 
 to different sides of which the stretching cords of the sail should 
 be carried, so as to catch the prevailing winds but the di- 
 rection of which need not be followed to a nicety ; since an 
 obliquity of a few degrees would not prevent the effect. 
 
 It might be added, that it is not indispensable that the canal 
 JE should be stationary. Made of wood, or metal, it might 
 turn round a fixed centre, and be braced into the necessary 
 positions with ropes when the posts only (C-F) would have 
 to be removed, or quitted for others duly placed. These ideas 
 are connected with immense effects ; and cannot, therefore, 
 be lightly disposed of: they both deserve and require serious 
 attention. 
 
 M m m 
 
382 
 OF 
 
 ANOTHER WIND MACHINE, 
 
 Furnishing immense Powers. 
 
 JL HIS is the last of those conceptions I shall now bring 
 forward, for making more than a common use of the WIND as 
 a first-mover of Machinery. Horizontal windmills are well 
 known ; and this is a horizontal windmill yet not like those 
 already in use : for, here, the sails, very large and numerous, 
 are placed on a boat in the form of a ring, which thus moves 
 through the water without any other resistance than that 
 arising from the asperities of it's surface. 
 
 In Plate 49, fig. 3, B B is a section of the Vessel, placed 
 in a circular canal Z), into which the lower water flows through 
 proper arches (C C) in the banks. The vessel is rigged with 
 several narrow horizontal sails, stretched on ropes between 
 the oblique masts a b, c d ; and so placed, that the sails (being 
 a little wider than the interval between the ropes) can open 
 in one direction, but not in the other ; and they are shewn 
 open at c d, and shut at a b, in the figure. This, therefore, 
 is a mill, that takes all winds ; and although it's uses might be 
 various, we shall finish it's description as adapted to raise 
 water by the centrifugal force. As before hinted, the canal 
 D D is circular ; and has a bank, sloping outward, with a 
 
383 
 
 canal (J) on it's top. When, therefore, the wind blows, 
 the ring boat J5 (held to the centre by the ropes f g) revolves 
 around it ; and by one or more water drags (Ji) which it 
 carries, collects the water on and up the bank, and finally 
 drives it into the canal E, from which it flows in any destined 
 direction. If for draining watery lands, it will be done ra- 
 pidly ; if for irrigating, it will be done abundantly : if, in fine, 
 for driving any mill with the water thus raised, the machinery 
 will be very efficient, as working with ten or twenty times as 
 much sail, as any other windmill can carry. I add, merely 
 on this occasion, that the sails here mentioned, might be 
 placed obliquely, instead of straight across the ring vessel ; 
 (see the plan in fig. 2 of this Plate at E F) from which dis- 
 position, nearly all the advantages of the vertical mill might 
 be transferred to the horizontal ; and with this remark I leave 
 the present interesting subject to the studious and candid 
 reader. 
 
 M m m2 
 
384 
 OF 
 
 A CENTRIFUGAL MIRROR, 
 
 To collect Solar heat. 
 
 JM.Y fiftieth and last Plate contains this idea: It is not in- 
 tended to vie with the usual mirror, in correctness of form, or 
 intensity of local effect but to offer, by the largeness of it's 
 dimensions, some properties which better mirrors cannot pre- 
 sent. It is intended to pave the way for the use of the Sun's 
 rays in Engines of Power. For this purpose, however, it must 
 probably be transported to some tropical climate, where " a 
 cloudless sun" diffuses it's rays more constantly, and less ob- 
 liquely, than in our northern climes. 
 
 This is the more necessary here, because this Mirror can 
 only be used in a horizontal position, and is in fact a fluid 
 Mirror. Fig. 1, shews it mounted on a steady frame A B, 
 and having a strong axis on which it can be turned, faster or 
 slower, according to it's dimensions ; and it may or may not 
 be floated on water, to lessen the stress on the axis. The 
 Mirror, properly speaking, is composed of mercury contained 
 in the revolving vessel C D, whose motion should be given by 
 proper machinery in the most uniform manner possible. The 
 mercury, thus turned, acquires a concave surface, , by c; 
 and receiving the parallel rays d c, e b, and fa, collects them 
 
385 
 
 into the focus .F; in, or near which, is placed the vessel where 
 the effect is to hecome useful, and which of course is moveahle 
 so as to follow the sun's motion. Those of my readers who have 
 
 m 
 
 seen the machines used for fixing the sun's image in the solar 
 microscope, will be at no loss to conceive how our present focal 
 station must be moved to adapt it to SL fixed mirror. I shall only 
 add further, that it is not necessarily an exact movement that 
 is here wanted ; since the vessel to be heated would have 
 dimensions somewhat large, and the focus itself be only 
 brought to a moderate degree of precision. In a word, the 
 utmost heat wanted would be, what could be usefully employed 
 in heating water. It remains then to be observed, that the 
 source of power, in this Machine, is magnitude of parts, more 
 than precision of form: yet it may be mentioned, that the form 
 we thus procure in the revolving mercury, is a solid of revo- 
 lution, having the logarithmic curve (a, b c) for it's section 
 a curve, which in fact, comes indefinitely near to the parabolic 
 figure which would be required, if greater precision were at- 
 tempted. We finish then, by observing, that the bottom it- 
 self of the revolving vessel might be made concave, (like the 
 dotted line under that a b c) in order to avoid the necessity of 
 using a large quantity of mercury, to form the reflecting sur- 
 face. 
 
386 
 OF 
 
 A SECOND MIRROR, 
 
 For collecting the Sun's rays. 
 
 J[ HIS Mirror seems superior to the former, as depending 
 on fixed materials. It likewise, produces the desired effect, 
 by offering a very large surface to the sun, and directing the 
 rays to a focus, nearly enough to give the heat required for 
 water, as before mentioned. 
 
 To do this, a frame A (Plate 50, fig. 2) holds the Mirror ; 
 and this frame has a horizontal motion round the post J5, some- 
 thing like a common windmill. In this frame and on two 
 horizontal trunnions, turns the Mirror C D : and one or both 
 these trunnions are hollow, to admit of a process we shall 
 shortly mention. This Mirror itself is composed of an air-tight 
 ring C Z>, of a width proportionate to the diameter adopted ; 
 and on which are fixed two heads, much like those of a tam- 
 bourine, (or the under head might be made of some metallic 
 substance). The head a b c, is made of a fine texture, duly 
 prepared and varnished till it becomes air tight, and then there 
 are stuck to it, a number of small hexagonal looking-glasses or 
 mirrors of any kind, (see fig. 7) which thus fill up the whole 
 space, and prepare the Mirror for the intended change of form. 
 
387 
 
 The method of giving this form, consists in exhausting, more 
 or less, this tambourine of air, when, by the pressure of the at- 
 mosphere, the heads will take the form a b c, that is a spheri- 
 cally concave form fit to reflect the sun's rays as correctly as 
 this our object requires ; and thus may some thousand small 
 images of the sun be brought to fall on the same spot, and an 
 immense heat be occasioned. The accounts we have of the 
 destruction of the Roman fleet by the united mirrors of Archi- 
 medes, makes this process appear the more feasible as what- 
 ever were the methods of uniting the foci of his mirrors, a 
 similar effect may be expected from this simple process. 
 
 My readers will perceive that this Machine has the ad- 
 vantages of the universal joint, by which it can be directed to 
 the sun in every position ; and even made to fix his ardours on 
 any immoveable spot for a good length of time. The persons to 
 whom I particularly address these ideas, will require no further 
 details to conceive the less obvious circumstances of this In- 
 vention. In general, we want no effect that requires optical 
 precision: but if we did, it could be obtained to a good degree, 
 by methods similar to these. 
 
 I shall only add here, that this fig. 2 is given as a section 
 because intended to represent a parallelogram, as well as a 
 solid of revolution : and thus (with proper mirrors) to make 
 what now appears a sherical focus, a linear one fit to heat a 
 
388 
 
 cylindrical vessel with it's contents ; and thereby draw power 
 from the sun's heat, without running expense. I am serious 
 when I say, that we can thus, practically, collect the solar 
 rays which fall on many hundred square feet of surface ; and 
 produce by them, at any desired distance, effects to which 
 those obtained from modern burning mirrors, are but as sparks 
 to a blaze. 
 
389 
 OF 
 
 AN ENGRAVING MACHINE, 
 
 For large Patterns. 
 
 JL HIS Machine supposes at once a new kind of engraving, and 
 admits of patterns of very large dimensions. This kind of engrav- 
 ing will be best understood by persons acquainted with figure- 
 weaving; and especially with the manner of mounting the looms' 
 for that purpose. In that System, (see Plate 50, fig. 8) the 
 patterns are drawn on ruled paper divided into squares ; and each 
 of these squares represents a point in the texture, composed of 
 one or more threads each way ; insomuch that whenever that 
 square has any desired colour in it on the pattern, it's threads 
 are taken by the person who prepares the loom ; and they are 
 missed in every case where nothing appears in that square, or 
 a colour not then wanted. Now, whatever be the dimensions 
 of these elementary points 011 the loom, they may be re- 
 presented by squares of any convenient size on the pattern : 
 only remembering that the smaller they are, in reality, the 
 better will be the delineation. Thus in carpeting, for example, 
 an element of this kind may be a square of one tenth of an inch 
 and more ; while one on a ribbon or a piece of silk, is often not 
 the hundredth part. And therefore, the perfection of this en- 
 graving depends on the fineness of the points of which the figures 
 are composed. For, in a word, this System proceeds on the 
 
 N n n 
 
39U 
 
 same principle. When any part of a line requires a dot or 
 mark to be made, the Machine strikes a blow there; and 
 when no impression is to be made, the Machine (by means 
 that will be shewn) suffers the cylinder to pass that place with- 
 out striking. The means of regulating this is committed to work- 
 men who merely know how to read off the pattern in it's length, 
 as it is now read off -in it's width by the weaver. To describe 
 the construction of the Machine, (as exhibited in figs. 3 and 4 
 of Plate 50) A is the cylinder to be engraved ; and B is a 
 worm-wheel fixed to it's mandril, and destined to turn it. 
 This it does, slowly, by the endless screw , as turned by 
 proper straps on the fast and loose pullies h c, (figs. 3 and 4). 
 C shews a second wheel, concentric with that B, but running 
 loose on it's axis, which is a pin fitted into the end of the man- 
 dril. This wheel, when the threads of the screw a are fine, 
 requires a motion more rapid than the wheel B to give which 
 motion by means of the latter, we use a pair of multiplying 
 wheels d, which geer, one in the larger bevil wheel cut near 
 the edge of the wheel 3 ; and the other in a smaller bevil 
 wheel cut or fixed on the inner face of the wheel C and 
 whence this latter wheel receives a velocity of about ten times 
 the speed of B. The use of this wheel C, is to carry, across 
 the Machine, certain bars, of wood or metal, shewn in figs. 
 5 and 6, whose function is to carry short pins or studs 1, 2, 
 3, 4, &c. for the purpose of determining the places where the 
 punch is to act, and where it is not. To this end, g h is a 
 frame, which is raised by a cam or tappet i, fixed in the 
 
391 
 
 endless screw a, once every turn ; and that through the me- 
 dium of the little tumbler i ef, by which is finally determined 
 whether the stroke shall take place or not for m being a 
 section of the stud bar of figs. 5 and 6, it's pins, when they 
 ocdur, raise the end f of the bent lever f e i ; and when 
 there is no pin or stud in m, this lever is not raised, and 
 the point i, does not come near enough to the cam to be 
 laid hold of, in which case no stroke is given. This then, is 
 so whenever the studs fail in the bar m ; and these fail when- 
 ever the pattern-reader has said to the stud-setter, miss : and 
 they occur whenever he has said take both which cases 
 happen more or less often according to the state of the squares 
 in the pattern. 
 
 To be a little more particular : in fig. 5 we see a part of the 
 wheel C of fig. 3, and also a part of the stud bars m m, which 
 geer in the wheel C, and which being conducted by the guides 
 n, follow the motion of that wheel, presenting at f 9 (fig. 3) 
 a stud to raise the lever f e, whenever the pattern requires it. 
 It may be mentioned, that these studs act obliquely on the wing 
 f of this lever, and thus raise it as they pass under it. And 
 further, these stud bars are made and fitted to each other in 
 the manner shewn at fig. 6. There is a geering tooth under 
 every stud hole, and the last stud hole of a given bar has, fixed 
 in it, a thin tube a, into which the stud enters the same way as 
 in any other place : but this tube whether studded or not serves 
 to lay hold of the succeeding bar b, by it's first hole so, in fine, 
 
 N n n 2 % 
 
392 
 
 as to make the bars endless ; the attendant having nothing 
 else to do than to hook them to each other as the wheel C 
 draws them in. 
 
 Thus then, are the strokes of the hammer frame, g h, 
 conformed to the pattern : for these bars have been studded 
 before hand by one or more readers and setters ; and it is a 
 merely mechanical process to put them in while the Machine 
 moves: from which, by the bye, they fall out after the pas- 
 sage into a proper box, and the studs out of them, to be com- 
 posed again from the succeeding figures of the pattern. A 
 dozen or two of these bars might be prepared at any time and 
 place, and to any pattern, which they will thus transfer to 
 a cylinder at any desired moment, without the further pre- 
 paration of dies, punches, mills, &c. as used in other Ma- 
 chines. N. B. The strength of the blows thus given by the 
 hammer frame g h, is lessened or augmented by the position of 
 the point i fixed to the bent lever i ef, and which makes that 
 lift higher or lower as required which is a mean of shading 
 offered by this Machine. But to mention it's other properties, 
 the endless screw a, (figs. 3 and 4) carries another endless 
 screw o, more or less fine, which turns at the same time the 
 wheel p, and, by that, the long screws s, whose office it is to 
 shift, slowly, the punch carriers k I, along the Machine, from 
 A:, by /, towards s. And here an observation occurs: this can 
 only be so, when the pattern permits the action of the punches 
 k or /, to take place spirally on the cylinder ; that is, when 
 
393 
 
 the sketches are distinct enough not to shew the anomaly that 
 would occur were a straight pattern thus transferred to a set 
 of spiral lines. But should it be desirable to engrave pat- 
 terns so correct as to require an exact parallel motion round 
 the cylinder, then the motion of this screw must not be con- 
 tinual but must intermit and be resumed, at every beginning 
 of a new line round the cylinder. I hope, I make myself 
 understood : a pattern drawn on squares, produces lines all 
 parallel to the first ; while the spiral motion of the punch 
 causes a slight deviation which, in a word, can either be suffered 
 or avoided. At all events, this deviation is so much the smaller 
 as the punch motion is slower in both directions ; and, in fine 
 patterns, must be very small. One remark will close this part 
 of the subject : although a fine pattern, requires a great num- 
 ber of blows, and thus a certain expence of time, each blow 
 can be so much the lighter and more frequent ; so as to com- 
 pensate, in some degree, for this cause of delay. I add, that 
 the levers shewn above and around fig. 6, are intended to lift 
 the hammer frame g h, equally at both ends : while the screw 
 Z regulates the depth to which it is permitted to fall. 
 
 I observe, finally, that, according to the size of the in- 
 tended pattern, there are more or fewer of the punch bearers 
 k I, connected, by their nuts, with the screw s s; each of 
 which thus engraves it's sketch, similar to the collateral ones ; 
 and that were it wished to make one pattern of the whole 
 length and circumference of the cylinder, a single punch 
 
394 
 
 bearer would be required since nothing else limits the extent 
 of a pattern engraved by this Machine. 
 
 Thus have I gone through my proposed "Century of Inven- 
 tions," for every imperfection in which I beg the indulgence of 
 my numerous readers. And here I can truly say I have neglected 
 nothing although the precarious state of my health may have 
 sometimes veiled the evidence of my descriptions. On the other 
 hand, I did not even attempt many of the lesser details of ex- 
 ecution ; as I wrote for those to whom they would have been 
 superfluous : but as to the objects themselves, I believe there 
 is not one that is without the pale of practical utility. In a 
 word, many of the subjects have been frequently executed, 
 and are in daily use : and as to those which remain to be tried, 
 I engage, if called on, to give them useful existence. And 
 the better to convince candid minds of the serious attention 
 I have paid to these subjects, I shall add the scales on which 
 they have been executed, or to which they are drawn those 
 scales expressed by a fraction, shewing what proportion the 
 figures bear to the reality. Thus the scale of one inch to a 
 foot will be expressed by the fraction -^ ; that of two inches 
 to a foot, by _., & c< that is, the figures, in these cases, will 
 be (nearly) I O r of the size of the Machines. This premised 
 and also that we shall observe the alphabetical order, the fol- 
 lowing is the 
 
TABLE OF CONTENTS. 
 
 No. Scale Page. 
 
 1 ADDING MACHINE ; or Machine to cast up large Sums . . . . and 1 343 
 
 2 Air Pump : Essay to complete the Vacuum ITT 374 
 
 3 Barrel Spring, to lengthen the going of Clocks, &c. 1 2 
 
 4 Boats (serpentine) for lessening the expence of traction, &c ^ 137 
 
 5 Bobbin or Laces, (Machine for making) covering Whips, &c. . . circa. 284 
 
 6 Bowking Machine, for Bleachers .. .. -^ 299 
 
 7 Bucket or Persian Wheels, (a combination of) to raise Water . . . . -fa 172 
 
 8 Canals (open) as hydraulic Machines . . . . circa. ^ T 307 
 
 9 Canter, or inclined plane for Draymen TT 72 
 
 10 Chain to act equably on my Wheels circa. 1 . 135 
 
 1 1 Chocolate Mill (rotatory) -^ 368 
 
 12 Cocks (equilibrium) to avoid leakage, &c. ad. lib. 153 
 
 13 Colour Mill, for Calico Printers T V 175 
 
 1 4 Compasses (bisecting) 353 
 
 15 Cotton-Machine for batting or bowing circa. ^ 290 
 
 16 Crane (rewarded by the Society of Arts) -^ 57 
 
 1 7 Crank, epicycloidal j or parallel motion (rewarded by Bonaparte) . . & -rr 30 
 
 18 Dash, or Wash Wheel, acting with greater rapidity than usual .. ^ 271 
 
 1 9 Differential Wheels, for gaining great power ^. 54 
 
 20 Doffing Machine, to take cylinders from their mandrels -- 243 
 
 21 Draw Bench, for my twisted Pinions ?- is- 133 
 
 22 Dynamometer, for measuring power in motion 4. 15 
 
 23 a second kind for do j. 1 77 
 
 24 Engine, for cutting my Patent Wheels V. text, -f J^il 
 
 25 Engine, for cutting large bevil Wheels and Models | ^ 263 
 
CONTENTS. 
 
 No. 
 
 Scale. Page. 
 
 26 Engraving Machine, being an important application of my Cog or 
 Toothed Wheels ... . 
 
 T and-rV 
 
 TT 
 -BTT 
 
 ad. lib. 
 
 317 
 389 
 280 
 78 
 166 
 364 
 366 
 311 
 315 
 296 
 215 
 144 
 150 
 79 
 212 
 53 
 217 
 203 
 277 
 230 
 155 
 158 
 305 
 251 
 377 
 370 
 357 
 362 
 83 
 384 
 386 
 76 
 
 27 Engraving Machine, of a new kind, for large patterns 
 28 Essay to derive power from expanding solids 
 
 
 1 
 
 -g- 
 ad. lib, 
 
 
 
 
 TT 
 
 i- 
 
 snr 
 
 ad. lib. 
 
 34 - (watch Engine always ready for) 
 
 35 Flax (Machine for breaking rapidly) 
 
 
 
 ad. lib. 
 
 
 ad. lib. 
 
 39 Grating or cutting Green Roots, &c. (Machine for) . . 
 
 circa. -- 
 ad. lib. 
 
 4 1 Horse Wheel, (inclined) to save room and gain speed 
 
 42 _. (reciprocating) for Mangles &c 
 
 cV 
 
 i 
 
 3TT 
 
 ad. lib. 
 
 
 44 Lamp (hydraulic) for the table 
 
 TT 
 
 Trr 
 ad. lib. 
 
 45 Lithographic, or Copper-plate Press, with curious and useful propertie 
 46 Machine to communicate and suspend Motion 
 
 
 2 
 
 ad. lib. 
 
 48 for clearing turbid Liquors 
 
 
 ad. lib. 
 
 T 
 IT 
 
 circa, -p 1 
 ad. lib. 
 1 
 ad. lib. 
 ad. lib. 
 ad. lib. 
 
 50 to assist in taking Medicine . ' 
 
 5 1 Mangle, -perpetual or rotatory . . . . . . . . ... 
 
 52 Marine Level (essay on a) . . 
 
 53 ^ (other essay on a) 
 
 54 Micrometer, to measure minute spaces 
 
 55 Mirror, (centrifugal) to collect the Solar rays 
 
 
 57 Mover, bv dropping: weights 
 
CONTENTS. 
 
 No. Scale. Page. 
 
 58 Nails (Machine for moulding) rV 200 
 
 59 (Machine for forging) -rw 226 
 
 60 Parallel Motion (double) for heavy Steam Engines ad. lib. 338 
 
 6 1 Pencyclograph ; or instrument for drawing portions of large circles, 
 
 and finding their centres by inspection . . , ad. lib, 51 
 
 62 Peristaltic Machine, for raising water 172 
 
 63 Pitch Fork for Musicians, with variable tones circa. 1 355 
 
 64 Power Wheel, by heated Air, &c ad. lib. 43 
 
 65 Press, direct and differential (power as 52000 to 1) ad. lib. 66 
 
 66 Press (excentric bar) power indefinite ad. lib. 174 
 
 67 Printing Machine (two coloured) iV 301 
 
 68 Protracting Motion (Machine for) , 3 ^9 
 
 69 Pullies (my Patent) much improved . . i- -rV 33 
 
 70 Pump (equable) proposed 1 794, for the Machine of Marly .... * 45 
 
 7 1 portable, worked by the hands and feet TTT 35 1 
 
 72 Punch Machine, for Engravers . , . . . . 293 
 
 73 Machine (differential) for ditto circa. -f 196 
 
 74 rotatory, for my Engraving Machine .. .. .. & 349 
 
 75 Reciprocating or long Parallel Motion ad. lib. 237 
 
 76 Reflector, for Light Houses, &c. ad. lib. 234 
 
 77 Regulator (not centrifugal) for Wind and Water Mills, Steam 
 
 Engines, &c 223 
 
 78 Retrographic Machine, for Engravers ad. lib. 1 64 
 
 79 Rotato-gyratory Churn ^ 210 
 
 80 Screw, with greatly diminished friction ad. lib. 81 
 
 8 1 Screws (Machine for forging) -j. 1 60 
 
 82 Spinning Machines (my Patent) circa, -fa 329 
 
 83 adapted chiefly to Wool T V 334 
 
 84 Spring, to keep a door closed yet open easily .. .. ad. lib. 131 
 
 85 Steelyard (differential) of great power g 162 
 
 86 Syphon (mechanical) to expel part of the Water at the highest point ad. lib. 240 
 
 87 Tallow (Machine for cutting and trying ^ 245 
 
 88 Tea Table (mechanical assistant for) 228 
 
 O O O 
 
CONTENTS. 
 
 No. 
 
 89 Valves (slide) Machine for working 
 
 90 Ventilator, rotatory, yet by pressure 
 
 91 Vessel (expanding) for Pumps, Steam Engines, &c 
 
 92 Washing Apparatus, for Hospitals, &c 
 
 93 Water Wheel (horizontal) probably the best of the impulsive kind 
 
 94 The same, for high falls 
 
 95 Water Wheel (inclined) using the weight of the water 
 
 96 Water (aero-hydraulic Machine for raising) 
 
 97 Weaving by Power (manner of driving the shuttle, executed A. D. 1780 
 
 98 Wedge Machine (perpetual) . . 
 
 99 WHEELS (my System of Cog or Toothed) .. .. . .' .. 
 
 J 00 Windmill of double power 
 
 Scale, 
 ad. lib. 
 
 TT 
 
 ad. lib. 
 ad. lib. 
 
 TTT 
 
 ib. 
 ad. lib. 
 
 alldiinen 
 
 sions 
 
 age- 
 255 
 170 
 219 
 247 
 326 
 326 
 376 
 292 
 372 
 74 
 90 
 313 
 
 ERRATA. 
 
 Page. 
 1, line 
 
 4, 
 
 10, 
 
 15, 
 
 15, 
 
 42, 
 
 43, 
 49, 
 70, 
 
 100, 
 
 102, 
 
 126, 
 
 126, 
 
 129, 
 
 164, 
 
 188, 
 
 196, 
 
 27, after System, read of. 
 27, for them, read it. 
 16, for vestuble, read vestibule. 
 10, for parralel, read parallel. 
 13, after centre, read of. 
 
 7, after was, dele on. 
 
 1, for Plate 2, read Plate 8. 
 
 1, after A, read Fig. 4. 
 
 7, for ionical, read conical. 
 
 2, after A C for :, read : : 
 
 16, for , read [line 
 
 a a 
 
 4, for on it's surface, read at it's pitch 
 
 17, for it's height fg, read the length 
 required. 
 
 16, for 2 inches, read 4 inches. 
 
 10, for other two cases in C & E, read 
 in other two cases C & E. 
 
 17, after b C twice, for :, read : : 
 20, for fig. 2, read Fig. 4. 
 
 Page. 
 200, 
 203, 
 208, 
 209, 
 246, 
 272, 
 273, 
 28T, 
 289, 
 294, 
 311, 
 335, 
 340, 
 350, 
 357, 
 374, 
 375, 
 387, 
 
 8, for Plate 25, read Plate 24. 
 
 11, after heat, read for. 
 
 6, for is, read are. 
 
 8, for arrangements, read arrangement 
 19, after which, read last. 
 23, for wheel, read bevil wheel. 
 21, for axis, read axes. 
 19, for z', read z. 
 
 \, after down, read twisted. 
 
 7, for two, read too. 
 
 8, for carried, read used. 
 10, for bobbin, read bobbins. 
 
 8, for edged formed, read wedge formed 
 
 8, for Fig. 3, read Fig. 6. 
 18, for ligbt, read double. 
 
 12, after ^, read, ^ T . ^. -j 
 
 for r 46 4 i > read -nrrr 
 
 9, for makes, read make. 
 
 &c. 
 
 * # * If, in the following List of Names, it has been thought just to mark those of the first 
 promoters of this Work, it has not been to lessen the Author's obligations to the rest who, almost 
 uniformly, have given him their Names with the same spontaneous kindness, and thus ensured his, 
 \asting gratitude. 
 
ALPHABETICAL LIST OF SUBSCRIBERS. 
 
 ABEL, S. Bury 
 
 Addison, G. W. Huddersfield 
 
 Adshead, James, Stayley Bridge 
 
 Agnew, Robert M. D. Manchester 
 
 Ainger, A. London. 
 
 Ainsworth, G. Stayley Bridge 
 
 Ains worth. Richard Bolton 
 
 Akroyd, James Halifax 
 
 Akroyd, Jonathan Do. 
 
 Allen, T. & Sons, Huddersfield 
 
 Andrew, James Manchester 
 
 Andrew, Thomas Do. 
 
 Antrobus, P. & Nephew, Bollington 
 
 Appleton, Ogden & Co. Manchester 
 
 Appleton, Plant & Co. Do. 
 
 Armi stead, J. & J. Leeds 
 
 Armitage, Cyrus Ashton 
 
 Ash ton, Benjamin Hyde 
 
 Ashton, George Manchester 
 
 Ashtou, James Hyde. 
 
 Ashton, John Junr. Do. 
 
 Ashton, Joseph Do. 
 
 Ashton, Robert Do. 
 
 Ashton, Samuel Jun. Do. 
 
 Ashwell, James Nottingham 
 
 Aston, William Birmingham 
 
 Atkinson, George Burnley 
 
 Atkinson, Joseph Manchester 
 
 Atkinson, Thomas Do. 
 
 Axon, Charles Stockport 
 
 Aydon, Isaac Wakefield 
 
 Babbage, 
 Bailey, 
 
 F. R. S. London 
 
 - Halifax 
 
 Bailey, William Holborn, London. 
 Baird, J. & R. Glasgow. 
 Baldwin, J. & J. Halifax. 
 Barclay, John & Co. Paisley. 
 Barge, John & Co. Manchester. 
 
 Barker, Do. 
 
 Barnes, John London. 
 Bartholomew, J. & Co. Glasgow. 
 Barton, H. Manchester 
 Bassett, Thomas Bury 
 Bates, John Bradford 
 
 Bayley, Abel Stayley Bridge 
 Beaumont, Thomas Huddersfield 
 Beckton, Joseph Manchester 
 Beecroft, Heath & Co. Kirkstall 
 Beeston, Thomas Leeds 
 Beilby & Knotts, Birmingham, 3 Copies 
 Bellhouse, David Manchester 
 
 Bennet, H. M. Dock Yard, Chathan 
 
 Bentley, Richard Bolton 
 
 Berthonneau, Paris 
 
 Be van, R. Wigan 
 
 Bewley, Manchester 
 
 Binns, A. Stockport 
 Binyon, A. Manchester 
 
 Birley, Captain H. H. Do. 
 Birley, Richard Do. 
 
 Birtles, Do. 
 
 Blackie and Pollock, Glasgow 
 
 Bonsall, Thomas London 
 
 Booth and Co. Park Iron Works, Sheffield 
 
 Booth, John Manchester 
 
 Booth, George Stockport 
 
 Bowes and Kilham, Leeds 
 
 Bowler, James Manchester 
 
 Bowman, James Do. 
 
 Bradbury, J. L. Do. 
 
 Bradley, J. Warwick 
 
 Braithwaite, F. and J. London 
 
 Bramah, Francis Do. 
 
 Bramley, R. Leeds 
 
 Bransome, Manchester 
 
 Branthwaite, James Do. 
 Brearley, James Bolton 
 Briarley, Benj. Blackburn 
 Briden, John Birmingham 
 Bridson, Ridgway Bolton 
 
 Brindley, Rochester 
 
 Brook, Jonas and Brothers Meltham 
 Brooke, John Shepley Hall 
 Brooke, John and Sons Huddersfield 
 
 Brooke, Dewsbury 
 
 Brooks, S. R. American Consul, Manchester 
 Broom, Sons and Home, Kidderminster 
 Brotherton, J. Salford 
 Brown, Baldwin L.L.D. London 
 
SUBSCRIBERS' NAMES. 
 
 Brown, S. H. Halifax 
 Brown, Thomas Barnsley 
 Brown, Thomas Manchester 
 Buchan, Laurence Do. 
 Buchanan, A. Glasgow 
 Buckley, John Todmorden 
 Burford, D. and Co. London 
 Burn, John Manchester 
 Burton, George Middleton 
 Burton, John Warwick 
 Bury, James Manchester 
 Bury, John Pendle-hill 
 Bury, Thomas London 
 Bury, Thomas Salford 
 Busk, R. Leeds 
 Butterworth, Thomas Oldham 
 
 Carruthers, John Manchester 
 Carter, Benjamin Huddersjield 
 Carter, John Elland 
 Cartledge, Joseph and Sons Halifax 
 Casey, Thomas London 
 Cawood, John Leeds 
 Chadwick, William Oldham 
 Challinor, Thomas Manchester 
 Chapman, Samuel Ashton 
 Chappe", Paul Manchester 
 Cheetham, Daniel Stockport 
 Cheetham, John Ditto 
 
 Cheetham, Joseph Ditto 
 Cheetham, Josiah Ditto 
 Church, William L. L. D. London 
 Clare, Peter Manchester 
 Clark, John Jun. and Co. Glasgow 
 Clark, Richard Shalford, Surrey 
 Clayton, D. Poynton 
 
 Clement, Paris 
 
 Clogg, R. Manchester 
 Clunie, John L. L. D. Pendleton 
 Clymer, George London 
 Cocker, Jonathan Salford 
 Cogger, Thomas London 
 Colden, D. C. New York 
 Collinge, Charles London 
 Colman, J. M. Norwich 
 Colquhoun, James Sheffield 
 Compton, Joseph Manchester 
 Cook, James Glasgow 
 Cooke, Thomas Dewsbury 
 Cooper, Thomas Willis London 
 Copley, Barrow & Co, Manchester 
 Cort, & Co. Leicester 
 Cottam, George London 
 Coupland, R. & F. Leeds' 
 Cousen, James & Sons Bradford 
 Cowan, John Bolton 
 
 Cox, James Manchester 
 
 Cox. Robert Do. 
 
 Craig, William Do. 
 
 Crawshaw, Jonathan Wahefield 
 
 C lighten, J. & T. Manchester 
 
 Crossley, John & Sons, Do 
 
 Cryer, Jonathan Bolton 
 
 Cussons, Thomas Oldham 
 
 Cutfiekl, H. M. Dock Yard,, Chatham 
 
 Dacca Twist Company, Manchester 
 Daglish, John Orrell, near Wigan 
 Daglish, Robert Do. 
 Dalton, John F. R. S. President of the Man- 
 chester Philosophical Society. 
 
 Darwell, Wigan 
 
 Darwin, Soho h'olling Mills, Sheffield 
 
 Day, George Wandsworth 
 
 Dean, John Bolton 
 
 Denison, Samuel Leeds 
 
 De Volvic C'omte Chabrol, Paris 
 
 Dewer, Robert London 
 
 Dewhirst, William Halifax 
 
 Dickinson, New York, 3 Copies 
 
 Dick son, Jonathan London 
 Dimbleby, William Liverpool 
 Dobson, J. & B. Bolton 
 Dockray, David Manchester 
 Dollond, G. London 
 Donkin, Bryan London 
 Douglas, John Manchester 
 Drew, James Do 
 Dugdale, A. Do. 
 Dunlop, James & Sons, Glasgow 
 Dunn, William Do. 
 
 Dutfoy, Pans 
 
 *Dyer, I. C. Manchester, 2 Copies 
 Dyson, Joseph Halifax 
 Dyson, William Leeds 
 
 Eccles, Bannister & Co. Blackburn 
 Eckersley, J. & W. Wigan 
 Edge, Thomas London 
 Edington, James Glasgow 
 Edwards, John Manchester 
 Elliot, Thomas Do. 
 Els worth, William Preston 
 Enibden, S. London 
 
 Escher, Switzerland 
 
 Evans, John London 
 *Ewart, Peter Manchester 
 Ewing, John Glasgow 
 
 Fairbairn, Manchester. 
 
 Fairweather, John Do. 
 Farey, Joseph, jun. London. 
 
SUBSCRIBERS' NAMES 
 
 Farrer, John Halifax 
 Fauld & Woodiwiss, Barnsley 
 Faulkner, John Manchester 
 Fawcett, Richard Bradford 
 Fawcett, William Liverpool 
 Fenton & Murray, Leeds. 
 Fielden, Brothers, Todmorden 
 Fielding, H. & Brothers, Manchester 
 Fishwick and Sons Burnley 
 Flackton, Joseph Do. 
 Fletcher, Benjamin Wigan. 
 Fort, Richard London. 
 Fowden, William Manchester. 
 Fraser, James London. 
 Frost, John Manchester. 
 Furniss, P. Halifax. 
 
 Gallemore, Jesse Manchester. 
 Gallemore, William Sheffield 
 Galloway, A. London 
 Galloway, William Manchester 
 Gamett, John Liverpool 
 Garnett, John Qldham 
 Garnett, W. & S. Bradford 
 Garside, John Stockport 
 German, William Wigan 
 
 Gill, London 
 
 Gillett, John Pendleton 
 Girdwood. C. & Co. Glasgow 
 Goldie, James London 
 Goodier, John Manchester 
 Gore, Henry Do. 
 Gott, B. Leeds 
 Gough, N. Manchester 
 Goulding, & Son London 
 *Grant, William Manchester 
 * Grant, John Do. 
 
 *Grant, Daniel Do. . 
 *Grant, Charles Do. 
 Gray, Benjamin Do. 
 Green, John Do. 
 Greenway, Charles Do. 
 Greenup, W & G Halifax 
 Greenwood, Luke Huddersfield 
 Greg, John Manchester 
 Grimshaw, John Jun. Belfast 
 Grimshaw, Brothers Belfast 
 
 Hadwen, John & Co. Halifax 
 
 Hall, John Dartford 
 
 Hancome, Edward London . 
 
 Handiside, N. Glasgow 
 
 Hansard, T C London 
 
 Hardie, D Liverpool 
 
 Hardy & Andrew Stockport 
 
 Harding, Maver and Leopard, London 
 
 Harrison, Abel Stayley Bridge 
 
 
 Harrison, John Manchester 
 
 Harrison, John and Co. Charley 
 
 Haslam, S. H. Manchester 
 
 Heath, George, London 
 
 Heath, Robert Manchester 
 
 Kenwood, W. H.M. Dock Yard, Portsmouth 
 
 Heron, I, H. Manchester, 2 Copies 
 
 *Hewes, Thomas Do. 
 
 Heywood, John Stockport 
 
 Hibbert, J. Godley 
 
 Hick, Benjamin Bolton 
 
 Hickling, Thomas Birmingham 
 
 Higgins, Wm. Salford 
 
 Hill, Edwin Birmingham 
 
 Hilton, Samuel and Co. Chorley 
 
 Hind, Roger Preston 
 
 Hindley, Charles Dukenfield 
 
 Hirst, John jun. Halifax 
 
 Hirst, Marsden 
 
 Hodgson, Henry Burnley 
 
 Hodgson, William Birmingham 
 
 Holdbrook, B. Warwick 
 
 Holgate, Massey and Co. Burnley 
 
 Holmes, James Kidderminster 
 
 Holmes, John Paisley 
 
 Holt, Birch and Co. Manchester 
 
 Holt, David Manchester 
 
 Holt, Luke Halifax 
 
 Holtzapffell, Deyerlein and Co. London 
 
 Hoomans, Pardoe and Co. Kidderminster 
 
 Hope, William Liverpool 
 
 Hopwood and Pollard, Burnley 
 
 Hopwood, William Stockport 
 
 Hordern, Rev. P. M. A. Cheetham Library 
 
 Horton, Thomas Tipton 
 
 Horrocks, G. Manchester 
 
 Horrocks, Miller and Co. Preston 
 
 Hqrrox and Son, Manchester 
 
 Horsfield, Thomas Hyde 
 
 Hough, William Manchester 
 
 Houlden, John Leicester 
 
 Houldsworth, Henry Glasgow 
 
 Houldsworth, Thos. Esq. M. P. Manchester 
 
 Houtson, James Do. 
 
 Howard, Apelles Stockport 
 
 Howard, Daniel Stayley Bridge 
 
 Howard, John Leeds 
 
 Howard, John Stockport 
 
 Howard, John Warrington 
 
 Howard, J. and N. Ashton 
 
 Howard, Thomas Hyde 
 
 Howard, William London 
 
 *Hoyle, Thomas Manchester 
 
 Hughes, William Salford 
 
 Hull, John Manchester 
 
 Hulse, Joseph Alfreton 
 
 Humphries, Robert Glasgow 
 
 ppp 
 
SUBSCRIBERS' NAMES 
 
 Hutchinson, John Manchester 
 Hutton, James Leeds 
 Huzzie, William Glasgow 
 Hyde, John Manchester 
 
 Jackson, M. London 
 Jackson, William Oldham 
 James, James Birmingham 
 Jenkinson and Bow., Salford 
 Jones, George Birmingham 
 Jones, James Do. 
 Jones, John Bolton 
 Jones, Joseph, jun. Oldham 
 Jones, William Manchester 
 Johnson, G. London 
 Johnson, Owen Birmingham 
 Jordon, Francis Liverpool 
 Joule, Benjamin Salford 
 
 Kay, Alexander Manchester 
 Kelly, W. and S. Leicester 
 Kennedy, James Manchester 
 * Kennedy, John JDo. 
 
 Kenworthy, John Ashton 
 Kilburn, James Leeds 
 
 King, ; Manchester 
 
 Kirk, Benjamin Do. 
 Kirkland, Thomas Mansfield 
 Knight, Samuel Manchester 
 
 Lane, 
 
 Manchester 
 
 Lane, Joseph Stockport 
 
 Lane, William and Sons Manchester 
 
 Landless, William Burnley 
 
 Latham, John Manchester 
 
 Lawson and Walker, Leeds 
 
 Lee, G. A. Salford 
 
 Lees, Henry Ashton 
 
 Lees, Jerry Manchester 
 
 Lees, Jonathan Do. 
 
 Lees, Samuel Oldham 
 
 Leese, Joseph Manchester 
 
 Lewis, F. Do. 
 
 Li gh toller, T, Charley 
 
 Lillie, Manchester 
 
 Lloyd, Lionel Da. 
 
 Lobley, Matthew Leeds 
 
 Lockett, Garnett and Co. Manchester 
 
 Lockwood, Joseph Huddersfield 
 
 Lockwood, Leeds 
 
 *Lomas, William Strangeways, 2 Copies 
 
 Lomas, George Bolton 
 
 Longman and Co. London 
 
 Longsden, P. and J. Manchester 
 
 Longworth, N. Bolton 
 
 Lonsdale, Daniel Manchester 
 
 Lowe, John Shepley Hall 
 
 Lowe, George London 
 Lucas, Jonathan Charleston 
 Lumb, Joseph Leeds 
 Lupton, Jonathan Leeds 
 
 M f Andrew, William Glasgoiv 
 M'Arthur, Duncan Do. 
 M'Connell, James Manchester 
 Machan, Luke Sheffield 
 M'Murdo, G. Soho, Manchester 
 M' Naught, John Glasgow 
 M'Naught, Patrick Do. 
 Macray, James Manchester 
 Malum, George London 
 Malam, J. Do. 
 
 Manchester Exchange Library 
 
 New Library 
 
 Manwaring, George London 
 Marriott, Christopher Manchester 
 Marsden, William Salford 
 Marsland, Henry Manchester 
 Marsland, James Burnley 
 Marshall, James Stockport 
 Marshall, Isaac Birmingham 
 Marshall, W. and T. Bradford 
 Maskray, James Manchester 
 Mason, John Bradford 
 Mattinson, J. Huddersfield 
 Matterface, A. London 
 Maudsley, Henry London 
 Mawson and Bown, Bradford 
 Mayer, Joseph Stockport 
 Melling, John Bolton 
 Mellor, James Manchester 
 Mellor, Thomas Ashton 
 Middleton, John London 
 Miller, John London 
 Millington, John F. R. S Do. 
 Milne, William Edinbro' 
 Milne, E. Manchester 
 Milne, W. Do. 
 Milne and Turner, Halifax 
 Monks, Samuel Bolton 
 Monteith, H. and Co, Glasgow 
 Montgomery j Robert Johnston 
 Moore, Daniel Birmingham 
 Moore, Joseph Leeds 
 Moore, S. M. Manchester 
 Mosedale William Do. 
 Moss, Thomas Wigan 
 Mottershead, Samuel Manchester 
 Munday, Thomas Preston 
 Muntz, G. F. Birmingham 
 Murdock, Wm. Soho, Do. 
 Murdock, William Manchester 
 Murgatroyd, John Halifax 
 Murray, George Manchester 
 
SUBSCRIBERS' NAMES. 
 
 Napier, David Glasgow 
 
 Naylor, Benjamin Manchester 
 
 Neild, William Do. 
 
 Neilson, John Glasgow' 
 
 Nelson, William Manchester 
 
 Newton, Samuel London 
 
 Newton, Scott, Chambers and Co. Thorncliffe 
 
 Iron Works 
 
 Nichols, Benjamin Manchester 
 Norris, H. Bolton 
 
 Occleshaw, William Manchester 
 Ogden, John Do. 
 
 Olliver, G. Do. 
 
 Ormrod, Richard Do. 
 
 Orrell, John Stayley Bridge 
 Oswald, James aud Co. Glasgow 
 Ousey, Judson Stayley Bridge 
 Outram, G.for Glasgow Foundry Co. 
 
 Paget, J. and W. Loughborough 
 Paley, John Preston 
 Palmer, R. London 
 Park and Sons, W'gan 
 Parker, F. Sheffield 
 Parker, Samuel London 
 Parkes, Josiah Manchester 
 Parkin, Jonathan Leeds 
 Parkinson, Adam Manchester 
 Park Mills Co. Stockport 
 Parry, Thomas Manchester 
 Patten, Thomas and Co. Cheadle 
 Pearson, Barwise Chester 
 Peel and Co. Manchester 
 Peel, G. Soho, Do. 
 Perm, John Deptford 
 Pennington, Richard Manchester 
 Percival, William Stockport 
 Perkins, Jacob London 
 Perrier, George Do. 
 Petrie, A and Co. RocMale 
 Phillips, Nathaniel Manchester 
 Phipson, J. W. Birmingham 
 Pollard, Jonathan Manchester 
 Poole, M. London 
 Pooley, John Manchester 
 Pope, Henry Do. 
 Pope, Henry, jun. Do. 
 Potter, John Do. 
 
 Powell, John Do. 
 Proctor, James and Sons Leeds 
 Proctor, John Do. 
 
 Pullan and Sons Do. 
 
 Raby, Richard Leicester. 
 Radcliffe, James Stockport. 
 Radford, Joseph Manchester. 
 Railton, Robert Blackburn. 
 
 Ramsbotham, Henry Todmorden. 
 Ramsden, John Halifax. 
 Ransome, James Manchester. 
 Rathbone, R. Liverpool. 
 Rawson & Saltmarshes, Halifax. 
 Ready, Thomas Peckham Academy. 
 Reid, John & Co. Manchester. 
 Rennie, George. London 
 
 Richardson, Wigan. 
 
 Rickards, Charles Manchester. 
 Roberts, Brother & Co. Burnley. 
 Roberts, Richard Manchester. 
 Rose, John Leeds. 
 Rothwell, P. jun. Bolton. 
 Rothwell, Richard Manchester. 
 Roughton and Woodhouse, Coventry 
 Rowlands, R. Glasgow 
 Royston, Charles Halifax 
 Rushforth, Joseph Elland 
 Rushton, J. Liverpool 
 Rushton, William jun. Do. 
 Ruth Patricroft 
 
 Sadler, James Mansfield 
 
 Samuels, John Manchester 
 
 Sandford, Benjamin Do. 
 
 Sandford, William Leeds 
 
 Sandiford, James Manchester 
 
 Satterthwaite, E. Belfast 
 
 Sells, John Manchester 
 
 Sells, Henry Do. 
 
 Schlumberger, Grosjean & Co. Muhlhausen 
 
 Schofield, Joseph Manchester. 
 
 Scholes, Varley & Co. Do. 
 
 Sharp, William Salford. 
 
 Sharp, James Paisley. 
 
 Shaw, Joseph Sheffield. 
 
 Shaw, Joseph and Sons, Leeds. 
 
 Sheffield Coal Co. Park. 
 
 Sherbrook, T. Leeds. 
 
 Sherratt, John Salford. 
 
 Sherriff, London. 
 
 Shuttleworth, J. Manchester 
 Sidebotham, John Hyde 
 Sidebotham. Samuel Stockport 
 Simpson, Richard Manchester 
 Sinclair, John Atherstone 
 
 Sior, Somers Town 
 
 Slater, Thomas Salford 
 
 Sleddon, Francis Preston 
 
 Smith, Alexander Birmingham Gasworks 
 
 Smith, Alexander Manchester 
 
 Smith, Benjamin Do. 
 
 Smith, E. & C. Chesterfield 
 
 Smith, Henry, Birmingham 
 
 Smith, Joseph Manchester 
 
 Smith, O. H. Chelsea 
 
SUBSCRIBERS NAMES 
 
 Smith, Thomas Burnley 
 
 Smith, Thomas J.eeds 
 
 Snodgrass, Niel Glasgow 
 
 Solly, R. H. London 
 
 Spencer, John Burnley 
 
 Spooner, Ralph Bolton 
 
 Stables, W. W, and H. H. Huddersfield 
 
 Stamtin, H. Carron Wharf London 
 
 Stansfield, Briggs and Co. Halifax 
 
 Stansfield, John Todmorden 
 
 Stark ey, Buckley and Co. Huddersfield 
 
 Steel, Thomas and Son, Stockport 
 
 Stirk and Horsfield Leeds 
 
 Stock, Aaron Wigun 
 
 Stocks, Benjamin Manchester 
 
 Stockton, Joseph Do. 
 
 Stone, James London 
 
 Strutt, A. R. Derby 
 
 Strutt, William Do. 
 
 Stuart, John Manchester 
 
 Sturges, John and Co. Bowling Iron Works 
 
 Sutclifte, John and Nephews Halifax 
 
 Swindells, John Manchester 
 
 Swire, Samuel Ashton 
 
 Sykes, Richard Edgely 
 
 Tattersall and Crooke Burnley 
 Taylor, Josiah Holborn, London 
 Taylor, Benjamin Glasgow 
 Taylor, J. and J. Manchester 
 Taylor, Phillip London 
 Taylor and Shatwell Manchester 
 Taylor, William Preston 
 Taylor, W. G. Bolton 
 Taylor and Wordsworth Leeds 
 Taylor, Edward Warwick 
 Telford, Thomas F. R. S. London 
 Tennant, C. and Co. Glasgow 
 Thackray, Jonathan Sheffield 
 Thomson, R. jun. Glasgow 
 Thompson, M. Bradford 
 Thompson, Samuel Bolton 
 Thompson, Thomas Do. 
 Thompson, Thomas Newcastle 
 Throp, William Blackburn 
 Tilley, J. London 
 Tipping, G. Manchester 
 Tomlinson and Co. Oldham 
 Tongue, William Birmingham 
 Townend, G. and W. Manchester 
 Townend, William Do 
 
 Travis, James Halifax 
 Turner, Thomas Nottingham 
 Twigg, Joseph jun. Paisley 
 
 Unwin, Samuel and Co . Mansjield 
 
 Vanhouse, James Peckharn 
 Varley, John Manchester 
 Vaudrey, John Stay ley -bridge 
 Vickers, William Manchester 
 
 Wade, Joseph Bradford 
 
 Waddington, David Manchester 
 
 Wainwright, Benjamin Stayley -bridge 
 
 Wakefield, John Manchester 
 
 Walker, Benjamin Leeds 
 
 Walker, Henry, Salford 
 
 Wareing, J. and W. Stay ley -bridge 
 
 Watson, Peter Manchester 
 
 Watson, William Glasgow 
 
 Weight, Joseph Manchester 
 
 Weight, Hezekiah Do. 
 
 Weir, Edward London 
 
 Weir, Charles Alexander Kent Water works 
 
 Welch, Thomas Manchester 
 
 Wentworth, H. Wandsworth 
 
 Wentworth, James Deptford 
 
 Westley, W. K. Leeds 
 
 Wharton, Joseph Manchester 
 
 Wharton, William Do. 
 
 Whitacre, John Huddersfield 
 
 White, John Glasgow 
 
 Whitehead, John Halifax 
 
 Whitfield, William Birmingham 
 
 Whyatt, George Manchester 
 
 Wigan, R. Do. 
 
 Wilder, O. London 
 
 Willans, Thomas Leeds 
 
 Williams, John London 
 
 Willoughby, J. Birmingham 
 
 Wilkinson, James Leeds 
 
 Wilkinson, James Stayleybridge 
 
 Wilkinson, George Middleton 
 
 Wilson, George London 
 
 Wilson, William jun. Nottingham 
 
 Wilson and Co. Leicester 
 
 Wolfenden, Richard Manchester 
 
 Wolfenden, Stones and Kirkham Manchester 
 
 Wood, Alexander Do, 
 
 Wood, John Huddersfield 
 
 Wood, John Manchester 
 
 Wood, John Stockport 
 
 Wood, George Manchester 
 
 Wood and Harrop Ashton 
 
 Wood, Robert Leeds 
 
 Woodcock and Harrison Leeds 
 
 Worswick, John Manchester 
 
 Wright, John Oldham 
 
 Wright, Joseph Ashton 
 
 Yates, Thomas Manchester 
 Young, Joseph Do. 
 Young and Smith, Sheffield 
 
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UNIVERSITY OF CALIFORNIA LIBRARY 
 BERKELEY 
 
 Return to desk from which borrowed. 
 This book is DUE on the last date stamped below. 
 
 953 
 
 tEC'D LD 
 
 IDEC151961 
 APR 13 1987 
 
 AUTO.OISC.MAR26 
 
 LD 21-100m-7,'52(A2528sl6)476 
 
GENERAL LIBRARY- U.C. BERKELEY