32

NOTES AND NOTICES.

It is said that the Marquis of Westminster contemplates the construction of a magnificent suspension bridge over the Thames to the Red House, Battersea.

Prize Chronometers.-Government having determined on discontinuing the prizes for chronometers, which shall have performed within certain limits during a twelvemonth's trial, at the Royal Observatory, Greenwich, the last public trial terminated on the 1st inst., when Mr. John Carter, of 207, Tooley-street, was again declared (as last year) alone entitled to any reward; his chronometer, No. 160, being the only instrument remaining on trial since January 1836, although, at the commencement, in March, 1835, sixty-four chronometers were placed in competition, but, exceeding the prescribed limits, were returned to their respective makers. It certainly reflects great credit upon Mr. Carter, when we aanounce this as the fourth year his chronometers have, by their uniform and steady rate, under great variation of temperature, been found deserving that high and proud distinction which the Lords Commissioners of the Admiralty have been pleased to confer. The extreme error, for twelve months, of Mr. Carter's chronometer, No. 169, was one second, 47 hundredths.-Daily paper.

New Discovery in the Process of Casting Iron Dr. Charles Schaff hautl, a German at Sheffield, has lately discovered that by producing an evaporation of the chlorine in making cast-iron of the second and third quality, an iron of the first quality is produced. A patent has been taken out for the discovery, of which Messrs. Hollis, Solly, and Son, of the Tividale Iron-works, are proprietors.

Ballooning.-Dr. Agme in a recent essay, which he read at the French Institute, endeavours to prove that it is possible to obtain such a hold on the upper atmosphere as to be able to direct a balloon with all the steadiness and certainty of a boat moving in the waters. This he proposes to accomplish by means of oars or levers to be attached to the car, and which are to be made of oiled skin, or cloth, capable of containing an adequate quantity of hy drogen-gas, the specific gravity of which being lighter than the air would obtain a hold on the natural fluid, as they would meet with the same resistance as the balloon does itself.-Globe.

Cultivation of the Vine in England.-I planted a small vineyard for an amateur, which the third year produced so abundantly as to enable him to send large quantities of fruit to his friends, and also to make a hogshead of wine for summer drink-the sorts, Burgundy and sweet water. The best method in establishing a vineyard on a small scale is this: To plant out vines raised from buds, or cuttings, or layers (say of one year's growth), let them be put out in rows, eight feet apart by six feet from plant to plant in the rows; if the shoot is strong and well ripened, head them down at once to within two feet of the ground; when they break, let the two top buds each form a shoot, which is to be trained parallel to the ground at that height, and fasten cach to an upright stake. At Midsummer shorten back each shoot to about two feet, or, if strong and plenty of fruit, three feet. The following year four, five, or six buds may be left, according to the st ength of the plant, each to form a fruiting bongh, and trained as before. These radiating equally from the centre, will be the maximum number allowed. Every winter pruning season éach shoot is to be cut back to one well-formed bud of the preceding summer's growth, which bud is to produce the succeeding summer's fruit. In the summer pruning each fruiting bough is to be shortened back to the length before stated, allowing three or more bunches of grapes to ripen upon each. These banches, when the fruit is stoned, should be -well thinned ont (say half left) to allow the berries to grow to a large size and colour equally, which

add to their weight, beauty, and flavour. If the soil is a cold stiff clay, it can be prepared by trenching it two spades deep, and burning it with faggots. If a thin soil, or a chalk subsoil, then it ought to be prepared with good loam, or rich alluvial soil, at least a foot deep. If a wet bottom, it should be drained. Plants treated in this manner will last many years; to vary the vineyard, a few plants might be trained upright to a pole, or in graceful festoons (one shoot only), which should never be headed back lower than the height you wish it to grow, the lateral shoots should be shortened back to the main stem every year, leaving only one bud as before directed; and last, in thinning over the leaves, it should be remembered that their functions are important, and necessary to the perfect elaboration of the sap, and consequently the perfection of the fruit. The hardiest sorts for our climate are the black Hambro', Burgundy, cluster, white, 'sweet water, and royal murcadine; but the curious amateur may perfect tenderer varieties by the aid of temporary glass, placed close over the branches in a proper position to catch the sun's rays.-Sunday

Times.

Double-acting Gasometers-Another Claimant.Sir, I beg to inform you the Messrs. I. and T. Waites, of Diss, have invented and constructed (without previous knowledge that, there was such a thing in the world,) a double-lifting gasometer-it has been made about one year, and is in constant use and answers remarkably well. A model of it may be seen in their shop.-I remain, your obedient servant, J. M. BECKLEY. Wortham, near Diss. March 14, 1836.

Baron de Férussac.-We are sorry to announce the death of the indefatigable Baron de Férussae, the founder and editor of the Bulletin Universel. He had long suffered from an affection of the lungs, but did not quit his labours till just before his death. Among other excellent works, his Natural History of Mollusca was one of the first, and is illustrated by the best plates published in France; his monograph on Cephalopoda is equally beautiful, but neither of these undertakings is finished. He was always anxious to forward the views of those connected with science, and was particularly obliging to foreigners. He was in his fifty-second year. Athenæum.

Errata. In Iver Maciver's article in our last Nunber, p. 14, col. 1, fine 4, for "rising 1 in a foot" read" rising 1 in a feet;" lines 5 and 6, for "the resistance has been found to be th part" read "the resistance on a level has been found to be In col. 2, line 8 from bottom, for "19" b. read " 19. Also in Mech. Mag., No, 655, p. 434, col. 1, line 20 from top, for "240= b" read "200=b."

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. Drawings of Machinery also executed by skilful assistants, on the shortest notice.

LONDON: Published by J. CUNNINGHAM, at the Mechanics' Magazine Oflice, No. 6, Peterbo rough-court, between 135 and 136, Fleet-street. Agent for the American Edition. Mr. O. RICH, 12, Red Lion-square. Sold by G. W. M. REYNOLDS, Proprietor of the French, English, and American Library, 55, Rue Neuve, Saint Angustin, Paris.

CUNNINGHAM and SALMON, Printers,
Fleet-street.

34

MACKINTOSH'S IMPROVED PADDLE

WHEEL.

Sir,-At a time like the present, when steam navigation is rapidly extending itself throughout the whole British dominions, whatever tends to its improvement must be deemed a matter of national importance. Under this impression, the inclosed sketch of an improved paddlewheel is submitted for your consideration, that it may be inserted in the pages of your useful Magazine, if, in your judgment, it shall appear to merit such distinction. I have taken the excentric motion from the outside of the paddlewheel down to a cross-shaft, which moves on its centre, and is placed at a short distance above the paddle-board; from this cross-shaft two rods (instead of one, as in Morgan's) extend to the paddle-board. It is not pretended that this wheel is original-the principle is the same as Morgan's; but by this arrangement the shaft (the principal point of strength in the framing) is allowed to pass entirely through thus all the advantages of the epicycloidal motion of the paddles is retained, whilst the strength of the wheel remains unimpaired. The principle of Morgan's wheel is excellent; but until that can be fitted with a shaft entirely through the centre, it cannot be trusted or deemed seaworthy by any experienced engineer, however strongly it may be supported by written testimonials.

Although steam-navigation is of comparatively recent introduction, no less than fifty or sixty patents have been granted for improvements in paddlewheels. This at least shows the importance that is attached to this part of the machinery; but in almost every instance it has, unfortunately, happened, that a great deal has been sacrificed to attain one particular object. It may, therefore, be worth while to inquire what are the essential qualifications of a good paddlewheel. It seems to be allowed on all hands, that that wheel which most perfectly fulfils the three following conditions is the best:

1st. That gives the most effective stroke, or greatest amount of propelling power.

2d. That most effectually clears itself of the back-water, and thereby causes the smallest amount of swell astern of the vessel,

3. That is simple in its construction, durable, and not liable to derangement.

There has no paddle-wheel yet been offered to the public which completely satisfies these conditions, although it must be allowed that some have approached much nearer than others to this ideal perfection. Nearly all these fifty or sixty patent wheels are laid aside, or cushioned, as they say in the House of Commons; however, there are a few of the more recent in the construction of which considerable ingenuity is displayed, and which appear, in some respects, well calculated to obviate the evils that have been complained of in the common wheel, and upon these I will venture to offer a few observations-taking them in the order in which they have appeared in the Mechanics' Magazine.

Morgan's wheel has been already noticed; it appears to give a most effective stroke, to clear itself of the back-water admirably-but is wofully deficient in strength and durability, and therefore until this defect is remedied, cannot come into general use.

Symington's wheel appears to give a less effective stroke than Morgan's, but is well calculated to destroy the swell in the wake of the vessel, because as the two floats of which the paddle is composed cause the back-water to recede in opposite directions, the one portion acts as a check upon the other; and thus the effect is neutralised, and the evil consequences arising from the undulations obviated. These wheels are, therefore, well adapted for river work; and were they in more general use, might be the means of preventing a great and unnecessary loss of human life. But the manner of working the floats, or causing them to revolve, is decidedly bad. The friction upon a roller working in a groove is very great when the angle is sufficiently acute to give the proper direction to the paddles, and must, therefore, cause a considerable loss of power, and also occasion the working parts to wear out very rapidly.

Seaward's wheel is (whatever the ViceChancellor may say) nothing more or less than a modification of Morgan's; the construction is the same in every particular, except as it is expressed in the affidavit of Messrs. Morgan and Lucena, the excentric is caused to "revolve on an enlarged axis affixed to the side of the

said steam-boat," It is not here intended to insinuate that Seaward's wheel is an infringement upon Morgan's or Galloway's patent; on the contrary, it is notorious to every one at all acquainted with the subject, that the principle of causing the floats of a paddle-wheel to revolve by means of an excentric was well known and acted upon many years before either Messrs. Galloway, Morgan, or Seaward, attempted, or possibly even thought of attempting, to accomplish that object by the same means. All that is meant to be bere asserted is, that Morgan's wheel and Seaward's are the same in their mechanical construction, except that in Seaward's the main shaft passes through the wheel, and the excentric works upon an

enlarged axis." In point of strength and durability, when compared with Morgan's, Seaward's wheel has decidedly the advantage. But as regards the excentric action, the friction of the working parts, especially upon the "enlarged axis," is so very excessive, and presents so great a drawback on the working of the wheel, that it is very questionable whether it possesses any superiority, or whether it is, in all respects, even equal to the common paddle-wheel.

Carter's wheel is, in principle, a combination of Morgan's and Symington's; there is much ingenuity displayed in its construction, but it is too complicated. It bears evident marks of being the production of an amateur engineer, and may suit very well his amusement or recreation, but appears ill-adapted for the purposes of navigation.

And last and least, Galloway's second patent. This wheel has been strongly recommended by the inventor on account of its simplicity and power; and how is this power obtained? The inventor says, in his circular, that of the series of bars of which his paddle is composed, "the lowest bar only encounters a resistance at entering, the other bars following in its wake or path." If this were really the case, a very considerable portion of the power must be lost altogether, as it is by the resistance which the water opposes to the revolving of the paddle-wheel that the vessel is propelled, and, consequently, an increase of speed cannot be obtained under such circumstances. This wheel is calculated, however, to obviate one evil -the tremulous motion or vibration communicated to the vessel by the successive

striking of the paddle-boards as they enter the water; but this object might be equally attained by fixing the bars composing the paddles at regular intervals upon the outer rim of the wheel, or by placing them upen steps, as in the patent wheel-in either case, it is simply dividing the heavy and perceptible stroke of one great paddle-board into several lesser, which are not so perceptibly felt. The merit of this wheel certainly lies in its simplicity; and perhaps the inventor himself may be allowed to possess equal merit of the same description.

Sir, I have animadverted freely on the several paddle-wheels now before the public, as I conceive I had a right, and was perhaps, in some measure, in duty bound to do; and shall conclude with this observation, that I freely concede the same right to any gentleman who may feel disposed to criticise this which is now submitted to the public.

I remain, Sir, yours respectfully, Thos. S. MACKINTOSH. 101, Long-alley, Finsbury, Feb. 25, 1836.

Description of the Engravings.

Fig. 1, represents my paddle-wheel with stay-braces or outside bearing; and fig. 2, a paddle-wheel without the outside bearing; the former of these arrangements I consider the best.

In fig. 1, aa is the wheel; bb, staybraces, fixed firmly into the brass collar c, which collar works freely on the pin g; d, excentric motion; ee, cross-shafts ; ff, paddle-boards; and g, pin to support the outside of the wheel by means of the stay-braces bb.

MERRYWEATHER'S FIRE-ENGINE BRANCH

PIPE.

Sir, Many circumstances have prevented me from resuming the consideration of certain hydraulic phenomena that were under discussion in your last volume, until a comparatively recent period, when I had an opportunity of repeating the experiment which gave rise to the question, and also of making some other experiments, alluded to in my communication at page 227; the results of which, but for a severe domestic affliction, should ere this have been laid before your readers.

On making another trial of the flattopped branch-pipe, described at page 6 of your 23rd volume, I found I had committed the error attributed to me by J. L.,