of the engines, when loaded, is 74 miles an hour on the ascending grades, and from 5 to 6 miles an hour on the descent. Greater speed and larger loads might doubtless be permitted with success ; but the policy has been to work the track with perfect safety, to risk nothing, and to obtain and hold the public confidence.—Mechanics' Magazine, No. 1753.

NOVEL RAILWAY SYSTEM.

MR. J. B. HUMPHREYS, C.E., of Rio de Janeiro, has patented a novel arrangement of the parts of Railway Trains intended for conveying goods and passengers up steep gradients, where the present system of traction by locomotive engine power is difficult and expensive, or entirely inapplicable. Instead of one or more locomotive engines of great power and weight, trucks in a series are each fitted with steam-engine cylinders, by the action of the steam in which motion is communicated to the wheels of such trucks or carriages; and the steam necessary for communicating the power may be conveyed from the boiler of a locomotive traction engine in the front of the train, to the trucks composing the train by means of suitable steam pipes; or a separate boiler is mounted upon each of several suitable trucks, disposed in consecutive positions throughout the length of the train, according to the number of steam trucks composing such train.-Mechanics' Magazine, No. 1753.

ASCENT OF STEEP GRADIENTS ON RAILWAYS.

MR. GRASSI, of Milan, has patented an application of the Archimedean Screw to Locomotive Engines, for taking trains up Steep Ascents on Railways. Captain Moorsom, C.E. (who himself invented a system, and introduced it in 1840, at the Lickey incline), has examined Grassi's system by the model, and is of opinion that the screw may be worked as the patentee states. Captain Moorsom further states the method by which he would proceed to apply Grassi's invention.

He proposes to construct a locomotive engine with 18 inch outside cylinders, 4 feet driving wheel and 24 inches stroke, with boiler capacity sufficient to provide steam (with proper expansion gear), for a speed of not less than 12 miles per hour on the incline; with a gross load of not less than 100 tons, including the weight of the engine and tender, which would probably amount to about 28 tons. The engine will carry her tender upon her own frame. On the driving axle of the engine a bevelled wheel will be fixed, so as to connect by means of one intermediate motion with the crown wheel on the end of the shaft of the screw.

The driving wheel and screw revolve in exact ratio to each other, so that the screw will advance exactly as the driving wheels advance ; or, in other words, each revolution of the driving wheel sends the screw forward nearly 12 feet 7 inches. Thus 12 turns of the screw are made for every turn of the driver. Captain Moorsom believes about 13,000 such revolutions of the wheel would be made per hour on the level, and that if the same motive power be applied to turn

D

the screw on the incline above stated, of one in twenty, the steampower will overcome the additional resistance arising from gravity and the friction of the machinery, at a speed not less than from onethird to one-half of that attained on the level with the same load.

With respect to the screw in its relations to the road, Captain Moorsom proposes to make the thread of the screw to be of 13 inches diameter, winding round a cylinder or shaft of 7 inches diameter, and with a pitch of 12 inches. The cylinder screwed will be about 5 feet 4 inches long, and will always hold two of the rollers in its grasp at one time.

The rollers or pulleys will be placed 3 feet 2 inches apart from centre to centre; they will be about 8 inches in diameter, will revolve into a longitudinal balk of timber, and will be lubricated in the same way as the wheels of the carriages.

The bearing timbers for the rollers will be a single line of balks about 10 inches wide by 8 inches deep; thus each mile will require 2933 cubic feet of timber and 1668 rollers.

The rails will be bridge rails, weighing 65 lbs. per yard, and screwed to balks equal to a section of 10 inches by 8 at the least. This road will be necessary to be thus laid only on the up side of the incline, and is a not unusual mode of constructing the permanent way. The cost, 37017. per mile. Cost of the engine, with tender and screw and connecting gear complete, 30007.

The rails are not additionally expensive on account of this peculiar construction. Thus we may say that in England the total cost of one mile of railway prepared for this mode of traction will be about 37007. additional as compared with the expense of construction of an ordinary mile of the same railway line; and the additional cost of the engine over and above an ordinary assistant, or bank engine, will be about 5001.

The result will be that such ordinary bank engine, if constructed and worked as is usual on the best European railways on steep inclines, would take about 50 tons of load up one in twenty; whereas this engine, constructed as above described, would take about 80 tons of load up the same incline, and no doubt a more powerful engine would take a greater load.

The maintenance of exact action between the wheel and the screw -the friction of the rollers-the economy of the maintenance both of the engine and of the road-are three points of difficulty about which various opinions will prevail, till the system has had the test of practice. Captain Moorsom's opinion is, that these difficulties are only such as the skill and economical care of an engineer, well used to working inclines, may successfully surmount.

The comparison between the estimated cost of a railway over the Alps or the Pyrenees, after the Grassi system, and the estimates of the most moderate projects with tunnels, &c., gives an enormous difference. Thus, the tunnel projected to cross Mont-Cenis, on the line from Lyon to Turin, is estimated to cost more than 100 million francs, even although there occurs a gradient of 2 per cent.; whilst on this same line, Mont-Cenis may easily be surmounted by the aid

of the Grassi system, at a probable expenditure of three or four million francs at most above the cost on ordinary railways, assuming that the increased length of the line is threefold that of the tunnel.

A pamphlet illustrative of the system may be had at the office, 14, Southampton-street, Strand.

SAFETY ON RAILWAYS.

PROFESSOR RANKINE, President of the Institution of Engineers in Scotland, observes that a class of legislation to which an institution of engineers should turn their attention is, laws concerning the public safety-laws to regulate the strength of boilers and the speed of railway trains. There are no laws enacted in reference to either of these matters; but if such laws were provided, they should not be calculated to check enterprise, or restrict or inconvenience inventors or manufacturers more than is necessary; and in order that the Legislature might be accurately informed of the circumstances that should guide them on subjects of the kind, it is of the utmost importance that these subjects should be publicly discussed at meetings by practical and scientific men. He was sorry to perceive a disposition on the part of some very eminent persons to recommend restrictions that he should think very injurious. For instance, Lord Brougham recently suggested that the speed of trains should be limited to twenty-five or thirty miles an hour! Now, under proper management, and with care, a speed of seventy miles an hour could be made with as much safety as seventeen, for accidents seldom occurred but through mismanagement; and the proper course to adopt would be to enforce proper management and caution. We hope this correction of Lord Brougham's suggestion may be as widely circulated as the error.

SUSPENSION RAILWAY BRIDGES.

MR. C. VIGNOLES has communicated to the British Association a paper "On the Adaptation of Suspension Bridges to sustain the Passage of Railway Trains." The subject was comprised under the following heads:-First, the maximum load to pass the bridge; second, the velocity of the train; third, the strength of the chains; fourth, the rigidity of the platform; fifth, prevention of undulation, vibration, and oscillation. The novelty of the author's inquiry in the matters he adduced was confined to the question of the rigidity of the platform. He instanced the bridge over the river Dnieper, at Keiff, in Prussia, erected according to his designs, and stated that the successful resistance of the well-braced platform of this bridge to the effect of hurricane winds had been long remarkable. This bridge was completed about four years ago, just before the commencement of the Russian war, and at a time when he little thought the result of his exertions would so soon be used in facilitating the military operations of the Russians against the allied forces. He alluded to the severe tests which it had successfully withstood, in the convey

At the Meeting of the National Association for the Promotion of Social Science, held at Birmingham, in October, 1857.

ance of armies with heavy ordnance; and he came to the conclusion that the adaptation of suspension bridges to railway purposes is quite practicable; recommending, at the same time, that the speed of the trains, when passing, should be kept moderate, as compared with ordinary speed on railways.

IMPROVEMENT OF PERMANENT WAY ON RAILWAYS.

MR. J. M. PARSONS, C.E., has succeeded in accomplishing a matter much wanted in the Permanent Way of Railways,-that of securing the ends of the rails firmly in their position, and thus preserving an even road at the joints of the rails. This is performed by means of his "wedge fish-joint chair," which is twice the length of the ordinary chair, and so contrived on one side as to catch the lower flange of the rail, and press close under the upper flange. The state of the rails near the joints secured by Mr. Parsons's method forms a striking contrast to those fastened in the ordinary way. is stated that the expense of removing the ordinary chairs, and replacing them by the "wedge fish-joint chair," will be comparatively small, being less than that of the cost of fishing, and capable of being more readily executed.

WROUGHT IRON RAILWAY CARRIAGES.

It

IN the Scientific American is described, in Patterson, N. J., a Railway Carriage constructed almost entirely of Wrought Iron. This material is employed to obtain great strength, with less weight than usual, and to avoid the serious injuries which generally occur to passengers in collisions with carriages of the ordinary construction. The framework of this wrought iron carriage is in effect an extremely strong and stiff, yet elastic, basket, each joint or intersection being strengthened by rivets, and the whole being further protected by making the entire platform at each end one strong spring of steel. Should this carriage come into collision with another in such manner that the springs at the ends cannot absorb the shock, the carriage will itself spring, collapse, twist, or crumple up, but cannot break and crush its contents with the fragments. One of the great dangers from collisions, &c., is the disposition of ordinary carriages to penetrate each other with their timbers, but this and many other minor evils are avoided in the improved carriage.

COAL-BURNING LOCOMOTIVES.

AN invention of the greatest importance to railway companies generally has for some time past been successfully employed upon the London and South-Western railway, by which, calculating upon seventy engines being in steam daily, a saving of 25,000l. per annum will be effected. The honour of the invention is due to Mr. Joseph Beattie, the locomotive superintendent of the line. Mr. Benjamin Fothergill, of Manchester, has severely tested the contrivance, and the average result obtained showed a difference in fuel of 4.01 lbs. in weight per mile in favour of the coal engine. Mr. Fothergill considers, however, that these results are partly produced by

Mr. Beattie's patented arrangement for heating the feed water before it is pumped into the boiler. Mr. Fothergill further states that the coal engines are fully capable of burning their own smoke; that they rapidly generate an abundance of steam; and that the burning of coal, according to Mr. Beattie's plan, is far more advantageous, as regards the durability of the fire-box and tubes, than coke could possibly be.

FENTON'S PATENT RAILWAY SIGNAL DETECTOR.

MR. FENTON, of the Low Moor Iron-works, has invented and brought into use an apparatus worked in conjunction with Railway Signals, and designed to act as a Detector,-by proving, in the event of an accident occurring, whether the warning signal was or was not set at the time of the passing of the train, and thus fixing the blame with certainty upon the culpable party-the engine-driver or the signal-man, as the case may be. The invention consists in placing a supplementary signal or semaphore between the station signal and the distance signal, or beyond the latter, or beyond both. The supplementary signal is worked in connexion with, and by the same handle as, either the station or the distance signal, and is used for indicating whether the one or other of these signals was set at the time the engine passed it. It stands only as high as the buffer beam of the engine, and is placed near the rails, so that when an arm is thrown out therefrom to danger, the engine cannot pass without breaking it down. The arm is secured in a socket, and may be readily replaced when broken, at a small cost; or the arm may be pointed in such manner that, instead of being broken, a portion of it may be turned out of its transverse position, and thus indicate the passage of the engine. The signal post will be inexpensive, as no lamp is required, and a short wire attached to that of the station or distance signal will work the supplementary arm. The additional signal post, when situated between the station and the distance signals, should be placed as far inside the latter as to allow an ordinary train to be protected by the distance signal when the train is pulled up short of the station. A thin glass phial, containing a coloured fluid (or other similar contrivance), may, if found necessary, be introduced into the end of the supplementary semaphore. This would be broken when the engine struck it, and the fluid be spattered over the buffer beam, more certainly insuring the detection of the culpable engine-driver. When the signals are set at caution, it is necessary that the supplementary signal post and arm should be so arranged that the engine and train will pass clear of them.-Mechanics' Magazine, No. 1762.

NEW RAILWAY SIGNAL.

DR. GRAY has described to the British Association a new Railway Signal, which has been tested very satisfactorily upon the Midland Great Western Railway. The qualities which it possesses, and which are relied on as establishing its value and efficiency, are―