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ON AEROSTATION.

ON AEROSTATION.

307 efficient manner. The wear and tear of of his liberation-say, for instance, a tools and machinery is also considerable; bushel for getting drunk, a sack for inthe repairs amounting in the mill worked subordination, and so forth. at Giltspur-street Coinpier to 201. a year, and this is in addition to a miller and two assistants. It has heretofore been deemed imprac

Mr. Editor, -If the following remarks ticable to grind and dress simultaneously;

possess sufficient merit to entitle them but we have been informed, that all the

to a place in your popular Magazine, a millers who have seen Mr. Hebert's ma- weekly peruser of it will feel happy at chine have entirely changed theiropinions seeing them inserted in one of your forthin this respect, the flour produced by it he

coming Numbers, in the hope of their ing unexceptionably good; and it is per- drawing to this wonderful art the attenhaps worthy of remark, that owing to the

tion of some more opulent, learned, and grinders being entirely metallic, there is scientific person than no possibility of having gritty flour from

Yours, &c. them, which is sometimes excessively un

OMRI. pleasant in bread made from four pro- Upwards of half a century has elapsed duced by the ordinary mill-stones. It since the introduction of aerostation ; appears, however, from the specification essays on which have from time to time of the patent, that the invention does not appeared in the Mechanics' Magazine ; consist in the material of which the ma- but although I differ in opinion with chine is formed, but lies in the mechani- most of the writers of those essays, parcal arrangements, which are defined to

ticularly the bird-fancier, I shall not be these, if we recollect rightly:—The here make any remarks upon their lucugrinding and dressing of wheat, or the brations, controversy not being my obreduction and separation of other sub- ject, but a desire to ascertain the cause stances, by means of a single machine, in Why, when almost all other arts and which the grinding and dressing opera- sciences are progressing towards perfections are conducted upon one continuous tion, the art of flying remains stationary? surface; or wherein the meal, as it is pro- Every succeeding attempt is limited to jected from the circumference of the merely ascending and descending where grinders, is received into a sieve whereon and how the adventurer best can, not it is dressed. The patentee seems to give where he would; all his other movements the preference to metallic surfaces on the being “ the sport of winds--scorning ground of his having made great improve- the guidance of man.”

Is there any ments therein, especially as relates to the sufficient reason why the art of voyaging easy means afforded of giving the grind- in an element far less dense than water, ing surface an unusual degree of truth; should not be performed with the same and that kind of roughness which so precision, safety, and rapidity, as on land nearly approximates to the French burr- or water? stone, as he expects will lead to the en- A paragraph lately went the round of tire abandonment of the latter. An ex- the papers, and appeared in your Numample of the application of burr-stones ber of April 16, stating, that Dr. Amge to these patent “ four-makers" is, how- had read an essay at the French Institute, ever, given in the specification, as the endeavouring to

prove that balloons invention equally embraces them.

might be guided by means of oars inIt has long been anxiously desired by flated with gas used in the car; but as I philanthropic legislators, that a substitute consider this to be merely a renewal of might be found for the horrid and de- Montgolfier's attempt, with very little grading punishment of the lash. Now, amendment, I shall only here remark we are strongly impressed with the idea, that, if I understand the learned prothat a machine of this kind, but of the fessor rightly, such a contrivance cannot size described in our previous Number answer the purpose; that is, if he means (665), is admirably adapted to effect the after the manner of a boat towing a ship, object in view, as the offender might because a boat to tow a vessel or raft thereby be easily made to atone in con- must be placed on a line in advance of finement for his offence, by grinding á the object to be towed. Now to effect given quantity of corn, as the condition this, either the car must be elevated from

308

LOCOMOTIVE-ENGINE EXPERIMENTS.

its present position), or the balloon must descend to a level with the car; but how either could be retained in such a position, I am at a loss to conjecture ; ! should as soon expect to see a ship steered by the rudder of a boat that was towing at her stern, as to witness a balloon, driven, perhaps, by a strong current of air, guided by any puny effort that could be made in the car.

I come now to inquire into the failure of the practical aeronauts of the present day (one of whom is said to have made upwards of two hundred ascents), who, with improved materials of every description, appear to have profited nothing by experience-balloons being now as nearly similar as two things can be to what they were when first invented. Mr. Green, who manufactures his own cloth, has, indeed, announced his intention of making a balloon of sufficient capacity to carry up ten persons. This enlargement appears to me to be neither inore nor less than an expensive perseverance in misconstruction; for, viewing it in a homely light, who would feel disposed to extol the abilities of a housewife com. petent to make

pudding for two persons, because, on being furnished with a sufficiency of materials, she made one capable of satisfying ten ? Nevertheless, no one can deny but that courage, perseverance, and expense, have been displayed in the cause. All that has been wanting to the complete success (probably) of the art of flying, is a little of the same inventive or creative faculty to which we owe the steam-engine, the power-loom, and a hundred other valuible improvements.

After a repetition of descriptions, such as we have been favoured with by aerial voyagers for the last fifty years, viz, a view from the clouds of the striking beauties of boats, bridges, and buildings; canals, churches, and crowds; docks, ditches, and drains; ruts, rivers, and roads; vessels, verdure, and valleys, such views as any person may parallel when he pleases, by ascending St. Paul's or the Colosseum, we come to the important announcement, that Mr. Graham is about taking out a patent for a navigable balloon. I have considered this for the last twenty years to be decidedly practicable, and, therefore, shall not, without seeing Mr. G.'s specification, or what would be still more gratifying, the bal.

loon itself, attempt to dispute or deny the efficiency of his plan for the end proposed; but, in the absence of ocular demonstration, I have no hesitation in pronouncing it an impossibiliiy, unless the present globular shape of the machine be altered.

Balloons, as the name imports, were at the first made globular, that shape being considered as best suited for con. taining the vast quantity of gas supposed to be necessary for raising the required weight. As soon, however, as it was ascertained that 2,500 cubic feet of gas were sufficient to raise a weight of 125 lbs. that quantity, and as much more as was barely necessary to raise the balloon and its appendages, should have been compressed into a different shape; but this has never yet been attempted. The same uninanageable shape has only been enlarged io gratify curiosity or conceit, arid a desire to obtain the repayment of expenses, has hitherto blasted the hopes of science. To point out more clearly the folly of attempting to make a circular machine manageable, let us sup. pose the body and wheels of a coach placed on and around a circular carriage, would it not be difficult to procure a driver sufficiently skilled to know what part of the carriage to harness his horses to, so as to give it a progressive motion, without dragging it bodily against all the rules of art? Or if a globular ship had been built, and the management of her entrusted to Drake or to Cooke, would they not have found her more inclined to turn upon her own axis than to any given point of destination ?

Should the foregoing remarks meet insertion, I may be tempted to trespass again upon your pages with a few more remarks upon this interesting subject while the mania for it lasts, which now appears to rage in London.

OMRI. London, August 1, 1836.

LOCOMOTIVE-ENGINE EXPERIMENTS.

Dear Sir,—Should you agree with me that the following fact will be useful information to your readers, you will oblige me by giving it an early insertion in your valuable publication.

Some time ago, while experimenting on a small locomotive model, I found that the application of power in the

LOCOMOTIVE-ENGINE EXPERIMENTS,

309 double-stroked locomotive steam-engine, tion affords a very convenient method of with cylinders laid horizontally, is, con- comparing the effects of central forces trary to the opinion of most engineers, with those of simple accelerating forces, very different in every other stroke; that and deserves to be retained in memory.is, when the piston is propelled forward, My method of coming at this compariin the direction in which the carriage is son experimentally, was as follows:-( moving, the force of the steam is communicated to the wheel by the pistonrod, and, of course, produces angular motion. But on the next stroke, or return of the same piston, the cylinder itself, by the pressure of the steam on the end flange towards the front of the carriage, propels the carriage in a right line forward, and leaves the piston behind the whole length of such stroke ; but as the piston-rod is connected to the crank of the axle of the wheel, it (the piston) is brought home to its situation again by the wheel every other stroke.

These considerations will fully show, that the application of the power of our

present double-stroked locomotive-eni gines is not, at the present day, under

stood. For it is evident, that the force of steam is differently applied each suc.

described a large circle upon a wall sixceeding stroke of the engine: one stroke ieen feet high, and fixed a pin in the of the engine applies the force by the centre, having drawn two lines across the piston-rod to the wheel ; while, in the diameter through the centre, at right other stroke, the force is applied, on the

angles to each other, I then took two rocket-principle, by the cylinder becom- balls (ivory billiard balls) of equal size ing the propeller, as before stated; and and weight; to the one ball a silk thread these different applications of force are

the length of the radius was attached, necessarily productive of very different

and the other end of the thread was tied effects—the one producing angular or

round the pin in the centre of the said central, and the other decidedly rectilinear

circle. One of the balls A was placed motion. From this discovery it becomes

at the top of the circle, and the other, a matter worthy the serious consideration

B, attached to the thread at the horizon. of all railway engineers, to draw a com

tal line level with the centre ; and when parison betwixt these two applications of

both were let fall at the same instant of power, in order to prove the difference of time, they invariably met at the bottom iheir respective effects.

of the circle, striking at C every time The first law of motion laid down by the experiment was tried. Now it is Sir Isaac Newton, is in the following

evident that the ball A falls with free words:-“Every body perseveres in a

motion in a straight line, while the ball state of rest or of uniform motion in a B, by the string being attached, is conright line, unless it be compelled to fined to move in a circular orbit, and change that state by forces impressed produces angular motion. And when thereon.” This is fully corroborated by we compare these two applications of more recent writers.

force (both acted upon by gravity), it is Dr. Young has the following remark clearly proved by the foregoing experion the subject of angular motion :- ment that a body A in free motion in a “ When a body is retained in a circular straight line falls through twice the perm orbit by a force directed to its centre, its pendicular height that the body B does velocity is every where equal to that in the same time; the latter being subwhich it would acquire in falling by jected to angular or confined motion, means of the same force, if uniform while the former A falls freely in a through half the radius, that is, through straight line, and consequently produces one-fourth the diameter. This proposi.

rectilinear motion. In order then to com

THE PATENT LAWS.

310 SYMINGTON'S PLAN OF CONDENSATION ANTICIPATED BY MR. HOWARD. pare these two velocities with each other, attempted to be, instantly cooled on the the velocity of A will be ✓ 64 x 16 = surface, which must therefore be very 32:0000; the velocity of B will be

extensive. The water of injection may ✓ 64 x 8 = 22.6274. These quantities,

be cooled at leisure as it were, and with therefore, as the quantities of matter are

a moderate surface; but the steam, in equal in both, must represent the quan

order to obtain a due effect on the mality of motion or momentum of each, and

chinery, must be cooled instanter. clearly demonstrates the advantage of

I am, Sir, applying force in a rectilinear direction Your most obedient Servant, over that which is applied circularly.

THOMAS HOWARD. If, then, the foregoing theory be ad- London, July 30, 1836. mitted, and of which I bave no doubt, our present locomotive steam-engines should be altered, in order to render this principle of avail at every stroke. I remain, dear Sir, yours,

Sir,—As there is likely to be ere long PRACTICUS.

some alteration in the law relating to patents, it will perhaps not be thought

out of place if I should, through the meMR. SYMINGTON'S PLAN OF CONDENSATION

dium of your valuable journal, make ANTICIPATED BY MR. HOWARD.

known an idea that has occurred to me Sir,- It is right to state that the plan

on that subject for the greater protection of condensation communicated by Mr.

of patents taken out for small machines, Symington in your last number, is pre- such as pencil-cases, pens, &c. If the cisely the same in principle or method patentee of the improved pencil-case were as that for which I obtained a patent

io attempt to punish all those persons several years back ; being, as stated in

who have encroached upon his right of my specification," essentially the with- patent, it would occupy him years, and drawal of the warm water from the then he would not be safe, for others vessel or vessels in which the vapour is

would immediately commence inaking condensed, and injecting it again amidst them again; and this, in my humble the vapour, the heat in the mean time opinion, will always be the case while having been abstracted from it.” Whe- such unprincipled men find customers ther this is effected by passing the water

ready to purchase them. Now, the simof injection through a copper worm

ple plan I have to propose for the con. coiled around the condenser, and lying

sideration of the framers of the new pa. in a cold water cistern within the frame

tent law is this :—That every patent of the engines, as in my steam-vessel, the

machine shall have the patentee's name Vesta, and shown in the drawings at

in full, and also the date on which the tached to the specification, or by passing

patent was taken out, written on some a pipe along the ship’s bottom, as pro

conspicuous place; this being done, a posed by Mr. Symington, is quite im

heavy penalty should be inflicted upon material. These latter not being new

all persons purchasing, or having in their in themselves, are not matters of inven- possession,* patent machines without the tion, but of arrangement merely.

above mark. I may add, that the process answers Trusting you will not deem the above completely, and that Mr. Symington remarks unworthy your attention, himself saw it in operation at the King

I beg to remain, and Queen iron-works, Rotherbithe, upwards of two years ago. The princi

Your obedient servant,

David SMITH. pal advantage resulting from this form of condensation over that by external

Leamington Eagle Foundry, cold applied to the steam itself, is the great reduction of the size, weight, and expense of the apparatus. In the former * When the machine does not admit of the name the liquid is slowly cooled by passing

of the patentee and date of patent being attached to

it, the penalty should extend to all persons selling along the pipe or other surface, and the or offering for sale the same without the authority steam instantly by the injection. In the

of the patentee, which written authority should be latter the steain is, or rather perhaps is

placed in a conspicuous place in the shop where patent articles are sold.

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MAGNETO-ELECTRIC APPARATUS.

Sir,- As it is my intention to construct a magneto-electric apparatus similar 10 the one represented and shorıly described by Mr. Rutter, in No. 560 of the Mechanics' Magazine, I should feel particularly obliged to that gentleman (or any other of your correspondents who possesses such an apparatus,) if he will describe more fully the various parls belonging to it. I should not thus in. trude, but that it appears to me to be an apparatus requiring considerable nicety of adjustment; as I know a gentleman who has constructed one, in wbich the compound magnet is very powerful, but which is, nevertheless, quite inactive: I in fer from this that the size of the armature, and the length and size of the copper wire forming the helices, are of considerable importance. He will confer an additional favour if he will inform me how the decomposition of water is effected by this apparatus. I remain, Sir, yours, &c.

G. S.
Birmingham, May 22, 1836.

BRITISH MUSEUM. The following petition was presented to the House of Commons on the 2nd inst. by the Chancellor of the Exchequer, and we trust it will be the njeans of securing to the world of literature and science that access to the treasures contained in the British Museum which a good classed catalogue alone can afford, for it would be futile to institute a comparison between this and a mere alphabet of names. To the Honourable the Commons of the

United Kingdom of Great Britain and

Ireland in Parliament assembled. The humble petition of John Millard, of

Arlington-street, Camden Town, Lón.

don, Showeth,

That by certain returns presented to your honourable House in the year 1833, it appears that there were in the year 1832, 218,957 printed books, 21,604 volumes of manuscripts, and 19,093 charters in the British Museum.

That several petitions have been presented to your honourable House during the present session, signed by many distinguished scholars and scientific persons, praying your honourable House that á

classed catalogue of these treasures might be printed and published in a convenient forin and at a reasonable rate.

That, in the opinion of your petitioner, such a work would be a boon conferred on the world of literature, is indispensable to all who are engaged in literary or scientific pursuits, and is infinitely superior in point of utility to any alphabetical cataloglie that could be formed of the books and manuscripts.

That Mr. John Murray, of Albemarlestreet, at the suggestion of your petitioner, has offered to print and publish, at his own risk, classed catalogues of the books and manuscripts in the Museum, if printed in octavo and sold in parts, and that by this means many thousands would be saved to the public.

That your petitioner has witnessed with the deepest regret, that in the report of the Committee appointed by your honourable House to inquire into the condition, management, and affairs of the British Museum, printed among the votes of your honouralile House of the 14th inst., ihere is no recommendation to your honourable House on the subject of elassed catalogues, nor any notice of Mr. Murray's offer.

That your petitioner has reason to be. lieve that an alphabetical catalogue of the printed books is now in course of preparation, and that it is the intention of the Trustees of the Museum to print this catalogue at the national expense, probably amounting to some thousands of pounds, to the exclusion of a classed catalogue, which might be printed and published without any demand on the public purse.

Your petitioner, therefore, humbly entreats your honourable House, that your honourable House will be pleased to direct the Trustees of the British Museum, 1. Not to print the alphabetical cata

Jogue of the printed books now in course of preparation, which in

your petitioner's opinion would not pay a tithe of its expenses, which no bookseller would undertake the risk of publishing, and which would be

comparatirely useless to the public. 2. To resume and complete the classed

catalogue of the printed books, the preparation of which it appears, from the annual accounts of the Museum, has already cost the nation more than 50001., and 10 enter

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