Page:The Building News and Engineering Journal, Volume 22, 1872.djvu/282

 264 THE BUILDING NEWS. Marcu 29, 1872. in relation to our own country. M. de Frécinet says:—‘‘In England, the manufacturers, forming part of the Government, and not fearing auy censure, neglect to apply in their works the preventive systems adopted elsewhere.” Were this true, it would be one of the most serious statements that were ever made against a nation or a Government; but M. de Frécinet is able to find “‘some excep- tions,” and amongst these are Messrs. Rodgers, of Sheffield; Thomas, of Redditch; Price’s Patent Candle Company; Crossfield, of S. Helens; and Elkington. Any Englishman at all acquainted with the subject could multiply these so-called exceptions by a good number. The value of M. de Frécinet’s work lies, however, in his accounts of what has been done on the Con- tinent, and these deserve serious study. —_2——_——_ LAMPLIGHTING BY ELECTRICITY. PLAN for lighting street and other lamps by electricity has been “invented” by a resident of San Francisco. Dr. Van Zandt not only lights the gas, but also turns it on or off by electricity. The lamps are connected by underground wires with a central station, where the apparatus is situated, consisting of a galvanic battery, an induction coil, and a switch to throw the current on or off the wires in any portion of the city, so that all or any part of the lamps may be lighted or extinguished as required. Two independent circuits are necessary, one for operating an automatic apparatys in each lamp by which the, gas is turned on and off; the other for conveying the current which lights the gas. ‘The wire for the last circuit passes across the slit in the burner, where it is broken, so that the passage of the electric current produces a spark which ignites the gas. The wire near the burner cannot be insu- lated by caoutchouce or cloth, as these are destroyed by the heat; it is insulated by winding it around non-conducting trunnions on the burner. Above these insulators the wires are of German silver tipped with platinum. Trials of this apparatus, using thirty-seven burners and over a mile of wire, have been made in one of the towns of the States, with results that show that the invention is appli- cable to the purpose for which it is intended. ——>___—_ SOFTENING FROZEN GROUND FOR EXCAVATING. M® ANDREW DERROM, of Paterson, New 4 Jersey, has patented in America for this purpose. This invention has for its object to re- ‘duce the expense of digging the ground during the winter season for building or other purposes, and consists in the application of steam to frozen ground for the purpose stated. At present, with frozen ground, the digging in winter'is very expensive and difficult, and consequently the preparation for a com- mencement of building during the cold season is not generally undertaken on account of the greater ex- pense. The hands are, therefore, mostly idle in winter. All this will be, it is claimed, avoided, and a flourishing trade continued throughout the year by the introduction of an inexpensive system of softening the frozen ground. The inventor claims to have ascertained that a small jet of steam applied underground will take the frost out of a disproportionately large extent of earth. He practically utilises the discovery by applying steam, under pressure from a boiler or steam generator, which is conveyed under the earth in asuitable pipe. Asit is forced out of the pipe, it interpenetrates the particles of earth, is condensed parts with its latent heat, and is asserted to thaw an astonishing space of ground in proportion to the quantity of steam employed. rz o—- LEGAL INTELLIGENCE. Re THe Lunpy Granitr Company.—The Lords Justices on Saturday last overruled the decision of the Master of the Rolls by which Mr. Harvey Lewis was ordered to repay the fees received by him as a director of this company. ; Burpine Socrerres AnD THE Press.—The trustees of the Birkbeck Permanent Building Society, London, on Friday applied to Vice-Chancellor Wickens for an injunction restraining Messrs. Ward & Co., from publishing a book entitled “Building Societies and Borrowers,” in which reflections were made upon the stability of the Birkbeck. The Vice-Chancellor regretted the Birkbeck had been mentioned by name, but it was done without malice, If he granted the injunction he would be doing more against the liberty of the press than had ever been done in any decided case. He should, therefore, dis- miss the motion, but without costs. Civil Cngineering. ON THE NORTH LONDON RAILWAY (CITY BRANCH).* (Concluded from page 201.) HE minimum width of the City Branch of the North London Railway between parapets, is 36ft., and the level of the rails at Broad-street terminus is 26ft. above the street level. All the iron bridges were severely tested by the Govern- ment Inspector previous to the line being opened for public traffic, and in all cases the result was highly satisfactory. On the Kingsland-road bridge, for example, the span of which is 122ft., there were brought on to each line of rails three of the heaviest tank engines, each weighing 42 tons; there were, therefore, nine of these ponderous machines on the bridge at once, giving a total weight of 378 tons, the length of each engine from buffer to buffer being 384ft. Whether this enormous weight was sent across at full speed, or whether it was brought to a standstill on the bridge, the deflec- tion at the centre barely exceeded half an inch. The result was the same, in proportion to the span, with all the other bridges, and was a sufficient proof of the goodness of material and workmanship. All the wrought iron was rolled by the Butterley Iron Company, and Mr. Lawford tested it by putting it to a tensile strain of 20 tons to the square inch without producing any fracture. The rails used are of Bessemer steel, and were rolled at Cammell’s Works, Sheffield. They are double-headed, and weigh 82lb. per yard. The chairs are of cast iron, weighing 42lb. each. Since the line was opened— nearly 6} years ago—not a single rail has been renewed, and this, with five hundred trains running daily over the line, drawn by engines whose maxi- mum weight is 45 tons. There are four stations on the line—viz., Broad-street (terminal station), Shoreditch, Haggerston (which was not built till some time after the line was opened), and Dalston Junction (where the line diverges east and west). The works were commenced in April, 1863, and opened for public traffic on Ist Nov., 1865. The total cost of the stations and works, exclusive of the cost of permanent way materials, but including ballasting and laying rails, was £413,700, made up as follows: Viaduct, bridges, retaining walls, &c., £253,000 ; Broad-street Station (passenger), £120,000; Shoreditch Station, £9,500; Haggerston Station (including widening of viaduct from Acton- street to Dunston-street), £16,000; and Dalston Junction Station, £15,200. To this total of £413,700 were to be added the cost of the Broad- street goods station, £250,000; and the cost ofland, compensations, &c., £780,000 ; the cost of the rails, chairs, and sleepers, which cannot have been less than £15,000; and £100,000 for the widening out of the fourth line between Worship-street and Dalston Junction, making a grand total of £1,558,700, for a little more than 2} miles of rail- way—i.e., at the rate of £620,000 per mile. There are 820 yards lineal of cutting between retaining walls, 330 yards lineal of embankment between retaining walls, 3,620 yards of arching, 20 cast- iron bridges, and 17 wrought-iron bridges—the former varying in span from 20ft. to 32ft., and the latter from 32ft. to 122ft. The quantities of work and materials used in the construction of the viaduct and bridges were as follows: Exca- vation (one-third of which was ballast) 150,000 cubic yards (not including that from foundations) ; concrete, 39,000 cubic yards; brickwork in mortar, 137,500 cubie yards; stonework (dressed), 68,550 cubic feet; asphalte, 56,300 square yards; York flagging, 76,880 square feet; granite kerb, 12,600 lineal feet; road metalling, 15,850 square yards; drain-pipes (from Gin. to 12in.), 9,100 lineai yards ; wrought iron, 2,021 tons; cast iron, 2,420 tons; and lead, 18 tons. The contractors were Messrs, Waring Brothers, for whom the iron bridges were manufactured by Mr. James Haywood, jun.,of Derby. The superstructure of the Broad-street passenger station was built by Messrs. Cubitt, and the whole of the goods station by Mr. John Jay. Mr. W. Baker, of London and North Western Railway celebrity, was engineer-in-chief,Mr. Lawford (the author of this paper) being resident engineer. Mr. Stainsby was the architect of Broad-street Station, and Mr, J. Livock of Shoreditch and Dalston Stations. The Haggerston Station Mr. Lawford believed to be the joint production of three or four gentlemen. Mr. Lawford said that his best thanks were due to Mr. Pichlier for his valuable assistance in connection with the iron bridges, and to Mr. Wheat, who acted Engineer's Society, on Friday, March lst, by Mr. W. LAwrorp, M., Inst. C. E. as engineer for the contractors, for the great care, skill, and attention he bestowed on the setting-out and execution of the works throughout. Since the line was opened, a galvanised iron ceiling with gutters has been suspended to every one of the wrought-iron bridges, to catch the water leaking through the floor of the bridge. The retaining wall, a short length of which showed signs of weakness, is on that side now being widened out for the fourth line of rails, and semicircular arches have been turned against the work, so that it isnow impossible that any further subsidence can take place. The cost of the City Branch of the North London line compared favourably with that of other metro- politan and suburban lines. The Charing Cross Railway cost £1,000,000 per mile; City Branch of North London Railway, £620,000 per mile; Black- wall Railway, £432,000 per mile; North London Railway (main line) £180,000 per mile; West London Railway, £120,000 per mile; and the West London Extension Railway, £100,000 per mile; these figures including land and stations. The fol- lowing lines cost, exclusive of land, but inclusive of stations :—Metropolitan, £175,000 per mile; Metro- politan Extension, £180,000 per mile; Metropolitan District, 185,000 per mile. The roof of Broad-street Station (600ft.x200ft.) cost £30 per square; S. Pancras Station roof, £31 11s. per square; Charing Cross Station roof, £40 per square; Cannon-street Station roof, £50 per square. DISCUSSION. Mr. Artuur C. Paty, Assoc. Inst. C.E. (Presi- dent), regarded Mr. Lawford’s paper as a most valuable and instructive description of a very im- portant engineering work, and it was greatly to be wished that all the papers read before the society were as fully illustrated by plans and drawings as was the case in this instance. It was only to be regretted that the paper was not read at an earlier date, as a work that had been completed for six years necessarily lost some of the interest that would otherwise attach to it. He should like to know whether, if Mr. Lawford had his own choice in carrying out metropolitan lines, he would make them overhead or underground? He should imagine that, from a pecuniary point of view, the under- ground plan was the best, for although the engineer- ing of an underground line was doubtless more costly than that of an overhead line, still, as a rule, nearly all the land above an underground line was available for building and other purposes, whereas in an overhead line the only return available was by letting the arches for shops, warehouses, and stables. Another question he wished to ask was, whether on sharp curves of ten chains radius, where there was a liability of the walls beating out by the constant passage of the trains, it would not be better to lay the line on a system of wrought- iron girders stretching from side to side of the via- duct? It was well known that as cities got older the depth of soil increased, and he should like to know whether it was found that as the City was neared the depth of ‘‘made-ground” increased, and in what proportions ? As to thedripping of rain through the iron bridges, it had been sought to remedy that by roofing, or rather ceiling, the underside of the bridge with corrugated sheet iron; and though this remedied the immediate defect, it led to other incon- veniences—namely, increased liability of the iron- work of the bridge to rust, and increased difficulty in getting at such ironwork for re-painting, &e. If this corrugated iron plating was put too close to the ironwork of the bridge—and considerations of ‘headway ” often prevented any great interval be- tween them—it would necessarily tend to keep the latter damp, and of course increased corrosion would ensue—a thing greatly to be deprecated, especially in connection with wrought-iron bridges. As to the object of traffic managers in haying three rather than four lines of rail leading into a terminus, it was done for this reason: one down line was, in most cases, found to be sufficient, because all trains leaving the station could be sent away punctually at their proper times without interfering with one another ; but however punctually trains might be started, it was impossible to get them to arrive with equal punctuality, and therefore where there were two main up lines, or one main up line and one district up line, both running into the same station, the trains were able to run in without interfering with each other, even if unpunctual. With regard to the goods station at Broad-street, he should like to know more about its arrangement—whether it was on the ground level or on the level of the line, or both, and what arrangements were made for lowering and raising trucks and goods, and for providing sidiag room. All these were important questions for con- sideration in constructing a large goods station in the heart of a populous district, which often involved the stopping-up of existing thoroughfares.
 * Abstract of paper read before the Civil and Mechanical