Lapas attēli




877 through. Fig. 3 is a similar plate of thread, the other made to match its uppo. thick sheet-iron, not rivelled fast, but site die as before, a right and left-handed screwed on the upper side of the stock double-threaded screw may be cut; those with four screws aaaa in the holes e eee Wedges are very easily made and fitted. of lig. 1, so as to be taken off at pleasure. The great superiority of this method to Fig. 5 is one of the dies, aud fig. 6 the the common dies now in use, the most in. other, with wedges, wlich will be de. different oliserver cannot help observing; scribed again. Fig. 4 is a screw for mus. the ease and simplicity with which they ing the die (fig. 5) on between the plates are constructed, and the extent of the as it cuts. Fig. 7 is a master-lap for work performed, will no doubt render it cutting similar dies ; and fig. 8 is a view preferable, and also insure its inmediate of fig. 6, with the wedges in the proper adoption in the mechanical world. places, as they ought to he, when you wish to cut a right-handed screw.

Yours, &c. It will be seen that in the dies there is

JAMES TRACEY. no rake or thread, consequently when set

Pembroke, May 2, 1836. in between the plates, in the stock, the ends of the die, fig. 6, being previously supplied with four wedges of equal thick.

HEINEKEN'S SCREW-CUTTER. ness, the notches or indentations in each die would be perfectly opposite and pa

A А rallel to each other, and would not cut a screw, but would be in the proper position for cutting a master-lap, fig. 7, or for the master-tap when made to cut the dies. From this it will be seen, that one mastertap could be turned in the lathe with three or more indentations of different

c sizes, abc, &c. fig. 7, which would cut as Inany different sized pairs of dies. Take off the plate, fig. 3, by unscrewing the screws aa aa, and also take the moveable die, fig. 6, out; then, instead of wedges of equal thickness, introduce those of lig. 6, and the die will have the position of fig. 8; screw the plate, fig. 3, on again, and the instrument is in its proper

place for cutting a righi-handed screw. unscrew as before, and shift the wedges, that is, put a thick one in the place a thin one occupied before, screw the plate back in its place, and you have the instrument in its proper place for cutting a left-handed screw. Ti will be seen by ani inspection of fig. 8, that the end a is lowered down the thickness of one thread, and the other end b raised a little to make the ihreads or indentations on triat side perfectly agree with its opposite die. The shape of the wedges are given (a thick and a thin one) so as to keep the die firm in its place between the plates, and to give it its proper inclination; the other die is made to fit and slide nicely in the Sir,—I herewith forward you the destock and between the plates, so as to be scription of an apparatus, contrived by inoved onwards by the screw, fig. 4, as it me some years since, for cutting a screw cuts. By having another set of wedges, of any number of threads, and left or so as to lower the end a, fig. 8, one-half a right-handed. The principle upon which

[ocr errors]

If you


IMPROVED HANDLE FOR STREET WATER-POSTS. the screw is formed is the same as that the cutter at right angles to the groore in which was employed by the late Mr. the wood E. This being done, in order Allan for cutting a trne screw for his to cut a screw with any given number of diviiling-engine; but the machine now threads per inch, calculate trigonometri. described will perforin what his would cally what angle the thread must form nut, viz. cul a screw of any length. with the axis of the required screw.


Then the culter to this angle by the gra. Description of a Machine for Cutting duations on the upper half of the head A, correct Screus.

and fix it by screwing up the screw at CCCC is a frame of metal, between

the side of the tube B. Having the the bevelled edges of which a piece of

cylinder upon which the screw is to be bos-wood E slides, in which is an angu.

cut turned crue in every respect, place it Jar nutch for the reception of the cylinder

in the notch of the piece of wood E. lipun which the screw is to be cut. The Screw it up (slightly at first against the box-wood is used in order that as soon as

cutter by means of the nut at the end of a thread is cut upon the cylinder a simi

the handle F, and turn the cylinder cauJar one inay be formed by its action upon

tiously round; ile screw will then be the wood, and by this means ensure all

formed upon it, and by degrees may be the succeeding threads to be repetitions cut to any required depth. For a leftof the primary one. Under this piece of

handed screw ihe cutter must, of course, wood a plate of brass is fastened to the

be set in the contrary direction to that end of a screw, which pässes through the

required for a right-handed one; and I handle F. The nnt G is also tapped,

should also state, that the cylinder upon and, being confined to its situation by a

which the screw is to be cut should be small screw (the point of which enters a

inserted about an inch or so into the ma. groove formed round the nut), will when

chine at the cominencement of the opera. turned ound force the brass plate and

lion, that it may have a good bearing. block of wood up towards the cutter D. I am, Sir, yours respectfully, A is a divided micrometer-head, the

N. S. Heineken. lower half of which is connected with the tube B. This tube is again fastened

Sidmouth, April 26, 1836. into the centre of the upper plate of the frame C. The upper half of the divided head A has in its centre a cylindric piece IMPROVED HANDLE FOR STREET WATERof metal accurately fitting the tube be. fore-mentioned-confined in its place by a small screw at the side of the tube B, and formed so as to receive at its extremity the cutter D, which cutter is also firmly fixed by a small side-screw.

In order to use the machine it is necessary, in the first place, to fix the cutter D at right angles to the axis of the cylinder upon which the screw is to be cui. For

of wedi this purpose, let there be prepared a cylinder of steel, hardened, round which is turned an angular groove; release the

6 sinall screw at the side of the lube B, so that the divided head A and cutter D attached to it shall be free to move round. Now insert the above-mentioned cylinder of steel in the notch of the box-wood E, so that the groove in the steel cylinder may receive the cutter D. Gently force Sir,— Within the last twelve months it up against the cutler by turning the the New River Company have adopted nut at the end of the handle. Now turn the commendable precaution of prevent round the steel cylinder, and it will place ing a needless waste of their water, bý


الام ::


379 Locking up the water-posts throughout structed of three cylinders, upon one of the inetropolis; but they have not been which I imposed the type, and upon an. at all liappy in the plans they liave re. other come woollen cloth; the remaining sorted to for this purpose. In the first one was for the purpose of applying the place, à ring was fasiened on the octa- ink. I found it to answer very well for gonal at the top of the post, and a chain illustrating the principle of rotary print. bronght down from it to a staple fixed at ing; and a correct impression was given the side, and secured by a padlock. This with any degree of speed hy turning à was, for many reasons, a very objection crank. I employell both moveable type able arrangement, and has been recently and bent stereotype plates. Upon visit. superseded by another modification, un- ing London, however, I found ihe latter fortunately not much better. In the pre- in use; but no one with whom ( caine in sent contrivance the octagonal ring is at- contact seeined to have conceived the tached to à long arm which terminates in idea of the former, nor was it any wliere a chain-link, and eye to embrace the in operation. My discovery was comstaple. . When water is required, the municated to a number of friends here; padlock has to be opened, the ring, arm, and in London, I mentioned it to Dr. &c. taken off, and a key placed on the Birkbeck, Dr. Bowring, Mr. Spottiswoode, octagon pin, when the cock may be Mr. Bramah, Mr. Clowes, Mr. Murgan, turned.

and others, and I directed a respectable Annexed is a rough sketch of a con- firin of solicitors to take the preliminary trivance, that I am inclined to think steps for securing a patent right. This, would be much more convenient, and far however, I declined prosecuting to the more advantageous, than any of those close, partly on the score of the expense, that have been hitherto einployed. ab is and partly from the interference of proA curved iron arm or lerer permanently fessional pursuits. When I mentioned fixed to the plug-head of the cock, and my proposed method to Dr. Bowring, he hinged at a, with an eye to embrace the said that it had been long in use; and slaple at b; the padlock makiny all fast. was only convinced of his error by in.

When water is required, the padlock specting, alorg with me, the improved being removed, the arm is raised to the printing-machine at Mr. Hansard's, Pa. position shown by the dotted lines, and ter noster-row. Mr. Clowes, while he ac. forms of itself a handle, by which the companied me through his establishment water may easily be turned off or on at near Stamford-street, admitted the appli. pleasure. By an arrangement of this cability of my meihud, but contended kind, no key, except that to the padlock, that the improved machine then in use is required to be carried by firemen and was adequate to meet every demand. others who have occasion to use the water, It is quite obvious, that an arrangeand a cock so secured may be opened in ment whereby a revolving cylinder is less than half the time taken up by the covered with type must produce results three-fold operation at present required. very much superior even io thuse of the

The foregoing sketch exhibits the mode very best engines now manufactured. of applying this principle to posts at pre

The establishment of the Times newssent standing; but in any new Castings paper has been noted for its efficiency, it might be applied in a more elegant yet a rolary-machine would as much exmanner.

cel that which is employed therein, as I remain, Sir, yours respectfully, the latter surpasses those ordinarily in

WM. BADDELEY. use. This will be evident if we consider, London, August 23, 1836.

first, that the area of the form of type

employed in the existing improved maDR. M'CORMAC'S ROTARY PRINTING

chine does not perhaps exceed a fourth of that of the cylinder by which the paper

to be printed is applied to the surface of Sir,—While looking over your valua- the forın; second, that the cylinder in ble journal for July, I find at p. 271 the

question, in place of continuously revolv. announcement of a patent rotary print- ing, has its motion reversed,* in order to ing-machine. Such a one occurred to me several years ago; and about five

* Onr correspondent is in error here ; the cylin

ders revolve continuously, but the bed upon which years since, I had a small machine con- the form of type is laid reciprocates.-Ed. M. M.


[merged small][merged small][ocr errors]

permit the form to resume its place, by chase, with four sides, two of which were which the area of the latter is virtually suitably curved and applied to the cylinreduced to one-sixth of that of the cylin- der by means of screws. The size of the der; and, third, that the existing im- chase was to be that of the half sheet; proved machine only admits of a limited and the types were to be duly secured in degree of velocity; whereas that of the it by lateral screws. In this manner I machine which I propose is restricted in locked together, and applied to my little this respect only by the capacity of the cylinder, an advertisement casually taken materials, and an equable rotary motion from a printing-office, which sufficed, would permit considerable rapidity.—but with my limited mechanical means, to if we only say six times that of the ordi- show the practicability of the principle of nary improved machine, it will, if added rotary-printing. The chase, with the to the increased area, produce an increase contained type and lateral screws, I of rapidity virtually twelve times greater. showed to several individuals in London, It is obvious, however, that a duplicate and finally left it at the National Repoengine might be so arranged that both sitory, Charing Cross. sides of the sheet might be printed al

I remain, Sir, most at the same instant; hence the ulti

Your very obedient servant, mate rapidity will be about twenty-four

Henry M'CORMAC, M.D. times that of the existing improved ma

August 24, 1836. chine. As the improved paper-inaking machines can turn out sheets of any re

LUBRICATION BY WATER. quired length, such would probably answer better in the proposed rotary print

Sir,-! perceive in the report of the

Times of the proceedings of the scientific ing-machine than the small sheets now

meeting at Bristol, that Dr. Lardner sugin use.

gests placing watering-pots before the The bent stereotype-plate I found in

wheels of a train of railway-carriages to reuse when I went to London, but I was duce the friction. The fact of a train runpreviously ignorant of the fact.


ning lighter on a wet day is well kuown lo would have supposed that the utility of

every engine-driver; and it occurred to ine extending the plates over the whole

to avail myself of the water leaking from cylinder would have been obvious, but

tbe boiler or tender, passing it, in the first in Mr. Clowes' machines the plates instance, into iny ash-pan (ilescribed in covered but a small portion of it indeed ;

No. 680), from which the excess drops in and the motion, in place of being a con- a sinall jet behind the engine-wheels; tinuously revolving one, alternated back

thus the engine travels over the dry, and ward and forward, by which half the area the tender and train over the wetted part of the cylinder, or, in other words, half the

of the rail. In the event of the builer time was lost. It might have also been thought that the superposition of stereo

being su tight that the leakage would be

insufficient, two small iubes, with regutype-plates on a cylinder might have lcd to the superposition of moveable types

lating cocks, should pass from the lender

or cistern, and discharge a small jet ou also ; but it was not so, at least it was no the rails as the train passes along. I where in use, nor did I ever hear of it

shall feel obliged by your insertion of before the conception arose in my own this letter in your earliest Number in mind. The method by which it occurred order to advance my lille to the priority to me that this inight be realised was

of this useful adaptation of what would simple enough; the type must be wedge- be otherwise lost water. shaped or pointed, or the spaces which

I remain, Sir, separate them must be so. I chose the

Your obedient servan!, latter in the rude inachine which I had

W. J. Curtis, constructed, for the simple reason that I Deptford, August 29, 1836. had no means at hand of procuring wedge-shaped type, or for having them cast, It is quite clear that no other con

MR. MACKINTOSH'S ELECTRICAL THEORY trivance will avail to secure the neces. sary parallelism of type when applied to Sir,-Mr. Mackintosh inforir's me in the surface of a cylinder. I proposed to his last article (No. 681) that I jabour secure the type together by a small iron under a mistake with regard to his elec


MR. MACKINTOSH'S ELECTRICAL THEORY OF THE UNIVERSE. 381 trical theory of the universe. It is, he A few sparks perhaps will fly off from thě says, no where stated to be in accord- sun after the collision, which will after: ance with Kepler's laws," &c. I shall wards be manufactured into so many quote the passage I alluded to, which is comets, and they will in proper time be given in No. 645, p. 233 :

converted into regular planets, taking

their proper places in the system in rear " We have no data whatever which would

of the Herschel planet. Now here I can. enable us even to attempt to fix the time occupied in accomplishing these vast operations

not help remarking, that Mr. Mackin: of nature; each specific change in bodies of

tosh's theory has some resemblance to such immense magnitude must require periods

what is commonly styled the fanciful of vast duration—compared with which the

theory of Buffon. age of human records is but as one day. We

Mr. Mackintosh seems to think that his are assured by experiment that the attractive theory derives great support from the esa and repulsive forces of electricity follow the tablished fact of the moon's secular accesame law as to its intensity, that is, the in- leration. That the motion of the moon verse law of the squares of the distances. for some thousand years back has been Let this be compared with the laws of Kepler, continually accelerated, is an undeniable and we think that the conclusion cannot be

fact; but I am afraid it will add little in resisted, that the motion and distances of the

support of the electrical theory. Halley, planets are regulated and determined by this powerful and all-pervading agent.”

by comparing the ancient Chaldean ob.

servations with those of the Alexandrian, I certainly thought, and I think so and those of the Alexandrian with the still, that Mr. Mackintosh meant to infer, Arabian, and, lastly, the Arabian with that the effect produced by the agency of those of modern times, discovered that the electricity would produce a similar result moon's mean motion was a little acce. in the motion of the planets to that lerated, amounting to eleven seconds in which is said to be produced by Kepler's a bundred years, and how to account laws. Mr. Mackintosh, however, now for this perplexing fact upon the principles thinks proper to deny this. But Mr. of universal gravitation, resisted the united Mackintosh must be aware that Newton efforts of some of the greatest astronuhas rigidly demonstrated the truths of mers, La Place at last discovered the Kepler's laws, and that they form three cause of this seeming anomaly in a dis. strong pillars in support of the Newtonian sertation he read to the Royal Academy system of the universe; so that if the of Science in 1785. He there show's electrical theory is at variance with Kep. " that the acceleration of the moon's ler's laws, it is equally so with the New- mean motion necessarily arises from a tonian system. Then, Mr. Mackintosh, small change in the eccentricity of the on this head we understand one another. earth's orbit round the sun, which is now

Again, Mr. Mackintosh informs me, diminishing, and will continue tu dia that if I will examine bis system more minish for many centuries by the mutual attentively, I will perceive, 's that so far gravitation of the planets." He deterfrom the momentum of the planets being mined ihe diminution in a century to be extinguished, they are supposed to be ac- 11.135 seconds; he had previously de:. celerated; because it is assumed they termined that a like anomaly took place move in spiral orbits, which (the orbits in the satellites of Jupiter, 6 and as the being elliptic) is the same in effect as if inotions of these bodies are so rapid, in they were rolled down an undulatory in. the course of a few years many synodical clined plane. I beg to

periods are accomplished, in which the Mackintosh that I have duly considered perturbations, thus arising from their all this, which is deducible from the mutual actions, return again in the same equation dv2=D V?, that is, if D and V2 order.” And such synodical periods have be constant, and d a variable diminishing been since verified by actual observations. quantity, v2 and..v will continually La Place's great rival, Lagrange, arrived increase. But what becomes of the mo. at a similar result, and demonstrated mentum when the planet comes in col- that all these sinall perturbations go lision with the sun? It will produce an through all their varieties, swelling to a increased velocity in the sun, and both maximum and then diminishing to 0. will then move on with the same velocity. These great astronomers have also de

assure Mr.

« iepriekšējāTurpināt »