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were left to their fate; and consequently every at- ing about thirty-six years of age; and the important tempt to throw off their Turkish fetters served only changes which he has already

effected, namely, the to make their oppressors load them with heavier annihilation of the turbulent and seditious janissa. chains. Gladly, indeed, would the Czars have con ries, and the subjection of the ulema and pachas to verted this beautiful country into a Russian pro- the obedience of the laws, testify his unshrinking vince, and would willingly have bartered for it the

courage and resolution. Upon the occasion of the richest jewel in their crown; but their ambition and unfortunate battle of Navarin, when all Europe cupidity have hitherto been restrained only by the seemed banded against him, his calmness and prudifficulty of the enterprise.

dence, though severely tried, did not forsake him; The same selfish policy has dictated the present and he evinced a spirit of justice and forbearance interference of the Russian autocrat in the libera- very unusual in any prince of his line, in his treattion of Greece. It cannot be presumed that he, ment of foreign merchants, who, while they looked who lords it over a nation of slaves, can have one for the usual measures of confiscation and the bowfeeling in common, in such a cause, with the en string, were generously protected in their lives and lightened sovereigns of Great Britain and France, property. Though conquered, Mahmoud still perwho rule over free-born men. His uniform object severes with unabated zeal in completing his plans has hitherto been territorial aggrandisement and of reform in the military and naval services, and in political influence; and his admiral, count Heyden, preparing his empire for future emergencies. By when he prevailed upon his colleagues in command the introduction into his army of European discito destroy the combined fleet in Navarin, had in pline and tactics, and by his own adoption, on many view ulterior measures, which these officers could occasions, of the European costume and manners, not have contemplated. Great Britain and France, so obnoxious to the pride and superstitions of Musby thus admitting the interference of Russia in ob- sulmans, he has shown himself superior to the keentaining a favourite measure, have enabled her to est prejudices of his nation, and is thus gradually reward herself with a princely remuneration; for freeing himself from the authority of those ancient we have no hesitation in maintaining, that it was to forms and opinions by which his predecessors were the destruction of the Turkish fleet, and to the dis- held in thraldom. He has already done much for solution of the Turkish janissaries, that Russia was the advancement of his people in civilization and mainly indebted for her ultimate success in her con- happiness; and the condition of slaves throughout flict with the Ottoman porte. Had this fleet been his dominions has been so considerably ameliorated preserved for the defence of Varna and the coasts during his reign, that they enjoy more freedom and of the Euxine, the Russian army would never have comfort than the serfs either of Russia or Hungary. crossed the Balkan; or if it had, and the disbanded We are afraid, however, that, owing to the vicious janissaries of Adrianople had been true to their structure of society in this country, the religious country's cause, instead of harbouring resentment prejudices and fanaticism of the people, and their against their prince, count Diebitsch, deprived of general inaptitude for improvement, the task of resupplies and reinforcements by sea, would in all novating Turkey will prove too Herculean even for likelihood have experienced the fate of Peter the Mahmoud. In the following extract from a recent Great on the Pruth, at Falczi. Russia, however, work on Turkey, the sultan is described as unre. is now triumphant, and she may insist upon her mitted in directing and managing the affairs of his adversary paying the uttermost farthing of his government: “ Il surveille son Divan avec un soin bond; but torrents of blood must flow before her extrême, et ne lui laisse que le simulacre du pouplans of aggrandisement be completed; and she voir; il dirige, il regle tout par lui-même; en un may perhaps never again find such a union of cir- mot il est lui seul le gouvernement. Mieux et plucumstances so favourable to her views. She may tôt informé que les ministres au moyen d'une agence have also learned, from her own practice and ex secrète três-active, ses mesures sont prises avant perience, that a treaty made in the hour of peril is que les rapports de son Grand Vizier lui soient considered no longer obligatory when the danger is parvenus. Actif, laborieux, d'un secret impénétrapast; and the present ruler of Turkey will not let ble, observateur zélé de sa religion, fidêle à sa paslip any opportunity of retaliating upon the foe of role, sobre et respectant les moeurs, Sultan Mahhis house the wrongs and injuries which have been moud peut être regardé á juste titre comme un accumulating for a century.

phénomène pour la Turquie." See Knolle's TurkIf Turkey is to be renovated, and to be brought ish History; Thornton's Present State of Turkey; within the pale of civilized Europe, no prince of Eton's Survey of the Turkish Empire; Upham's the line of Othman has ever appeared with qualifi- History of the Ottoman Empire; Malte-Brun's Gecations and attainments better suited to its circum- ography, vols. ii. and vi.; Foreign Review, Nos. 1, stances and its wants than its reigning sultan. 3, 5, and 6; and Annual Register, vols. xiii. xix. Mahmoud II. is at present in the prime of life, be

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TURNING.

§ 1. Under this head we comprehend all opera. est to the spindle of the lathe; it is bored out cytions performed in the turning lathe, in which the lindrically, and forms the socket in which the stem object operated on is so disposed as to revolve or stalk of the cutter or tool-holder is fixed by a round its axis, while a cutting instrument is applied pinching screw G, in the same way as in the sockto it; or in which it is successively fixed in dif- ets of common rests. This socket should be bored ferent positions of its rotation, and then operated truly perpendicular to the planes of the slides. on by instruments of various kinds, moving in cir. § 6. The sliding plates mentioned above are each cles, in portions of circles, in other curves derived moved in its own path by a leading screw turned from circular motion, or in straight lines.

by a winch handle, * and it will be obvious that by § 2. The art of turning in its simple form is of turning the winch of the leading screw, that plate, great antiquity, and is susceptible of niore accuracy with every thing on it, (including the socket É and than almost any other mechanical operation. We cutter holder F,) will be made to advance or retire shall not attempt to give any description of the in a direction perpendicular to the axis of the manipulations required in its application in the spindle, or of the article to be turned, and that, by more common cases, as these cannot be well learn- turning the winch of the upper leading screw, the ed but by practice, under the guidance of an expe- saddle D, with the socket E, and cutter holder F, rienced artist.

must move in a path parallel to the axis of the $ 3. The great demand for accurate workman- lathe, or of the work, and therefore that the article ship which has been occasioned by the improve turned must necessarily assume the form of a cylinment of the steam engine, and the consequent ex der. By a combined simultaneous motion of both tension of machinery and manufactures, has led to winches, the point of the tool may be made to pass important improvements in the art of turning. Of through any assignable line in a plane parallel to some of these we shall endeavour to give such a the slides. description as may convey to artists who may not $ 7. As, however, it is often necessary t8 turn have had an opportunity of seeing their applica- conical objects, an adjustment is provided in the tion, some idea of the effects which may be obtain- construction of the rest which facilitates the pered by means of them.

formance of this operation with extreme accuracy. 94. The most important of these improvements It was mentioned above, that the upper and lower on the old method of operating by hand-tools, and sliding plates B and C are attached to one another that on which most of the other improvements are in a particular way, which is this: a solid cylindri. founded, is what is commonly called the slide-rest. cal pin H passes vertically through both plates near This, in what is called ornamental turning, is a their middle; this pin is screwed into the upper small apparatus which is occasionally fixed in the one, but passes through a well-fitted cylindric hole socket of the ordinary rest, (having a cylindrical in the lower one B, and so forms a joint round stalk for this purpose,) consisting of a cutter which the upper slide may be turned when the holder, or carriage which slides along a narrow screw is slackened; the edge of the upper plate platform, and is regulated in its motion by a lead. which is nearest the workman, is a portion of a ing screw, which has a small winch, or a milled circle of which the above mentioned joint H is the and divided head at its right-hand extremity. centre, and is divided into degrees, and marked in

$5. In the best construction of lathe for working such a way that, when the two slides are truly at in metals, the arrangement is different. The right angles to one another, the division marked foundation of the slide-rest is a sole A, (Plate zero is at the index, and the other divisions marked DXXVII. Figs. 1, 2, 3, and 4,) which can be fixed 10°, 20°, &c. on the right and left of zero. When at any required part of the bar or bed between the it is required to turn a cone of any particular angle iwo heads of the lathe. On this sole there is a of inclination, the upper plate is turned to the right solid plate B, which slides in a path adjusted truly or left until the corresponding number of degrees at right angles to the line of the axis of the spindle comes to the index; it is then fixed in that position or mandril: on this sliding plate, another solid by its pinching screws. If the winch of the upper plate C is attached (in a way which will be men- leading screw be now turned round, the point of tioned afterwards), and on this plate C is formed a the tool will describe a straight line having the reslide at right angles to the first one, (and conse- quired inclination to the axis of the work, and so quently parallel to the axis of the spindle) On will turn either an external or internal cone accordthis slide a piece D (sometimes called the saddle) ing as the cutter and the work may be disposed; moves; this saddle has an excrescence E rising ex. gr. the key and the socket of a brass cock may from its upper surface on that side which is near. be turned in this way with such perfect accuracy

• In some sorts of work, such as the cutting of teeth of wheels, and drilling deep holes, it is more convenient to take out the leading screws, and to work the slides by levers.

that the one, on being dropped into the other, will § 12. 3d case. Again, with the same preparabe perfectly water-tight without much further pre- tion, a third effect may be produced. Suppose the paration or grinding.

first hole pierced as before, and the drill withdrawn $ 8. The great advantages which this construc- from it, then if the work be turned round 1-12th of tion has over the old one is, that when once well a circle, and also the upper winch turned as many adjusted, it may be successively applied at different turns as in the second case, the second hole, when situations without any fresh examination or adjust- made, will be found to stand diagonally to the first; ment; and that, as the socket partakes of the regu- and if the operation be repeated 12 times in the lated movements of the slides, every instruinent or same way, the 12 holes will have taken a helical piece of work which is put into that socket, be- direction round the cylinder, and if short spokes comes subject to these movements.

were fitted into them, they would stand like what $ 9. If, therefore, instead of putting a simple are called the pins of a wiper beam. cutter holder (like F Fig. 1 or 4) in the socket, we § 13. 4th case. If the drill, instead of being put any instrument capable of producing a particu- allowed to penetrate so far as to make a hole, were lar effect by a motion of its own, this instrument stopped in its advance when no more than its cutting may (by means of the movements and adjustments part had entered the substance of the work; and if, of the slides) be made to produce its effect on any while in this situation, the winch of the upper particular parts of the work, either in continuous leading screw were to be turned (the drill still conlines, or in parts in a regulated succession, as the tinuing to revolve), its point would necessarily cut work (which will remain fixed while the instrument away the substance of the work in the direction in is operating) may (by means of a divided plate on which it was led by the screw, and would in this the face of the spindle pulley) be presented suc- way cut a longitudinal furrow instead of a circular cessively in any required number of positions. hole. The shape of the bottom of this furrow would

10. One of the most useful of the instruments depend on the form of the point of the drill. which may be so applied, is a drilling apparatus. Ś 14. In these four cases we have supposed the Let the reader suppose that a frame containing a drill to be capable of drilling holes only at right strong drill mandril A is so constructed that when angles to the axis of the work, but this would obit is fixed into the socket of the slide rest, the axis viously be too limited a range of operation. It is of the mandril is parallel to the path of the lower necessary, therefore, to have some means of adslide,* and that by some proper arrangement of vancing the drill arbor independent of the action of bands and pulleys this drill stock can be made to the lower leading screw, and this is done by having turn with the requisite velocity; next let him sup- a slide B in the construction of the instrument itself, pose a drill in the stock, and a cylindric piece of as seen in Fig. 5. This slide is parallel to the axis work in the lathe, then if the pointer be applied to of the drill arbor, and as the instrument, when put any of the holes in one of the circles, in the face into the socket of the slide rest, may be set with its of the pulley (of the spindle) having twelve divi- own slide obliquely to the work (having divisions sions, one or other of the following effects may be and an index as at C for this purpose), the advance produced.

of the drill into the work may be made in any reIst case. If, while the drill mandril is revolving, quired direction, while its other movement will dethe winch of the lower leading screw be turned pend as before on the leading screws of the slide rest. forward, the drill will advance and will continue to $ 15. The term drill has been used here to desigpierce a hole towards the axis of the cylinder. If nate the cutting part of this instrument, but this ihe drill, after going to a certain depth, be with must not lead the reader to suppose that the form drawn clear of the hole, and the work be turned of the cutting tool is limited to that usually seen in round until the pointer falls into the next hole in boring instruments. Revolving cutter would be a the divided circle of the pulley, the drill may be better designation, were it not appropriated to anagain advanced to perforate a second hole, and so other instrument, of which we shall have to speak on until the number 12 is completed. In this way presently. In point of fact, an endless variety of sockets for the spokes of a wheel may be accurate cutters may be employed in a well constructed aply bored, or any analogous operation may be per- paratus of this kind, and effects may be produced formed.

by a judicious application of them, which, until $11. 2d case. But with the same preparation a lately, were never attempted by the turner. The different effect might have been produced. After nose D of the arbor may be screwed like that of the first hole had been made, if instead of turning the spindle of the lathe, and by means of metal the piece of work in the lathe 1-12th part of a chucks (similar to that shown at N, Fig. 2, Plate circle, we had turned the winch of the upper lead. DXXVI.) fixed on it, eccentric cutters of various ing screw a certain number of turns, and then had kinds may be employed according to the wants of drilled a second hole, and if we repeated this alter the artist; this will be understood by inspecting the nate operation 12 times, we should then have had figure. We cannot, according to our prescribed 12 holes as before, but with this difference, that limits, go further into the detail of the adaptations they would now be disposed in a straight line pa- of this useful instrument than just to show, by way rallel to the axis of the cylinder.

of example, how it may be employed to produce flat

* In Fig. 5 the drill mandril has been represented in a position parallel to the path of the upper slide, and to the axis of the lathe, i. e. in a position for drilling face work.

surfaces in different parts of the same piece of it to cut off the slice without the neck of the arbor work.

interfering, the friction would consequently be great. § 16. Let us suppose we have turned a sphere of $ 18. The drill apparatus must then be removed ivory from which we want to cut away such por. from the slide rest, and the pointer from the divided lions as would leave a cube. It is obvious that in circle, so as to leave the lathe and work free to rethe old way of turning by, by making the work re volve. The ordinary cutter or tool holder is then volve and the tool remain comparatively at rest, to be put in the socket of the rest, and furnished that only one of the six faces could be cut in this with a well set parting tool. This tool is to be way without removing the work from the chuck; brought by the leading screws to the proper posiand that the greatest possible accuracy in refixing tion for making a cut perpendicular to the axis of the it after removal, could hardly ensure a successful work at the right hand extremity of the intended result.

cube; the work being then put in motion, and the tool § 17. By means of the instrument just described, advanced by the lower winch, a fifth plane will be cut the whole six faces may be prepared without un on the end of the work, and a slice of the form of fixing the work from the original position in which a plano-convex lens will be cut off; this face being it was made into a sphere. We shall suppose, completed, either at one or at repeated cuts, the then, that the sphere is attached to the chuck by a place of the tool holder must be shifted by the upper neck strong enough to bear the operation of cutting leading screw, to permit the cut to be made which the planes, and that we have ascertained the exact is to form the sixth face, and of course to detach length of the side of the cube contained in the given the cube from its connexion with the mandril. sphere. The first thing to be done is to select some $ 19. It will be evident to the reader that if the circle on the pulley of the lathe spindle divisible by operation be conducted with proper caution, and 4, into one of which divisions we fix the pointer. the divided circle on the pulley be accurate, the reWe then choose an eccentric cutter for the drill sult must necessarily be an accurate cube. The arbor, similar to that seen in Fig. 2, Plate DXXVI. intelligent artist will also see, that by a slight the sweep of which must include a circle whose variation of the process other geometrical solids diameter is something greater than the side of the may in like manner be produced, and many analointended cube: the form of its cutting edge is not gous operations performed. very material in the first stage of the operation. $ 20. We mentioned above that the name of reThe slides of the rest, and of the drill apparatus volving cutter was appropriated to another instrubeing set accurately at their respective zeros, and ment which may (like the drill apparatus) be apthe arbor itself being somewhat to the right hand plied in the socket of the slide rest. When a lathe of the piece of work, it must be set in motion by is provided with well divided circles on the pulley the band, and carried to the left by the upper lead- of its mandril, and a properly constructed revolving screw until the cutter just begins to impinge on ing cutter apparatus, it becomes an engine of extenthe surface of the sphere. The depth of cut is of sive powers for cutting the teeth of wheels. course to be regulated by the lower leading screw, This instrument consists of a frame carrying a and should not exceed 1-40th or 1-50th of an inch spindle A, generally vertical, but which may be set each time; in this way, by making the cutter re- (within certain limits) at any degree of obliquity in peatedly pass from right to left over the face of the à vertical plane, and round a centre which is in the sphere, advancing the lower slide each time by the plane of the axis of the lathe. In all the positions depth of a fresh cut, one face of the ball may be cut which it can assume, except the horizontal, its lower down nearly to the required depth. The index point extremity or point B is below, and its upper collar is then to be made to fall into another quadrantal or neck C is above the plane of the centres of the division, and the same operation repeated to the lathe. At a point between the pivot and collar, same depth, and so on with the two remaining ones. and exactly level with the lathe centre (and conseWhen the first face has been cut away, the plane quently with the centre of its own adjustment) cirface will be bounded by a circular line; but when a cular cutters (as at D) like those of a clockmaker's second has been cut, the intersection of these two engine, may be fixed on the spindle. Let us supplanes will form a straight line which should, in pose the spindle in the vertical position, fitted with this stage of the operation, be a little shorter than a cutter, and a piece of work in the lathe in which the side of the intended cube. A new very sharp it is required to cut 120 leeth. It will be seen that cutter should now be fixed in the chuck of the drill all we have to do is to bring the revolving cutter arbor, having its cutting edge straight, and truly directly opposite the edge of the work, to select a at right angles to the arbor; with this the same circle on the pulley of 120 divisions, and having operation must be repeated on all the four faces, fixed the pointer in the first division, to advance the until the lines of intersection of the four planes be cutter against the work by the lower leading screw exactly equal to their breadth, and the planes them to the proper depth. This being repeated for each selves perfectly smooth. Instead of the eccentric of the 120 divisions, the operation is completed. cutter, a cutter like a small circular saw might If, instead of a thin wheel, the work be a pinion have been fixed on the nose of the drill arbor, and of considerable length, it may be necessary, after the four lenses cut off the sphere in succession, but having made the first cut to the proper depth by the same smooth finish could hardly be given in this means of the lower leading screw, to extend the cut way, and the diameter of the saw would require to to the right or left by means of the upper one; in be more than twice the size of the cube to enable such cases, it is best to make all the cuts after the VOL. XVIII. Part I.

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194

first, by means of the upper winch alone, winding sume much time even in the hands of the most exthe cutter clear of the work each time to allow for pert workmen. In good slide-rests there are stops the shift being made in the divided circle.'

and adjusting screws for regulating the depth and $ 21. We have said that the cutter spindle may length of the cuts. We have not attempted to debe set obliquely, or even horizontally. This is scribe them, as this would lead us into too minute effected by making that part of the frame, in which a detail. Some of them may be seen in the enthe step and collar of the spindle are formed (see gravings. E, Fig, 6, Plate DXXVII.) turn on a centre which $ 27. In machine maker's work-shops, where passes through the portion of the frame which is heavy. work is turned, such as shafts, large rods of fixed in the socket of the slide rest. This centre is steam pistons, &c. the slide-rest is differently conlevel with the centres of the lathe, and consequently, structed, and is more strictly what its name indi. whatever angular position the spindle may be put cates. Instead of a part of it being fixed to the in, the circular cutter will always tend to cut bed, and the saddle with the cutter holder being directly towards them.

made to slide on it by a leading screw within itself, 22. Many operations besides the catting of the the whole body of the rest is made to slide to the teeth of wheels and pinions may be performed by right or left along the bed of the lathe, sometimes this apparatus, as the form of the cutters, the posi. by an endless screw within itself, which works into tion of the spindle, and the movement to be given a kind of oblique toothed rack, extending all along to them may be varied in many ways by the intelli. the bed, and sometimes by a leading screw of gent artist, according to the purpose he has in view. the length of the bed which works in a female $ 23. In all the cases subsequent to $ 9, we have screw socket in the sole of the rest.

This leading supposed the work or article operated on to be fixed screw is worked by wheel work from the lathe in the lathe (by means of chucks or otherwise) and mandril, and the requisite degree of speed is given the cutting instrument to be in rapid motion round to the motion of the rest by proportioning the sizes its own axis. There are cases, however, in which and numbers of the wheels, pinions, and pulleys. the situation of the work and the tool may be re $ 28. By this last arrangement, a very convenient versed, the work may (by different methods accord method is obtained of cutting long screw bolts, or ing to circumstances) be fixed in the slide-rest, and original screws of every variety of pitch, as we have the tool may be fixed in, or on, the nose of the only to put on such trains of wheels and pinions as lathe mandril.

we ascertain by calculation to be necessary to give $ 24. In this way a piece of wood or metal which the relative degrees of velocity to the mandril and is to be sawn in parallel cuts, or cuts at certain in to the cutter in its motion to the right or to the left, clinations to one another, being properly made fast and we shall then, by presenting a cutter of proper to a frame or vice held in the socket of the slide- form, succeed in cutting a screw of any length rest, we may cut it in a variety of planes by a cir- which the lathe can take in. If the cutter moves cular saw fixed on the lathe mandril, because by to the left while the work revolves the right way, it means of the divided arch on the upper slide of the will cut a right hand thread; and if it move towards rest, we may set it to the required angle, and then the right, while the work is revolving the right by the lower winch we may advance it against the way, the result would be a left hand thread of the edge of the saw.

same pitch. The thread will be angular, square, Š 25. Instead of a circular saw, we may put drills or round, and deep or shallow, according to the of large sizes into the lathe mandril, and fixing the form of the cutter which may be selected. article to be bored on the slide-rest, we may present $ 29. The female screw or nut of the same pitch it, and advance it against the drill by means of the may be cut in two ways. leading screws. This process will often be useful ist. The work to be screwed may be chucked, when the drill is large, and the resistance too great and a hole of the proper size having been bored in to be conveniently overcome by the apparatus de it, a side cutter being presented either at the mouth scribed in § 10, &c.

of the hole, or at its bottom (according as the thread It may sometimes happen that the risistance is is to be a right or left one) the lathe being then put too great to be easily overcome by the leading in motion, ihe tool will advance or retreat (as the screw of the upper slide. In this case it may be case may be) while the work turns round, and the as well to disengage the leading screw and winch, thread will be gradually cut to the proper depth. and to bring the moveable head of the lathe so close 2d. If the work be of such a nature that there are to the work, that the upper slide, together with the a succession of holes to be tapped, it may be fixed work on it, may be pressed towards the drill, by on the slide-rest, and one of the holes brought truly the screw of the right hand head stock.

into the line of the centres; then by means of a re$ 26. We have endeavoured in the foregoing pa. volving cutter (of one point) fixed in the lathe manragraphs to give some indications of what may be dril, the thread in the hole may be gradually cut done in a lathe with a well constructed slide-rest. to the required depth by increasing the eccentricity The intelligent artist will see that by some of the of the revolving cutter at each shift of motion. contrivances pointed out, or by some modification The other holes in the work must then be brought or combination of them, he may perform with com in succession (by means of the slides of the rest) parative ease, and great precision, many operations into the line of the centres, and the same process which, in the ordinary way, must be done in the repeated. vice by chipping and filing; and which would con

In this process, the motion of the lathe mandril

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