224 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[.Tune, 



THE KILSBY TUNNEL. 



Tlio Kilsliv Tuiiuel is about 2,423 yards long, and was intended at fust (o 

 be formed eighteen inrlies thick in the bricliworlc ; but it was found neces- 

 sary to increase tliis, in nio^t cases, to twenty-seven inclies. The whole lias 

 been built in either Roman or metallic cement. 



Tiie worlis were commenced in .hme, 183.5, by the contractors; but such 

 serious difhculties were met with, at an early stage of the proceedings, that 

 they gave up tlie contract in March, 183f>, and nearly the whole work lias 

 been performed by the company. Previous to the commencement of the 

 works, trial-shafts were sunk in several parts of the line of the tunnel, in 

 order that the nature of tlie groinid through whicli it would have to pass 

 might be ascertained j and it was found to be generally lias shale, with a few 

 beds of rock — in some places dry, in others containing a considerable quan- 

 tity of water.* 



In sinking the second working-shaft, it was found that a bed of sand and 

 gravel, containing a great quantity of water, lay over part of the tunnel ; and 

 this was such a perfect quicksand, that it was impossible to sink through it in 

 the ordinary way. By repealed borings, in various directions near this jiart 

 of the tunnel, the sand was discovered to be very extensive, and to be in 

 shape like a llat-bottomed basin, cropping out on one side of the hill. The 

 trial shafts had accidentally been sunk on each side of this basin, so that it 

 had entirely escaped notice until the sinking of tlie working shaft. 



Mr. Stephenson was led to suppose tiiat the water might be pumped out, 

 and that under the water thus drained the tunnel might be formed wiih com- 

 parative facility; this proved to be the case. Engines for pumping were 

 erected, and shafts sunk a little distance out of the line of the tunnel. The 

 pumping was continued nearly nine months before the sand was sntficiently 

 dry to admit of tunnelling, and during a considerable portion of that time 

 the water pumped out was 2,t100 gallons per minute. The quicksand extended 

 over about 4-JO yards of the length of the tunnel, and its bottom dipped to 

 about six feet below the arch. 



In May, 1836, one of the large ventilating shafts was commenced, and 

 completed in about twelve months. This shaft is sixty feet in diameter, and 

 132 feet deep ; the walls are perpendicular and three i'eet thick throughout, 

 the bricks Ijeing laid in Roman cement. The second.ventilating shaft is not 

 so deep by tliirty feet. These immense shafts were all built from the lop 

 downwards, by excavating for small portions of the wall at a time, from six to 

 twelve feet in length and ten feet deep. 



In November, I83f), a large quantity of water burst suddenly into the 

 tunnel, in a part where there were no pumps; it rose very rapidlv, and in 

 order to prevent the ground being loosened by it at the far end, where il was 

 excavated, a rather novel mode of building the brickwork was resorted to. 

 This was by forming a large raft, and on this the men and their materials 

 were floated into the tunnel, and with considerable difficulty and danger per- 

 formed their task. 



All the difficulties were at last conquered, and the tunnel finished in 

 October, 1838 ; but, of course, the expenses were increased to a very great 

 extent. The directors fell it to be their duty not to restrict the proper outlav 

 of capital, when satisfied it would secure the convenience of the ])ublic, the 

 stability of the works, and the efficient management of the traffic ; and thev 

 felt persuaded Ihat a perseverance in this course, to the completion of the 

 undertaking, would be found most economical in the end, and best calculated 

 to ensure the permanency of that successful result which is now happilv 

 placed beyond the reach of doubt. The contract fen- making the Kilsby 

 Tunnel was 99,000/., and it has cost more than 300,000/., or upwards of 130/. 

 per j-ard. 



To give some idea of the magnitude of this work : — There were thirty 

 millions of bricks used in it, which, at ten hours for a working day, if a man 

 counted fifty in a minute, would take one thousand days to get through them 

 all. Tliere were above a million of bricks employed in the deepest venti- 

 lating shaft, and its weight is 4,034 tons. The weight of the whol« tunnel is 

 118,620 tons; or it would freiglit four hundred ordinary merchant ships, of 

 about three hundred tons each ; and if these bricks were laid end to end, they 

 would reach 4,260 miles. The quantity of soil taken from the tunnel was 

 177,452 cubic yards. 



The great ventilating shafts are perfect masterpieces of brickwork, and are 

 found fully to answer the pui-pose for which they were intended, leaving the 

 tunnel entirely free from any offensive vapour iunnediately after the transit of 

 each train, and their magnitude can only be estimated by standing in the 

 tunnel and looking upwards. 



The passage through this mighty work of engineering skill and ingenuity 

 leaves on the mind, even of tliose unacquainted with the ordinary difhculties 

 of such an undertaking, a vivid impression of the rare talents of those who 

 designed the work, and superintended its execution. These talents, however, 

 will be more especially appreciated by those who are aware of the many and 

 unforeseen obstacles which arose during its progress. To Mr. Charles Lean, 

 the assistant engineer under whose direction it was completed, great credit is 

 due for his skill and unremitting exertions, and for the great care he bestowed 

 upon the men in the ai'duous and dangerous duties in which thev were con- 

 stantly engaged. * * . « ' » 



The history of the great railway between London and Birmingham is now 



• Orgcinu- remams at Kitsby are very numerous. In some parts of the excavation 

 there is hardly a cubic inch without shells and other remains nvesentint; tliemselves to 

 the eye, and as the eanh taken out has been princiiiallv laid into spoil, there will be 

 ample opnortunitics, for some tune yet, for further exammation. which would well 

 repay either the scientific inquirer or the cabinet collector. 



finished. A wonderful work it is to look ujton, whether it be contemplated 

 in its magnitude and difficulties, its science and capital, or its utility and 

 results. It stands as much the monument of this age as any of the great 

 works of antiquity that have been the subjects of the world's history. There 

 is, however, this diflerence in its favour, that while they have been raised in 

 tlie cruel exercise of despotic power, and have mainly subserved the purpose 

 of personal vanity, this has been accomplished by the jirofitable euiplovnient 

 of the redundant capital of a single district, to meet the wants of a vaslly- 

 iinproved people, and is the triumphant invention of science, trained and 

 disciplined under severe study, imd gathering accelerated strength from the 

 successful experiments of each succeeding year. The flexible power of steam 

 was, indeed, known to the philosophers of former times ; but they used this 

 knowledge only for the fantastic puqioses of caprice and amusement. 

 -Anthemius, in the age of .Tustinian, employed his actinainfance with this 

 principle to annoy a troublesome neighbour, and by imitating an earthquake 

 frightened /.eno out of his house ; and, at an after-period, Pope Silvester 

 invented an organ, which was set in motion and worked by it. It is the 

 glory of the present era, that science and utility go hand in hand to advance 

 the improvement and happiness of the nation. 



Every age of the world has furnislied its own peculiar inventions, and these 

 Iiave generally been well adapted to the wants that suggested them, and to 

 the condition in which society was at that time placed. Il is a subject more 

 tlian commonly interesting to contemplate genius toiling amidst so many 

 difficulties, and by patient perseverance overcoming all perplexity and 

 opposition. It is, perhaps, still more interesting to observe it under the trials 

 of its first experiments, amidst the doubts, imbolief, and sometimes jeers, of tho 

 multitude, self-possessed in the truth of its principle, yet tremulously fearful 

 while lying at the mercy of the thousand contingencies that might thwart or 

 destroy its hopes and expectations. Such was the case with Telford, on the 

 final erection of the famous hanging bridge over the Menai Straits. It is said 

 that his heart sunk as every successive bolt was struck, till overcome with the 

 agony of his feelings, he retired to his cottage hard by, and awaited on his 

 knees the result. The shouts of the admiring populace, when the wonderful 

 fabric settled into its place across the turbulent waters, and his own almost 

 inarticulate thanksgiving in his secret chamber, aro.se together in the triumph 

 of that hour. 



When poor Henry Bell, after years of thought, labour, and experiment, 

 first pushed his steam vessel on the Clyde, it was done amidst the scofls and 

 evil surmises of those who assembled to witness the scene. The inventor 

 died in poverty ; but an obelisk that rears itself on the banks of that fine 

 river, near Dunglass, attests the tardy, and to him almost useless, gratitude 

 of his countrymen. Fulton embarked on the Hudson with the same con- 

 temptuous greetings and prognostications, from the very people who 

 assembled in thousands to hail the arrival of the Groat VVestei-n and Sirius 

 steamers, across the vast Atlantic, to their omi .shores. He lived to see, and 

 in some degree to share, the complete success of his genius and mechanical 

 skill.* How deeply we are indebted to these children of science who carried 

 forward their discoveries, — in the benefits of which we so largely participate, — 

 almost broken-hearted, amidst the chilling indifference or the withering 

 contempt of a selfish world ! 



The work of which we have been treating has involved nearly, if not allo- 

 gefher, a capital fif six millions of money in its completion. This enormous 

 amount will require three hundred thousand pound per annum, merely to pay 

 its interest, at five per cent., besides a very considerable sum in addition, to 

 defray the wear and tear, and other expenses of its yearly operations ; and 

 yet with all this immense outlay, il is certain, from tlie host of travellers it 

 will allure into a state of locomotion from pleasure or profit, and the various 

 lines that will eventually flow into it, that it will be one of the most pro- 

 ductive railways in the kingdom. We cannot, indeed, clearly foresee the end 

 of such an invention, of which this is one of the greatest experiments, or the 

 condition of society it may ullimately produce ; but we arc warranted in 

 believing that this onward state of improvement, by facilitating and enlarging 

 the sphere of social communication, will tend greatly to increase the amount 

 of social happiness; and in its combining and assimilating influences over tho 

 great human family, will assist in bringing about the benevolent purposes of 

 Him, " who hath made of one blood all nations of men for to dwell on all the 

 face of the earth." 



EXCAVATIONS ON THE LONDON AND BIRMINGHAM RAIL- 

 WAY BETWEEN SHELDON BROOK AND YARDLEY. 



A novel and ingenious method of excavating was first tried, f under the 

 skilful direction of the assistant engineer, Mr. R. B. Dockray, a gentleman 

 who now holds the appointment of resident engineer for one half the line, 

 having before superintended the division from Birmingham to Hampton, 

 which is executed in such a superior manner as fully to justify the high 

 opinion formed in every quarter of his eiigineering abilities. To estimate the 



plan properly, it will be necessary to desciibe the old system of operations : 



On commencing the work a deep trench or gullet was cut, ten or twelve feet 

 deep, and as many wide, at a suitable inclination for removing the excavated 

 materials. When this gullet was carried quite through the liill, the sides 

 were cut away to the edge of the slopes by " falling" — thai is, by undermining 

 at the bottom and driving wedges from the top and a few feet f^rom the face, 



* The engine used by Fulton, in Ills first steam-boat on the Hudson river, was made 

 bv Messrs. lioultun and Watt, of .Soho. 

 '+ By Mr, Xhoiutun, wntractor f»t the work» 



