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suitable frame parallel to each other. To wind the cloth upon these cylinders I prepare a band of slats, which slats are united together at the ends by webbing or by a leather or other strap of any convenient width. The slats are placed at any suitable distance apart, say one inch, and they must be of such length as to allow the cloth to lie upon them widthwise, between the connecting straps. The straps must be raised above the slats to a sufficient distance to allow a space for the cloth, which will prevent its painted surface from coming into contact with the contiguous slats, when wound. For this purpose I put between the strap and each slat, a thickness of sole leather, a small block of wood, or other suitable material.

"The band of slats may be fifty or sixty feet in length, or longer if desired, and their ends are fastened respectively upon the two cylinders above named. When the painted cloth is to be operated on, the whole band of slats is first wound on one of the shafts; the end of the cloth is then attached to one of the slats, or to the shaft upon which it is to be wound; this shaft is then turned by a winch, or otherwise, as the paint is spread upon cloth, and it is thus received and retained upon the slats and suffered to remain there until the drying is completed."

LIST OF SCOTCH PATENTS GRANTED BETWEEN THE 22ND OF APRIL AND THE 22ND OF MAY, 1838.

William Chubb, of Portsea, Portsmouth, Southampton, umbrella manufacturer, for certain improvements in night commode pans and chamberpots. April 25; four months.

William Holme Heginbotham, of Stockport, Chester, gent., for certain improvements in the construction of gas retorts. April 26.

Pierre Armand Lecomte de Fontainemoreau, of Charles Street, City Road, Middlesex, for an improved method of preventing the oxidation of metals, being a communication from a foreigner residing abroad. May 7.

Thomas Ridgway Bridson, of Great Bolton, Lancaster, bleacher, for certain improvements in the construction and arrangement of machinery or apparatus for stretching, mangling, drying, and finishing woven goods or fabrics, and part or parts of which improvements are applicable to other useful purposes. May 11.

John White, of Haddington, in the, county of Haddington, ironmonger, for certain improvements on stoves for producing heated air applicable to ovens, or where heated air is required. Máy 18.

Hippolyte Francois, Marquis de Bouffet Montauban, Colonel of Cavalry, now residing in Sloane Street, Chelsea, Middlesex, and John Carvalho de Medeiros, of Old London Street, London, merchant, in consequence of a communication from a foreigner residing abroad, for certain improvements in the means of producing gas for illumination, and also in the construction of burners for consuming gas. May 14.

NOTES AND NOTICES.

The Copyright Bill.-We are glad to see that Sir Edward Sugden has given notice of his intention to move the introduction of several amendments in the Copyright Bill, which, indeed, could hardly be expected to pass in the crude state in which it was brought in by Serjeant Talfourd. Among other alterations, Sir Edward proposes to limit the term to forty years, instead of sixty,-not, we believe, an absolute term of that extent from the date of publication, as proposed in our last, but from the death of the author. Another honourable member has revived the clause of the bill of last session, now abandoned by Serjeant Talfourd himself, which provides that no author shall be allowed to dispose of more than the first twenty-eight years of his copyright; so that literature will be encouraged, not by holding out the hope of additional remuneration to the author, but by giving him the prospect of possibly enriching his descendants or "next of kin." It is needless to say that there is little chance of this ridiculous clause being re-adopted.

New Steam-Plough.-The same gentleman,—an Irish Baronet-whose steam-carriage for common roads is about to be brought forward by a jointstock company, is also the inventor of a steamplough, of similar wonder-working capabilities, for which a patent has been secured, and which will probably soon be introduced to the agricultural interest by another company. In the meanwhile, why does not the worthy Baronet carry off the five hundred guineas offered as a premium for the first really-effective steam-plough by the Highland Society of Scotland? He would have competitors, indeed, but not near so many (reckoning the hasbeens) as in the reviving of road-locomotives.

Taylor & Davis's Steam-engine.--Sir,-I have just returned from the British Alkali Works, at Stoke Prior, and have minutely inspected the new engine, described in No. 768 of the Mechanics' Magazine. The accounts hitherto published of this engine (more particularly the one inserted in the Engineers' Journal), are exceedingly incorrect, as is also the diagram accompanying my former communication. I shall furnish you as early as possible with a correct drawing and description of the engine. It is the intention of the patentees to prosecute a series of experiments with the new engine, in order to determine its power, economy, &c. &c. at present, therefore, any observations on these heads would be premature. The absnrd paragraph already noticed has caused them considerable annoyance. To correct any false impressions respecting the invention, and to enable the public to judge fairly of its merits and capabilities, is the earnest desire of the proprietors. 1 am, Sir, &c. CHRIS. DAVY.-Birmingham, May 14, 1838.

Cmplete Sets of the Mechanics' Magazine may now be had, twenty-seven volumes, half-cloth, price 11. 7s.

British and Foreign Patents taken out with economy and despatch; Specifications, Disclaimers, and Amendments, prepared or revised; Caveats entered; and generally every Branch of Patent Business promptly transacted. A complete list of Patents from the earliest period (15 Car. II. 1675,) to the present time may be examined. Fee 2s. 6d.; Clients, gratis.

LONDON: Printed and Published for the Proprietor, by W. A. Robertson, at the Mechanics' Magazine Office, No. 6, Peterborough-court between 135 and 136, Fleet-street.--Sold by A. & W. Galignani, Rue Vivienne, Paris.

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We this week present our readers with a view of the entrance to the London Station of the Southampton Railway, at Nine Elms, which we have copied from a very well-executed lithographic engraving, forming one of the illustrations accompanying a map of the line lately published.* The first portion of this railway, extending to Woking Common, a distance of 23 miles from London, commenced its work of transit on the 21st ult. Between London and Woking Heath there are five stations or places where and goods are taken passengers up or deposited. The first of these is at Wimbledon, 5 miles from town, whence passengers will be forwarded to London in fifteen minutes. The next is at Kingston, 10 miles from town, whence passengers will be conveyed in twenty-five minutes. Then we have one at Ditton Marsh, 12 miles from town, which will embrace Esher, Hampton, Hampton Court, Thames Ditton, Long Ditton, and East and West Moulsey, and will send passengers to town in thirty minutes. Three miles farther is the station at Hersham Green, which will embrace Hersham and Walton, and send passengers to town in thirty-seven minutes. Next we have the station at Weybridge Common, seventeen and a half miles from town, embracing Cobham, Ripley, Chertsey, Addlestone, Thorpe, Byfleet, and Weybridge, whence the traveller will find himself in London in forty-four minutes. Finally, there is the station at Woking Common, which will embrace Bagshot, Godalming, Guildford, and Cobham, and whence, at the ordinary pace, (calculated at twenty-four miles an hour,) the passenger will be transmitted to town in fifty-seven minutes. It is expected, that, by the 1st of September next, more than forty miles of the railway will be completed, to within about a mile of Murrell-Green; and that portion, also, between Winchester and Southamption about the same time.

In Mr. Jobbins's map, the towns, seats, and other prominent objects passed on

Map of the London and Southampton Railway, showing the situation of the stations from London to Woking Heath. Illustrated with five views from original drawings. London: J. R. Jobbins, Warwick Court, Holborn.

the line are faithfully marked, as well as the distances of the various stations from London. The lithographic views are very faithful; so much so, that the spots they depict would be easily recognisable by a stranger, in even the passing glimpse which the speed of railway transit will allow.

SUBSTITUTE FOR PUMPS IN FILLING

STEAM-BOILERS.

Sir,-Several recently invented methods of maintaining a proper supply of water to steam-boilers, have lately been described in your pages, some of which have been very justly commented upon by "Nauticus," at page 107. I think most of your readers will agree, that Mr. Whitelaw's apparatus (vide No. 769), is objectionable from its complexity, entailing great expense in its construction, with great liability to derangement. Taylor and Davis's plan, described by Mr. Evans, bears some slight resemblance to the plan which I published about four years ago, at page 277 of your 21st volume; upon this plan Mr. William Cook has suggested what he considers an improvement (vide page 83). The most simple, and the best practical method hitherto generally employed for supplying water to high-pressure boilers, has been by means of a common force-pump, wrought by connection with the engine. The principal objection to this mode of supply is, the loss of a certain quantity of power, consumed in overcoming the friction of the pump, and working it against the internal pressure of the steam, together with the impossibility of maintaining, by this means, the required uniformity of level. By the arrangement submitted as an efficient "substitute for pumps in high-pressure steamboilers," in your 572nd number, both these desirable objects are accomplished: little or no power is required for working the apparatus, and the water is sure to be kept at any definite height that may be determined upon. In Mr. Cook's communication, before alluded to, he states that, on account of the vacuum formed in the transferrer, there will be no necessity for placing the reservoir above the water-line of the boiler;" but I must beg to differ from him on this point, inasmuch as the condensation of the steam, and rising of the water from

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a lower level, by atmospheric pressure alone, will not be sufficiently rapid for the purpose, when the engine is working at any considerable speed. An elevated reservoir insures the instant condensation of the steam and filling of the transferrer, every time it is either wholly or partially emptied. My "substitute for pumps" may require a little modification to adapt it to particular employments, but I believe it will be found, in point of simplicity and efficiency, far superior to most of those contrivances for the like purpose which have been made the subject of patents.

remain, Sir, yours respectfully, WM. BADDELEY.

London, May 28, 1838.

CONSTRUCTION OF STEAM-VESSELS.

Sir, Since I last addressed you on the subject of steam-navigation, the Sirius has accomplished the voyage out to New York and home, proving that the Atlantic is actually navigable by steam-vessels from its eastern to its western shore, and, one would think, convincing a certain learned Doctor, that there is more duty in coals than he calculated upon. The Great Western, too, has made her passage out, and before this reaches you, will most probably have arrived at Bristol, the place where it was proved to demonstration that steam navigation to the United States was impossible !

It is gratifying to observe, how nearly the calculation made prior to her sailing, has been verified: she was, if I mistake not, 15 days on her passage out; and the Sirius (a much smaller vessel) was 17 days from Cork ;-proving, too, the correctness of the opinion advanced by Messrs. Seaward, in a pamphlet published by them in 1829, that for the successful extension of steam navigation, a larger class of vessels must be introduced, in order to obtain greater speed at less cost. I most cordially concur in the statement, that the vessel should be of the greatest possible length, consistent with strength. Length has been given, but unfortunately it has been at the expence of strength, as will be apparent to any one who will take the trouble to examine many of the existing steam-vessels. Instead of presenting a regular sheer, and a fair deck-line, they will be

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found depressed in that part occupied by the boiler and machinery, below a regular curve; and, if coppered, the metal will be wrinkled, which is an unequivocal proof of an alteration in the form of the vessel. This distortion is generally most perceptible in the after body of the ship, just abaft the boiler. In some old boats, on their arrival from a voyage, after a somewhat boisterous passage, the butts and seams of the wales and upper works will be found opened to a considerable extent. If any remark be made upon these appearances, the answer almost invariably given is, "Oh, these long vessels will strain." But why should they strain thus? Are there no means of prevention? Or is their length so great as to produce a strain beyond the native strength of the materials to sustain, without permanent alteration? There is, no doubt, a length which it is not prudent to exceed, in constructing a vessel; and I think from what has passed under my observation, it will be found that this limit has been very nearly, if not quite, reached upon the present mode of constructing and fastening steam-vessels. For large ships, fir ought not to be used in those parts which are intended to bind and connect the fabric together. The soft and yielding nature of this timber renders it incapable of presenting sufficient resistance to tension or pressure, without permanent alteration in the arrangement of its fibres. I might adduce some striking illustrations of this result, were it proper to do so.

The use of oak, or other hard woods, is open to objection, on account of their greater liability to shrinkage, from the great heat. This objection is greater in appearance than in reality; for, if they be properly seasoned before using, they will not be found to shrink more than soft woods under the same circumstances. Still, so far as the shrinkage extends, so much will the strength of the fabric be weakened; for it is obvious, that if the several parts be not kept in actual contact, the strength of the separate parts are not rendered fully available to the general strength. Steam-boat building bears a similar relation to the building of ordinary merchant-vessels, that building a light travelling carriage does to an agricultural waggon; and, therefore, the same principle of binding the parts together should be applied; and instead of

using fir or other soft woods in the construction of steam-vessels, nothing but oak or other hard wood should be used. The common plea for the use of fir, is its lightness; but in order to obtain the requisite strength, it is used of greater substance, and therefore the total weight of the materials is increased so as to be nearly the same as if oak only were used. I very much incline to the belief, that when thoroughly saturated with water, the fir planking is equally as heavy as oak. Another plea for the extensive use of fir for planking is, the great lengths which can be obtained. This is an advantage, undoubtedly; but it is frequently completely thrown away by the exceedingly unskilful combination of the parts. There are now in existence some of the earlier steam-boats, built entirely with oak; these vessels do not present any signs of weakness or giving way, whilst many others which have fir planking, although less than one-third their age, are yielding in several parts, and some of them either actually extensively repaired, or requiring to be so.

There can be no question but that it is contrary to sound policy to use so large a quantity of fir in the construction of steam-boats, even if cost only be taken into consideration. The difference per cent. in the prime cost between oak and fir plank, applies only to the materialthe workmanship and fastening is the same in both cases; but, as experience has shewn, the durability of the one is two or three times longer than the other. If we assume the difference in cost of material to be 50 per cent., the cost of labour and fastenings will be equal to the cost of the oak, or 50 per cent. on the price of the fir; the duration of the oak will be from 2 to 3 times longer than the fir. The account will stand thus:For Fir Planking. Material .. 100 Labour and fastening.. 150

For Oak Planking.

:

250

150

Material
Labour and fastening.. 150

300

Assuming that fir will last half the time of oak, its cost for the same period will be 500; whilst oak would cost but 300, to say nothing of the loss that must ac

crue from loss of freight during the repairs. That the practice of planking steam-boats with fir should have prevailed so extensively, can only be accounted for upon the principle that present_advantage and saving is alone regarded.

I should be glad to see an end put to the practice of using fir for planking seagoing steamers: it is unfit for the purpose, both as it respects strength and durability; a great number of instances might be quoted in proof of this statement: instead of the present cheap method of running these vessels up, a more careful and scientific method of construction should be adopted.

It was my intention to have suggested some improvements upon the present method of construction; but, as I have for the present occupied too much of your space, I forbear.

I am, Sir, yours &c.

GEORGE BAYLEY.

1, Addington Place, Camberwell, May 22, 1838. P.S. There is a material which appears exceedingly well adapted to the framing of steam-vessels, and has not yet been imported for that purpose. I refer to Saul timber, immense supplies of which could be readily obtained from the East Indies. There is another species of timber from the island of Fernando Po, which also appears extremely well suited to the purpose, some cargoes of which have already been imported into England.

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THE IRON STEAM-BOAT RAINBOW" -SPEED OF THAMES STEAMERS.

Sir,-The good folks of Liverpool appear to be in a fair way to bear the palm of boasting from their hitherto successful rivals, the Americans; indeed I think upon the subject of the above-named vessel, they have beaten them hollow.

Fame has blown herself hoarse during the last fifteen months, trumpeting the praises of this wonderful vessel; when the keel was laid long since, various were the statements made by the friends of the builder and engineer, as to what her intended performance was to be; fifteen miles per hour was said to be the speed contracted for, and for every mile above this small speed, some thousands per mile were to be paid. She was to be constructed of iron, instead of wood, of the great length of 190 feet, and 180

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