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10 THE CIVIL ENGINEER AND ARCHITECT’S JOURNAL [Jan. 6, and to the corresponding front ribs; this double framework, being braced together with horizontal and diagonal tension rods of iron, is planked on both sides, and made perfectly water-tight. The gates constructed in this manner are extremely light and buoyant; and by the admission of more or less water, with additional balance weights, the buoyancy of the gate is so adjusted that its whole weight is borne by the water, and, consequently, very little power required for opening and shutting, besides the great saving in tear and wear thus reduced to a minimum ; in proof of which it was stated, that instead of from ten to twelve minutes, with four men, the time and power usually required for opening or shutting gates of similar dimensions, these gates, by means of improved crab gearing, are opened or shut in three and a half minutes, with only two men; and with a longer allowance of time, even one man is able to work them. Thanks voted, and given from the chair. 2. u Observations upon Iron Lattice Bridges.” By the same. Mr. Thomson illustrated his observations - with numerous drawings and models of several lattice bridges already completed, or at present carrying into execution, by Mr. Macneill and himself. The principle of lattice bridges, applied in timber, has for some time back been in use in Ame« rica; but the adaptation of the principle to iron bridges, as now so success fully applied by Mr. Macneil and Mr. Thomson, is likely to supersede, in a great degree, the use of timber, and will supply a desideratum hitherto felt in establishing internal lines of communication, &c., where the expense of stone bridges not unfrequently precludes their being carried into effect, while the objection to wooden structures on the score of durability is obviated by the substitution of iron. The first bridge of this kind, recently completed by Mr. Macneil on the line of the Dublin and Drogheda Railway, and of which drawings were exhibited, is 85 ft. in span, consisting of two lattice-work frames or beams, one on each side, resting upon stone abutments ; the lattice- work beams are composed of small bars of malleable iron, about 12 ft. long, and only a quarter of an inch thick, placed so as to cross each other at right angles, and forming a net or lattice-work, rivetted at every intersection; the lattice frames, so constructed, and stiffened with angle iron, support the roadway hv means of light transverse beams, also of malleable iron, secured to the lattice-work at each end. This bridge, which altogether weighs only fourteen tons, sustained a load across its centre of twenty-four tons, under which the deflection amounted only to 3-10ths of an inch. A viaduct 230 ft. in length, with a central span of 140 ft., is now being constructed by Mr. Macneil, over the Royal Canal in Ireland, for heavy locomotive traffic. This viaduct, of which Mr. Thomson exhibited drawings, has a third lattice-frame in the centre, and is composed of malleable iron bars half an inch thick. Mr. Thomson described a very useful application of this principle to the widening of the roadways of existing bridges: and exhibited a pretty constructed model of one of the arches of a stone bridge, about 400 ft. long, with the addition of footpaths on each side, as at present executing under his direction, the old width of roadway being only seventeen feet, while, with the new footpaths, supported by iron lattice-work, the width will be increased to thirty feet. The appearance of these bridges, which may be either perfectly straight or s-lightly curved, as circumstances require, is light and graceful, combining as they do great strength with the least possible quantity of materials, and seem to be admirably adapted for crossing wide and deep valleys, rivers, &c. at a small expense, as also for ornamental bridges in parks, or approaches to gentlemen’s seats, &c. The expense of construction, Mr. Thomson estimates at less than half the cost of stone; but be stated that he was at present making an investigation into their principle, with experiments upon a different arrangement of the lattice-bars, which he hoped would lead to a considerable saving both in the quantity of material and workmanship. NOTES OF THE M'EEK. The sculptural decoration of the metropolis seems to be a great attraction just now. The statue of Nelson has been elevated to the top of the pole in Trafalgar Square, where it has produced such an effect, although a merito- lious work of art, that we question whether anymore monostvlar monu ments, supporting nothing, will be erected for some time. We must say that the present is a luckless specimen; we have heard of midshipmen being mastheaded, but we never saw an admiral mastheaded before. It seems that discontent and disgust have even afflicted the committee ; they are going to have the cable at the feet of the Admiral altered, so as to give greater so lidity to tiie statue. We wish while the statue is up, that they would knock < ff the cocked hat, which is too great an attraction, catching the eye from every point. The statue of George IV., by Chantrey, is also mounted on the pedestal near St. Martin’s Church. It seems, on a cursory view, to be a good likeness of the King, and the horse, which is a powerful charger, planted on his four feet, with his head slightly turned, is a fine one. We must, how ever, see more of it. George III. is, it seems, to come from Pall Mall to the North West pedestal opposite the College of Musicians. We hope the pigtail of this statue will also be cut off. The statue of William IV., by Nixon, is nearly ready. It is to be placed at the junctions of King William-street and Gracechurch-street. We hope the artist has not, agreeably to the practice of modern art, represented the Sailor-King with a doodeen in his mouth, or some other attribute of the ruling habit of the living man ; the statue, of Devon granite, is fourteen feet high, and cost £2,200, voted by the Corpora tion of London. What inconvenience would it be to the Corporation of London to vote a similar sum every year, for a statue of some man of genius born in London, and who has a right to such honours at the hands of its municipal authorities. We can give some names to keep them going for a few years, and tell them where to put them. Milton, Bread-street, Cheap- side ; Pope, Lombard-street; De Foe, Cripplegate, (or Finsbury Pavement). Mr. Nixon has finished the series of the Four Seasons for Goldsmiths’ Ilall. The last statue is that of Autumn. He has in hand a statue of Mr. Carpenter, the founder of the City of London school, to be placed in the vestibule of the school; and also of Sir John Crosby, for Crosby Hall. It has been noticed, as in some degree singular, that statues are now being erected to two con temporaries and near neighbours—Whittington and John Carpenter. Mr. Bailey, R.A., has in hand a marble statue of that excellent statesman, Sir Charles Metcalfe, to be 9 ft high, and cost £3,000, to be placed opposite the Senate House, Kingston, Jamaica. A bust is also to be sent to Calcutta, lie is also occupied with the statue of Sir Astley Cooper, for St. Paul’s, which will soon be placed on its pedestal. Some noise is being made about cheap imitations of bronzes in zinc, but we have not seen any of them. As an example of the increased attention paid to decorations, we are glad to instance the three new doors just completed for York Minster, from the designs of Sydney Smirke. The three doors are alike of the decorated style, 1G ft. high, and 6^ ft. broad. The tracery in the upper part is very rich, sup ported by slender Gothic columns. The hood mouldings spring from the tops of the capitals, and terminate in rich finials and crocketting. Three trefoils, bearing shields, occupy the centre of the arches, and the lower part of the door is divided into six decorated compartments. The work is exe cuted by Mr. Wallace and Mr. Scott, of Newcastle. Mr. Rigby has taken the contract for the erection of the new Marine Bar racks at Woolwich, for £70,000. The works have been commenced. The barracks are to accommodate a thousand men. The Woods and Forests have begun pulling down the Rookery and neigh bourhood, to make way for the new road from Buckingham Palace to the Vauxhall Road. The embankment of the Thames is also to be proceeded with. The Glasgow and Ship Bank, at Glasgow, has been completed. Six em blematical statues, by Mr. Mossman, jun., occupy the pedestal. They are, Britannia, the City of Glasgow, Wealth, Justice, Peace and Industry; each seven feet high. Hess, of Munich, the painter, has finished his grand painting of the Battle of the Borodino, or the Moskowa, for the Emperor Nicholas. It is looked upon as something grand in the great way. The splendid gallery of Cardinal Ilesch is at last to be sold, at Rome, and is the object of much attraction, from the value and intrinsic merit of the collection. It contains good specimens of nearly every school. St. Stephen’s, Coleman-street, has got a new altar window', of painted glass. It is well executed, but the subject is ill chosen, being Ruben’s De scent from the Cross. All imitations of historical pictures are bad. Barbarism is not, as some have surmised, a pure English quality. Even German artists go the length of destroying rival works, by stillettoing fres cos in public places. A triumphal arch is to be erected in the Ludwig Strasse, at Munich, by Von Gartner, the sculpture to be by Wagner. The Commune of Hornu, near Brussels, intends to erect a church, the interior of which, it is said, will be entirely of iron. It is announced that the British and Foreign Institute has now r reached to nearly 1000 members. The Institute will, therefore, be opened on the 15th instant; the lectures and the soirees on the assembling of parliament. The literary department is to be under the direction of Mr. Buckingham; and besides the attractions of the reading-room and library, with the public journals of various countries, there will be engravings, pictures, and works of art and vertu, to be collected for the inspection of visitors, it is also intended to introduce occasional music, vocal and instrumental. It is determined also to divest these entertainments, as much as possible, of the formality of a public occasion, and make them resemble, in every particular, an evening party, conducted with all the ease of a private assemblage in the best cir cles. The hotel department, for which a separate mansion has been taken, will be under the direction of Mr. Whitmarsh. Patent Bearings tor Locomotives.—At the Liverpool Polytechnic So ciety, Mr. Dewrance (superintendent of the engine building department of the Liverpool and Manchester Railway) exhibited some very perfectly cast and beautiful specimens of the “ Patent. Metallic Bearings, or Steps, for Locomo tives,which had been found to be superior in practice to those previously used, and which, the metal being soft, considerably diminished the friction, by working more smoothly, while, at the same time, they lasted much longer than was anticipated. One engine had run with them a distance of 4,480 miles without requiring renewal or repair, and another (the identical bearings of which were produced) had run 1,000 miles, without additional giving or vibration. The substances for the part in which the axles worked, which he had combined in one instance, and found to be effective, were, six parts of tin, eight of antimony, and four of copper, forming (as we understood him) a solder. Mr. Dewrance also pointed out various plans of giving an equal supply of oil.
