Sidebilder
PDF
ePub
[subsumed][merged small][merged small][graphic][subsumed][ocr errors][subsumed][ocr errors][ocr errors][ocr errors]

SIR,-Whatever has for its object the preservation of existence in perilous circumstances, is entitled to some consideration. The above figures represent the structure and manner of wearing what I call a Marine or Bathing Cravat. It is merely a cylinder of leather, water-proof, three inches in diameter, sufficiently long to surround the neck and fasten behind with a buckle or clasp. Within the tube or cravat, at intervals, represented in figure 3, are eight pieces of cork-wood, such as bungs, fixed in the following manner: In the circumference of each a groove is cut, and, when placed at the proper,

distance from each other, a waxed cord is drawn over the leather upon the groove which fastens the cork and retains it firmly in that position. The advantage of this separation of the cravat is, that if water should insinuate itself into any of the divisions, it would be cut off from communicating with the others. To render the leather still more impervious, it might be varnished inside with elastic gum. A tube of this dimension exerts a buoyancy of about five pounds, sufficient to render unnecessary any exertion to keep the mouth and nostrils above water. By the use of this simple and convenient

IMPROVED PUG-MILL.

[blocks in formation]

169

which were of oak, and slightly injured. I then gave a good coating of hot limewash to every part that could be conveniently got at, and closed the work again. About the middle of March last the same destroyer made its appearance in another part of the same room, but I found that wherever the hot lime had been applied in the slightest degree, the wood had not been, subsequently, in the least deteriorated. I have not the least doubt but the application of hot lime will both prevent the commencement, and stop the progress, of dry rot in buildings. The preparation is cheap and wholesome, and easily applied. I am, Sir,

Your obedient servant,

[graphic]

SIR, Having frequently, of late, opportunities of visiting many of the brick-fields about the metropolis, and examining the various machineryused to grind the clay, I was very much astonished to see the manner in which (in despite of all common sense, not to say philosophy) the common Pugmills were furnished. I saw a long beam of heavy timber stretching out from the spindle, entirely on one side, and the horse (with every neglect for the "line of draft") labouring, having nearly as much force to exert in order to overcome the friction of the spindle against one side of the

collar in which it turns, as was neIt is cessary to grind the earth. strange that some counterpoise is not generally used (as I trust some individuals must have had sense enough to adopt it), in order to relieve the poor animal, who certainly has a very "tough job." The objection stated to me, when I proposed it in one place, was, that it would be in the way of the man who wheels the earth to the mill. This was mere prejudice, as the horse moves slowly enough through the arc of a semicircle to allow the man time to empty his barrow into the mill. But were

[blocks in formation]

this objection on proper grounds,
there might be a counterpoise fixed
in such a manner as to remove this
inconvenience. For example, the
iron rod, B, might be connected to
BF, curved as represented in the
figure, and having the metal ball, A,
attached to it, so as to slide out or
in on the rod; in order that it may
be adjusted exactly to poise the
horse-beam, BF, it could be kept
steady by a small wedge. This im-
provement, which any person might
suggest, I mention merely because
no one has hitherto (as far as I know)
laid the matter before the public.
I am, Sir,

Your obedient servant,

J. M. M-N.

ANTI-INCENDIARY COMPOSITION.

We are informed by a French Gentleman, now resident in London (No. 20, Newman-street, Oxfordstreet), that he has discovered a peculiar composition, which is possessed of the admirable property both of preventing and extinguishing fire. It is said not to be expensive, and may be indiscriminately applied to any object whatever. By means of this discovery, not only wood and cloth, but paper and straw, can be actually rendered flame-proof.

PRIZE CHRONOMETERS.

[ocr errors]

SIR, My attention has been directed to an article in your valuable Publication of the 4th instant, headed "Prize Chronometers," wherein it is declared most unceremoniously, aud as a matter of fact, that I never made a chronometer, and am a mere "dealer and chapman." Now, Sir, although, in my own judgment, I do not feel myself bound to notice this most unfounded attack of your anonymous Correspondent, yet, as you seem to think otherwise, I beg leave, for the information of such of your readers as might have been imposed upon, to say, shortly and strongly, that it is wholly false and unfounded; and I challenge your nameless Correspondent to avow himself, and attempt to prove what he has so unwarrantably asserted.

After having been actively engaged in the operative department of my business for thirty years, commencing with an and being at this moment a manufac apprenticeship of seven laborious ones, turer, to a large extent, of chronometers of all descriptions (which, I need not explain to you, includes every machine for the admeasurement of time), motive is too obvious to be mistaken, I little expected such a charge; but the and too malicious to have any effect with a discerning public. However, as you have given publicity to this attack on me, I have no doubt you will see the necessity of joining with me in calling and avow himself. on your Correspondent to come forward If he is a real workman," I shall feel little difficulty in convincing him of the injustice of his charge.

1

Having made these observations in deference to you. I must declare my intention not again to notice any anonymous attacks; and, in conclusion, allow me to remark, that your valuable Magazine would give more satisfaction to its numerous readers, if you insisted on the name and abode of such a Correspondeut as this, before you gave wide circulation to an attack on professional merit or acquirement, however humble.

I remain, Sir,

Your obedient humble servant,
J. M. FRENCH, {

Royal Exchange, June 9th, 1825.

In inserting the letter referred to by Mr. French, we did not act so unad visedly as he seems to suppose. We had heard that, among "real workmen," it was a subject of very general complaint, that they were outstripped in the competition for the prize chronometers by masters who were not workmen; and being earnestly requested by one of their uumber, who gave us his name and address (for we did not, as Mr. French takes for granted, neglect that necessary precaution), to bring the matter before the public, by the insertion of the letter in question, we thought that by doing so we could do injustice to no one; since the necessary consequence of agitating the matter must be to silence the murmurings of the one party, should they prove unfounded, and to make more honourable the triumph of the other, should it prove to have been fairly achieved. Mr. French has met the charge of not being a real manufacturer by the most positive denial of its truth. He appeals to a life spent in the arduous pursuit of his profession; and he has, besides, been at the pains to satisfy us personally, at a visit which we made to his workshop, that he is, in truth, what all the

[ocr errors]
[blocks in formation]

Nearer approximations to absolute correctness can scarcely be hoped for, than has been exhibited in these different instances; and while they do honour to Mr. Freuch, they serve to explain why he is so unjustly an object of jealousy and animadversion to his rivals.

world gives him credit for being, a most expert and ingenious workman, But it is said, that he never made a chrono meter himself. If by this it is meant to be asserted, that he never, with his own hands, manufactured all the parts of a chronometer, and put them together, no more is asserted of Mr. French than may, with equal truth, be asserted of We subjoin, as a matter of curiosity, every other workman. A more extraorthe rate of Mr. French's Chronometer, dinary instance cannot be adduced of the No. 720, as taken at the Royal Obser subdivision of labour, and of the bene- vatory for seven months previous to its fits arising from it, than this very matbeing made the standard for computing. ter of watchmaking. No less than 34 the longitude of Madeira. The uniformdifferent classes of workmen are emity of its operation is very remarkable.

ployed in making a plain watch (see Mechanics' Magazine, vol. 1. p. 170), while a repeater requires many more; and it is owing to the excellence which each is enabled to attain in his distinct department, that this branch of art has reached such a state of perfection as it has done in this country. The circumstances by which one master manufacturer may fairly hope to be distinguished beyond others, consist in a better choice of materials and workmen, and in a more skilful combination of the different parts, however manufactured or procured; and to every praise that belongs to great eminence in this respect, we think Mr. French is most justly entitled.

"

The chronometer, No. 1640, made by this gentleman, and which gained the prize of 2007. awarded this year by the Board of Longitude, varied only one second and 85-100ths of a second, on its mean daily rate, during the whole twelve months it was on trial at the Royal Observatory; and for the last six months was reduced

of that period, the cond.

as low as 45-100ths

It is also greatly the credit of Mr. French, that his chronometers have been twice adopted as the standard in surveys made by Dr. Tiarks, by order of Government, for ascertaining the longitude of different places; first of Madeira, and then of Dover, Falmouth, and Portsmouth; and that, in both these instances, they fully sustained the well-earned reputation of their maker. The result in the former instance was particularly remarkable. There were seventeen other chronometers employed on the occasion, and the standard gave the same time as the mean of all these seventeen, within two hundredths of a second.

Mr. French has once more entered the lists (which, it is worth observing, are open to every one, whether master or man) for the prizes to be awarded next year; and from the first monthly report (for May) now before us, it appears that out of forty-eight chronometers ou trial, one of his, No. is that which has varied the least; the greatest variation from its mean daily rate being one second and 3-10ths of a second,

20

3912'

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

172

SOCIETY FOR THE ENCOURAGEMENT OF INVENTIONS.

rescuing inventive genius from the numerous difficulties by which it is at present surrounded; and that nearly all the more eminent men of science in the three kingdoms have promised to give the Association the benefit of their counsel and assistance. From the following copy of the Prospectus which they have issued, it will be seen more precisely what their views are, and what the success which they anticipate.

PROSPECTUS.

The prosperity of nations depends on nothing more than the encouragement of the inventive powers of individuals. It is to invention we are indebted, not only for all the arts, but for the most valuable, because the most original, descriptions of public and private wealth. Every other species of property is something gained by individuals from the common stock; but the productions of invention are positive additions made to that stock by individuals.

That Great Britain has been prosperous beyond all other countries, is to be ascribed, however, less to the express encouragement given by her institutions to useful inventions and improvements, than to the fewer obstacles which genius has had to encounter on British ground, and to the profits of successful adventure being greater than in foreign states. It is not speaking too severely of our existing laws on the subject of patent rights, to say that they are not among the least absurd and injurious portions of that mass of unwise legislation respecting trade and manufactures, which the more enlightened policy of modern times is now engaged in effacing from the Statute Book. They have operated solely as dead weights, and in no respect as first movers; nor can it be doubted that, but for these laws, the British people would have been now much farther advanced than they even are in the arts of peace and in genuine prosperity.

Instead of genius being cherished and rewarded as it deserves, it is matter of notoriety that it but rarely reaps the harvest of its own sowing,

and that many designs of the best promise are, in consequence of the difficulties which the existing state of things opposes to their development, altogether lost to the world. Is an inventor humble and poor, who is there to advise and befriend him? He has no access to men of

science-no patrons among men of wealth; he cannot himself defray the heavy expense of securing by patents the property of his invention, nor even, in many cases, the cost of those preliminary experiments necessary to determine its real value. He seeks among strangers for pecuniary aid, perhaps too for scientific advice, and either falls into the hands of persons who plunder and then forsake him, or, from a natural reluctance to give his entire confidence to a stranger, makes such an imperfect revelation of his plans, that nobody can be induced to patronize them. Is an inventor, on the contrary, in easy circumstances? Although able to pay all the expenses of experimental investigation, he has rarely the conveniences requisite for conducting it; and from not subjecting his designs to this necessary test, he finds, too late, that they are either not worth prosecuting or visionary. Even when he has acted most advisedly in taking out a patent, it is seldom that he possesses the facilities requisite to turn it to a profitable account.

It will be the object of this Society to remedy the various evils here pointed out; to rescue mechanical and scientific genius from unmerited neglect and oblivion; to stimulate the energies of those to whom success has hitherto appeared hopeless; to give to persons of all classes every possible chance of profiting by their inventions and improvements, and thus to call into life and full activity the whole inventive powers, not only of the native-born British subject, but of all who may choose to make this country their home.

[ocr errors]

The Society propose to make such pecuniary advances as may be neces sary in each instance; to establish workshops, where trials and experiments may be made with secrecy and dispatch; to procure the confi

« ForrigeFortsett »