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all my arguments are built upon that im the moment of transferring power ; but it portant element in practical mechanics, becomes a mere fiction when the deficiency though to the mathematician a most trouble is proved to exist—when it is proved that some one. If your correspondent will take the first mover cannot give over to the fly, the trouble to look back, and read over again through the medium of the crank, all the these experiments, about which so much has power, without any deficiency. been said, he will find that they are intro At page 71 in your last Number is given duced with the observation, that the crank, a paper read at the Cornwall Polytechnic considered in the abstract, and without re Society, (these Cornwall engineers will cer. ference to friction, might, for all the pur tainly make your mathematicians go mad,) poses of my experiments and the line of ar giving an account of a large steam-engine gament made use of, be supposed incapable being applied to pump water to work water. of losing power; and hence arose the neces wheels. This idea is not altogether new, sity that my explanation should fully show, for Watt originally employed steam-engines in the most practical manner, my meaning without a crank for that purpose ; but it of the words “loss of power," but which he was reserved for the present day, and for a considers cannot properly be called other Cornwall engineer, to demonstrate by actual than a mechanical deficiency of effect. As I experiment, and on a sufficiently large scale, said before, I am perfectly willing to sub. that it is much more economical to pump scribe to this; but your correspondent must water for that purpose by steam, than to admit, that if my experiments prove that a make use of a crank to the engine. Not. “ mechanical disadvantage," and a deficiency withstanding the well-known loss which of effect, does exist in making use of the takes place in working water-wheels, this crank, or any other description of shifting mode had an advantage over the crank, in leverage, which would not take place if the the proportion of 14 to 10. What, therefore, crank were removed, then in practice the must the mechanical deficiency of the crank deficiency should be considered due to the have been? Nearly one-half more work was, crank alone, and that it is a matter of the it appears, performed with a bushel of coals first consequence to remove it, if practicable than when a crank was made use of. And to do so. And if the practical mechanic, this, too, though there was a considerable seeing this, and endeavouring to give motion deficiency of effect in the working of the to machinery without the intervention of a water-wheel. crank, has an idea he can perform a greater Your correspondent's mode of making quantity of work with one bushel of coals, nice distinctions is amusing. In reference by so doing, than he could with nearly two, to a quotation from your Aberdeen correwhen using the crank, I hope your corre spondent he states, that instead of saying, spondent will also admit, that all the gentle. poi that one engine had nearly double the men who wrote on the subject, in favour of power of the other," I said, “your northern his views, and considered such a person correspondent admitted that the crank en. (and expressed themselves to that effect) as gine did not do one-half the work of the unacquainted with the first principles of me other." I will leave it to the mathemati. chanics, should withdraw such assertions, cians to discover the difference : certainly, and make some excuse for having so incon there was no misrepresentation or exaggerasiderately expressed themselves on a subject, tion in the case, on my part, although I without having made themselves better ac quoted at the time from memory. quainted with it.

With respect to a misrepresentation, or Your correspondent mentions that, to re rather, I should call it, an erroneous verstore the mechanical disadvantage, it is only sion, which your correspondent has given of necessary to procure a fly-wheel, the mo. my experiments, it is necessary to say a few mentum whereof will restore any deficiency words. of effect to the crank. He will find, how. The facts stated in these experiments, (p. ever, by referring to my experiments, and 259, vol. xxxv.,) your correspondent does to my recapitulations of them, that I showed not question ; it is only the conclusions that want of momentum in the first mover drawn from them that he quarrels with. was a cause of mechanical deficiency in any The two weights of 56 and 28 lbs. were system of shifting leverages. How would moved over a space of 6 inches by a power he give momentum to the steam when ap of 50 lbs." moving through a space of 4 plied as a first mover? The beautiful idea inches perpendicular. This was done, be it of a fly, by its momentum, accumulating remarked, by a shifting leverage, so arranged, and storing up power in one part of the that the power applied by means of the changcrank's movements, to be given out where ing leverage was equivalent at the changes to necessary, would be very well, if experi. the work required to be done. The weight ments could prove that no deficiency of ef of 56 lbs, had to be drawn 2 inches, with the fect took place by the shifting leverage at full effect of the first mover moving 2 inches,

and 28 lbs. to be drawn 4 inches with that inches, while in the latter case only 28 lbs. power reduced one-half by the lever, and could have been drawn. moving 2 inches more. Your correspondent Let us for a moment longer confine our admits that a weight representing the aver attention to this experiment, and connect it age of these numbers, combined with the with the non-momentum apparatus, and see spaces passed over, namely, a weight of 37+ how the matter stands. Making use of the lbs. could not be drawn over the same space shifting lever or cross-bar on the table, and of 6 inches by means of the shifting leverage. the friction-rollers, the greatest weight which Now, it is only necessary for me to prove, can be drawn by the spring beyond the line by the facts stated in that paper, that a mark on the table is 28 lbs. ; by the limits weight of 374 lbs. was actually drawn over the experiment is confined to, no greater that distance with a power represented by weight could pass that line. Now let us re50 lbs. moving through a space of 4 inches, move the cross-bar, and attach the short when there was no shifting leverage, and lever under the table, and fix the spring to when the power exerted was uniform and it, in the same position as before the weight constant. This was performed; and had of 50 lbs. had been placed. The leverage in your correspondent quoted the passage which this latter case will be to the leverage where I now give, and which I complained that he the cross-bar was made use of in the pro. suppressed, or did not give a correct version portion of 4 to 3. We have the proportion, of, the true state of the case would be seen. therefore, as follows : as 3 : 4 :: 28 : 37}

“ I removed the cross bar from the table lbs.; so that the spring, by means of the inwhere these experiments were performed, creased leverage, is enabled to draw 37} lbs. and put the weight of 37 lbs. on the board

over a space of 6 inches, whereas with the k, and I attached the cord which passed shifting leverage it could not draw a greater from this board k along the table, and down weight than 28 lbs. beyond the line; in the pulley to one end of a short lever of the other words, the same power being made use third order, fixed under the table: I put the of in one case, and with a shifting leverage, weight of 50 lbs. on this lever in such a po a weight of 28 lbs. is the greatest which can sition, that a motion of 4 inches given to be drawn; in the other, 375. In this case this weight or power would cause the end of

I want your correspondent to admit nothing, this lever, to which the line aforesaid was and I challenge and defy him to question the attached, to move 6 inches ; by drawing back truth of the experiment.

“ Oh! but," says the board k, with the weights of 37 lbs.

my opponent, “recollect there is no steam thereon, a few inches, this board and weight consuming when the motion is retarded, and was moved over a space of 6 inches."

that it is in proportion to the work that it is Now, was there any thing imaginary in consumed." I do recollect this very well ; this experiment? On the contrary, it is an and I also recollect, that a much greater experiment which, by the very conditions on

quantity of steam will be required to make which it is expressed-by the limitations

the same quantity of work be done as when given, render a practical trial unnecessary ; the shifting leverage is away. for all that I require your correspondent to I am not certain whether your correadmit, and which he does not call in ques spondent may understand this explanation ; tion, is, that the weight of 37 lbs. could not, but if your readers can, I am perfectly satiswhen the shifting leverage was made use of, fied. I say I have doubts of his understanding be drawn 6 inches. It will be observed, it ; and I have cause to think so, when he that 28 lbs. was the greatest weight which states that I am placed in a dilemma by an could be drawn when the cross-bar was

experiment he describes. Why, in all the made use of, and brought up to the stop experiments with the spring, the motion was by the power ; but when I increased the

confined to a space of 4 inches ; and when I leverage, when I attached the power to discovered what was the greatest quantity of the lever under the table, a motion of 4 work it was capable of performing, (the only inches to the power imparted a motion object required,) why trouble myself about of 6 inches to the end of the lever to which

any quantity of work below it ? An engine of the string was fastened ; whereas a mo ten-horse power will do the work of one horse, tion of 4 inches * in the power gave a mo or any number under ten, but will not do the tion of 8 inches to the end of the cross

work of a greater number ; but he wishes to bar, making use of the shifting leverage to build a calculation on the smallest quantity which the string was fastened. It is not ex of work the engine can do. The problem traordinary that, under the former circum

reminds one of an ass race, where the beast stances, 37 lbs. should have been drawn 6 last in wins the day. I hope he will not inStrictly speaking, it was a motion of 2 inches

troduce the principle in the present discuswhich gave a motion of 4 inches to the end of the sion, and contend, by such dilemmas, that cross-bar; but as this is the same proportion, it can make no difference, the line being made fast to the

the person who has the worst of the argucentre of the cross-bar.

ment is the most successful.

Your correspondent has a curious mode selves,) that is to say, the spikes themselves of reasoning. He says it would be absurd are closer together in each row in proporto suppose that 74 lbs. could be drawn 3 tion to the distance it is situated from the inches, because 56 lbs. was, by the terms, first row, or in other words, the first row the greatest weight which could be drawn; contains the least number, and the last row and at the same time he says, it is quite the greatest number of spikes or studs, and practical to do it by proper arrangements. the intervening rows a number in proportion No doubt it is ; but I required the weight to their distance from these two extremes. to be drawn 6 inches, and 37 lbs. was the At the lower part of the cylinder there are greatest weight it could be done with, for a three boxes placed at equal distances apart, short distance.

which each contain an adjusting plate hung Your correspondent asks me whether, in upon a hinge, and capable of being moved a steam-boat, where two engines are used, to and fro by a screw. These boxes are used and two cranks at right angles, and no mo to regulate the fineness or coarseness of the mentum, (as he says,) is required, I contend pulp and small pieces, by being placed nearer for a loss of power? I answer,—Without to, or further from a wooden conical roller doubt, I do; and exactly to the same amount placed within the cylinder, which has a numas if there were but one crank : and although, ber of spikes, or studs, projecting from as at present constructed, the double crank its surface, which are arranged in precisely cannot be dispensed with, it is on many ac the same way in every respect as the spikes counts a most objectionable mode of work upon the cylinder ; bat upon this conical rol. ing.

ler, there are, besides the spikes, or studs, I am, &c., M. two rows of knives, each row containing four

knives, which are equidistant from each

other, and used to remove the pulp and ABSTRACTS OF SPECIFICATIONS OF ENGLISH small pieces from between the spikes or

PATENTS RECENTLY ENROLLED. studs on the cylinder, which would otherwise John GREEN THE Younger, OF New. be liable to clog. TOWN, IN THE COUNTY OF WORCESTER, Claim.-" Firstly, I claim that combination FARMER, for certain improvements in cut of machinery which I have described as formting, or reducing turnips, mangel worzel, ing a reducing or grinding apparatus, and carrots, and other roots for food for horned also any other combination of mechanical cattle, horses and other animals. Enrolment parts for reducing, or grinding previouslyOffice, September 7, 1842.

cut pieces of roots into a pulp, and small These improvements are stated to consist: pieces, in which combination the roots are

Firstly, in the construction of a machine, operated upon by moveable surfaces, or by or apparatus for reducing, or grinding into surfaces, part of which are moveable, and pulp and small pieces, turnips, and any of part of which are stationary, and upon which those roots which are, or may be used as are placed spikes, or studs, or any other sifood for cattle and other animals, and which milar projections which will produce a like roots have been previously cut into slices, effect; and, secondly, I claim the combinaor strips : and, secondly, in the combination of tion of such reducing or grinding apparatus, this machine with other well known machinery, with other machinery or apparatus (such as or apparatus for cutting the said roots into I have described for cutting the said roots slices or strips, so that when combined they into slices or strips,) but I lay no claim shall form one machine, and perform the two whatever to this cutting machine alone.” operations simultaneously.

The patentee adds, “ that the object in The machinery which performs these two reducing these roots into a pulp and small operations of cutting and grinding, is pieces is, that they may be mixed with a very fully and clearly described, and illus portion of chaff, which makes a very econotrated by a number of well executed draw mical and nutritious food for cattle.” “ It ings. The grinding apparatus, which con is obvious," he says, “that when fodder of stitutes the principal, if not sole novelty, is an inferior quality is cut into chaff and composed of an outer cylinder, which has mixed with a portion of ground roots, it projecting from its interior surface, a num would be much more eagerly devoured by ber of spikes, or studs, which are cast upon cattle, than when the roots and fodder are it and arranged in circular rows ; the spikes, given alternately.” or studs of the first row being longer than The machinery may, he thinks, be also those of the second, and the second longer “ beneficially employed in cutting or reducthan the third, and so on-the spikes of each ing apples and pears previously to being row gradually diminishing in length as they ground in the ordinary cider mill, which recede from the first row, and each row would very much facilitate and expedite the being at the same time a proportionately less latter operation.” distance apart (as are also the spikes them JOB CUTLER, OF BIRMINGHAM, for im

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provements in the construction of the tubu speculum, which was lying on a table with the lar flues of Steam Boilers. Enrolment

concave side uppermost, he was sometime after sur

prised to observe, on removing the paper, and lookOffice, May 6, 1842.

ing at the speculum, that there was a distinct imThe inventions which are the subject of pression upon it of several lines of the print, and this patent are less “ improvements in the

that the impression was strongest in the centre,

where it is certain no contact could have taken construction of the tubular flues of steam place. As there appears to be some difficulty in boilers," than improvements in the mode giving this new phenoinenon a sufficiently distincof manufacturing tubes in general; and it is

tive name, we beg to suggest that it may very

fitly be called after its first promulgator-Moseroin the latter sense, in fact, that the most im

type. portant of them are claimed by the patentee. Recovery of H. M. S. Magnet.-Accounts from Nothing, however, is better settled than that

Sweden state that this vessel has been raised from

the bottom of the Malmo roads, by means of a diva patent which is founded on a deceptive

ing apparatus, invented by Count de Wenkerheing. title, and linked to a specification which Her inasts, sails, and rigging are stated to be in claims more than the title can possibly cover,

good condition. In the hold were discovered three is invalid (though possibly not past mend

skeletons, and the body of a man in nearly a perfect

state of preservation. The Magnet (built of oak,) ing). What the inventions are, may be mounting 18 guns, foundered in the above roads in gathered from the claims of the patentee,

the year 1809, thus making the time of her lying which we subjoin.

under water a period of 33 years.

The Papal Steamers.--The arrival in Rome of the “ What I claim, as the first part of my three steamers constructed in England for the Pope, invention, is the mode of welding iron or was the occasion of a popular feast, at which the steel tubes, by drawing them through dies or

principal functionaries of the State, the Cardinals,

and a number of distinguished foreigners assisted. between grooved rollers, when, and at the Notwithstanding the shallowness of the Tiber, the same time as, drawing such tubes or man windings of the river, and the sand-banks which drils, the mandril being a necessary and im

frequently obstruct its bed, the steamers ascended,

in four hours, a distance which generally required portant part of the mechanical apparatus in nearly as many days. producing the welding.

Continental Barbarism.-The Moniteur des Che“ Secondly, I claim the welding of iron

mins de Fer states that nearly one-half of the or steel tubes by hammering upon a mandril,

labourers employed on the Vesdre Railroad are fe

males, who are preferred by the contractors to men at the same time I am drawing the tube for works of importance, from their superior dofrom the fire along a mandril, so that the

cility, strength, and courage. " The country of tube is welded on and drawn over a mandril

Liege has," it is said, "this peculiarity, that the fe.

males undertake all those works which require at one process.

superior skill and application that in other coontries “Thirdly, I claim the application of either

are reserved for men." iron or steel tubes when coated with copper,

Mines and Minerals of the United States.-The

production of iron, in 1840, amounted to 286,903 brass or other alloys of copper, in the con tons, in which 804 furnaces were employed ; of bar struction of tubular flues for steam boilers. iron the production was 197,233 tons, in which 795 “ And Fourthly, I claim in the construc

forges, &c., were employed, the consumption of fuel

for both these branches being 1,528,110 tons, while tion of tubular fues of steam boilers, the the amount of capital invested was 20,432,131 dolapplication of welded iron or steel tubes, lars, and the number of hands employed, including which have been drawn through a circular hole

mining operators, 30,497. The production of lead

amounted to 31,239,455 lbs., which employed 120 or die, or between rollers, and which have

smelting-houses, 1,017 men, and an investment of been drawn over a mandril, for the purpose 1,346,756 dollars. The production of gold was vaof smoothing the external and internal sur

lued at 529,605 dollars, employing 157 smelting

houses, 1,046 men, and an investment of 234,325 faces of the tubes, and for regulating the

dollars; and the production of all other metals at thickness of the metal.”

370,614 dollars, allording employment to 728 men, with an invested capital of 238,950 dollars. From the coal mines the products were 863,489 tons anthracite, and 27,603,191 tons bituminous; in the former of

which there was invested 4,335,602 dollars, and in XOTES AND NOTICES. Imprinting without contact or agency of Lighl.

the latter 1,868,862 dollars. From the salt mines Mr. Breguet the celebrated watchmaker, has ad

the produce was 6,179,174 bushels, in the raising of dressed a letter to the French Academy, in which

which 6,998,045 dollars was expended, and 2,365 referring to the discovery of Dr. Moser of Konigs

men employed. And the value produced from the berg, (see Mech. Mag No. 992, and p. 156,) that

granite, inarble, and other stone works was 3,695,884 the figures of objects can be transferred from one

dollars, employing 7,859 men, with an invested ca. surface to another without contact, or the agency of

pital of 2,540,159 dollars. light, he states, that he has frequently seen on the polished inner surface of the gold cases of watches,

INTENDING PATENTEES muy be supplied a distinct impression in reverse of the name of bis house, which had been transferred from the en

gratis with Instructions, by application (prostgraved letters, on the covering of the works, which paid) to Messrs. J. C. Robertson and Co., did not touch the case. Our friend Mr. Prosser of Birmingham, has also informed us (before the an

166, Fleet-street, by whom is kept the only nouncement of Mr. Breguet's communication,) that

COMPLETE REGISTRY OF PATENTS EXTANT having thrown a newspaper loosely on the top of a form 1617 to the present time).

LONDON: Edited, Printed, and Published by J. C. Robertson, at the Mechanics' Magazine Office,

No. 166, Fleet-street. --Sold by W. and A. Galignani, Rue Vivienne, Paris;

Machin and C 7 mDublin; and W. C. Campbell and Co., Habiburgh,

MUSEUM, REGISTER, JOURNAL, AND GAZETTE.

No. 998.]
SATURDAY, SEPTEMBER 24, 1842.

[Price 6d. Edited, Printed and Published by J. C. Robertson, No. 166, Fleet-street.

Double.
READMAN'S PATENT IMPROVEMENTS IN BAROMETERS.
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VOL. XXXVII.

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