1848.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



83 



BLACKWALL RAILWAY MACHINERY. 



Description of the Machinery erected by Messrs. Maudslay, Sons, 

 and Field, at the Minories Station, for um-king the London and B/ack- 

 viall Railway. By Andkew John Roblrtson.— (Read at tlie 

 Institution of Civil Engineers). 



The London and Blackvvall Railway is about 3f miles in length, 

 and is worked by stationary engines of the estimated force of 

 448 H. P. and 280 H. P.,* at the London and Blackwall termini re- 

 spectively : the carriages being attached by grips to a rope, which 

 is wound' oif and on to large drums situated at each extremity of 

 the line. The greater power is required at the London station, in 

 consequence of tliere being a total rise in the railway, in this direc- 

 tion, of between 60 and TO feet (average 68 feet) ; the steepest in- 

 dination being 1 in 100. There are seven intermediate stations on 

 this line; the Poplar, West India Docks, Limehouse, Stepney, 

 and Shadwell stations, communicate witli the Fenchurch-street 

 terminus ; whilst those of the Minories, Cannon-street, Shadwell, 

 and Stepney, communicate with the Blackwall terminus. This 

 arrangement is effected by appropriating a separate carriage from 

 the termini for each intermediate station, communicating with the 

 same; these are detached whilst the trains are moving, and by 

 means of breaks they are stopped at their respective destinations ; 

 as soon, however, as the terminal train arrives at either end of the 

 line, and the rope ceases its motion, these intermediate carriages 

 are attached to the rope, whilst it is in a state of rest ; so that 

 wlien the engines are again started, the carriages are also simul- 

 taneously set in motion, and arrive successively at the termini, in 

 the order and at intervals corresponding with the position of the 

 places from whicli they started ; as they arrive tliey are released 

 from the rope, though in motion, by the sudden withdrawal of the 

 grip iron, and then their momentum carries them forward to their 

 proper places in the station. It will be percei\ed, that the inter- 

 mediate traffic is by this means provided for, without causing any 

 detention to the through trade. 



The peculiar mode of working the line, nnd the circumstance of 

 so many carriages being attached to the rope at different places, 

 rendered it absolutely necessary to provide some quick and certain 

 system of signals between the termini and the intermediate 

 stations. These objects being deemed attainable by means of the 

 electric telegraph, that system was adopted, althougli it w\is of 

 greater extent than any which had been previously tried, and it 

 was executed by Mr. Cooke, one of the patentees. The telegraphic 

 wires are inclosed, for security, within \\ elded iron pipes, witli 

 screwed joints like gas pipes ; there is a duplicate set of such wires 

 and pipes, in case of one set being accidentally fractured. One 

 pipe runs along each side of the railway throughout its length. 



The machinery at the London end, for working the railway, is 

 situated at the Minories station. The carriages in coming towards 

 Lpndon are disconnected from the rope, a little before they arrive 

 at the Minories, and they perform the rest of the journey to the 

 terminus in Fenchurch-street by their momentum. The upward 

 inclination of the rails at this place is 1 in 150. 



When the down-train leaves the terminus in Fenchurch-street, 

 it descends the incline to the Minories by its gravity, where it is 

 stopped by the breaks, to allow of the passengers being received at 

 that station, and to permit the attachment of the rope ; there tlie 

 train remains for a shorttime, until signals havebeen received by the 

 edectric telegraph, from each of the intermediate stations, that the 

 carriages are ready for starting, and are properly attached to the 

 rope, in the manner already described. It being thus known at 

 the Minories that all is ready, the signal for starting is sent from 

 thence to BlackwaU ; the engines there are then put in motion 

 and begin to draw the rope with all the carriages towards Black- 

 w^l. 



At the same time that the down-train leaves the Minories, the 

 up-train leaves Blackwall, the arrangements being similar to 

 those above described. The train runs by gravity from the Black- 

 wall station to beyond the engine-house, where it is stopped by the 

 breaks, in order to attach it to the rope, and as soon as signals 

 have been received at Blackwall, from each of the intei-mediate 

 stations, that all is ready, the signal for starting is sent from 

 Blackwall to the Minories, and the engines there are put in motion, 

 and begin to draw the rope and all the carriages towards London. 

 The machinery at the Blackwall end is situated a little way along 

 the line from the terminal station ; the distance from thence to 

 the place where the carriages going to Blackwall are disconnected 

 *i — — ^ . ■ 



• 1 he uuminat power of Ihese engines is, L2-1 lioise- power lur eath j air at the 

 Minories; and 140 torse-power for each pair at Bliicltwail. There are duplicate 

 engines at each station, making 448 horse-power at the Jlinories, and 2SU horse power at 

 .BUiUiWiiU. 



from the rope, being somewhat farther from the station than the 

 engine house, and the carriages run that distance by momentum, 

 in the same manner as at the London end ; the rise towards the 

 Blackwall station being there also 1 in 150. During the winter 

 the railway is worked from half-past eight o'clock in the morning 

 until nine at night ; and in the summer, from eight o'clock in the 

 morning until ten at night. A train leaves each end every quarter 

 of an hour (giving in winter 51 trains, and during the summer 

 57 trains per day). The whole time occupied in passing between 

 the termini is thirteen minutes ; but tlie engines are at work only 

 from eight to nine minutes. The engine-house at the Minories is 

 situated beneath the railway. It is 48 feet long by 72 feet wide, 

 and the extreme length, into the recess in front of the drums is 

 69 feet. Tlie rails are carried over the machinery on cast-Iron 

 girders, which are supported at two intermediate points by cast- 

 iron pillars. The flooring over the engine-house is carried in like 

 manner upon girders. 



Beneath each line of railway there is a large drum for the rope, 

 and on the axes of each drum is a mortice spur-wheel, which 

 is driven by another iron spur-wheel of larger diameter, on a pro- 

 longation of the axis of the cranks of the steam engines ; the pro- 

 longation forming a line of shafting which extends all across the 

 engine-room, with a pair of engines at each of its extremities. 

 Only one pair of engines is worked at a time, the other pair being 

 disconnected at the cranks. Under ordinary circumstances, one 

 pair is worked for about six weeks, and then the other pair for a 

 similar period ; the object being to secure the traffic from interrup- 

 tion, by having a duplicate pair of engines always ready to be con- 

 nected at aU emergencies and in case of any accident happening to 

 the other pair, as well as to give time for the ordinary cleaning 

 and repairing of that pair of engines which is not at the time in 

 use. When one pair of engines is connected to the axis of the 

 two larger spur-wheels, the other part must be disconnected from 

 it. This is done by removing the pin of the crank on tlie extre- 

 mity of the said axis, and also removing tlie drag-link, by which 

 that pin is connected with the pin of the engine-crank, on which 

 latter pin the connecting-rod is jointed. The rope on one line 

 must be wound up round its drum, whilst that on the other line 

 is allowed to unwind from off its drum, so that the two drums will 

 revolve in contrary directions. The trains travel alternately 

 backwards and forwards on the same line of rails, instead of one 

 line of rails being always tra\elled over in one direction and the 

 other line in the contrary direction, as is the ease on other 

 railways. For instance, if the first train in the morning goes 

 down from London to BlackwaU along the north line, the second 

 train down in the same direction will go along the south line, and 

 the third train down along the north line, and so on. One end of 

 each rope is wound around one of the drums at the Minories, and 

 the other end of the same rope around a corresponding drum at 

 Blackwall ; and whenever one of those drums is turned round by 

 its engines for winding up that end of the rope, the drum at the 

 other end of the same rope must be disconnected, and left free to 

 turn round as the rojie is pulled off it. This requires some ready 

 means of disengaging either of the drums from the engines, 

 which is done by withdrawing the pair of spur-wlieels from each 

 other until their teetli become disengaged. The plummer-blocks, 

 in wliich the two ends of tlie axes of each of tlie drums revolve, 

 are mounted on rollers, and are capable of being moved horizontally 

 by screws, until the spur-wheels are out of gear. The t^^•o screws 

 for the plummer-blocks of the same drum, are moved simulta- 

 neously by gearing, worked by a handle on the platform in the 

 recess "in front of the drums; so that a man by turning that 

 handle, either connects or disconnects the geai-ing, as may be re- 

 quired. ^ 



The main axis upon which the two large spur-wheels are 

 mounted, may be considered as a single axis, but is, in fact, two 

 lengths of shaft, connected together by cranks and drag-links at 

 the mid-length of the prolonged axes, which two lengths can be 

 disconnected at pleasure, by "remo\ing the drag-links and crank- 

 pins. Hence there are two sets of machinery exactly similar, and 

 capable of being connected and disconnected in such manner, as to 

 admit of either of the two drums being worked by either of the 

 two pairs of engines, wliilst the other drum is wholly disconnected; 

 each line can thus be worked by either pair- of engines, indepen- 

 dently of the other line or pair of engines. The engines always 

 revolve in the same direction, causing the drums to wind up the 

 ropes around them ; but when the drums turn round in a contrary 

 direction for unwinding the ropes, they are disconnected from 

 tlie engines. A wheel is attached to each drum for the purpose 

 of being acted upon by a break, not only for stopping tlie motion 

 of the drum, after the arrival and stoppage of the down-train at 



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