100 



ROBERT STEPHENSON, M. P 



(185S 



howeTcr, with such rapidity that they were compelled to retreat, 

 and were near being jammed against the crown of the tunnel. 

 For a considerable time all the pumping apparatus appeared in- 

 sufficient; so much so that the Directors almost determined to 

 abandon it, but the perseverance of Stephenson prevailed, and he 

 had at length the satisfaction of seeing the water recede before 

 the power of his engines. 



The tunnel is 2,400 yards in length, or neaily a mile and a 

 half; it is 25 feet wide and 28 feet high, and is ventilated by two 

 large shafts, each being 60 feet in diameter — one being 120 feet 

 deep, and the other QOrfcet ; they effect so perfect a ventilation, 

 that within a few minutes after the passage of a train, the smoke 

 and vapour is carried ct'f, so that the opposite end may be distinct- 

 ly seen. 



The time employed in constructing this stupendous work was 

 thirty months; there were 36,000,000 of bricks used in it, and it 

 cost £300,000 — nearly three times what it would had the diffi- 

 culties been of an ordinary charact :r. This line of railway has _ 

 eight tunnels of similar dimensions, that is 25 feet by 28 feet. 



The most important bridge on the line is the Wolverton 

 Viaduct, it is erected over the Ouse, near Stony Stratford, and 

 consists of six semi Eliptical Arches, each 60 feet span, the 

 roadway being elevated about 50 feet above the ordinary level 

 < f the Country. This Viaduct (except the coping which is of 

 stone) is entirely composed of brick. The aggregate amount of 

 excavation on the whole line amounted to about 15,000,000 of 

 cubic yards, being equal to an -average of 142,000 cubic yards 

 per mile, and was completed in the short space of four years 

 from its commencement. 



The above figures indicate an expensive line, and accordingly 

 we find that the favourable grades and curves have been obtained 

 »t a cost of about £42,000 per mile! 



Durino- the construction of the London and Birmingham line, 

 the Belgian Goyernment consulted Me srs. George and Robert 

 Stephenson, as to the best system of railways to be adopted in 

 that country. On their advice a cross of Trunk lines, extending 

 from Ostend to Liege on the one hand, and on the other, from 

 Antwerp through Brussels, to be connected with Mons and 

 Valenciennes" (making in all 347 miles) was adopted, and 

 nutlur'sed by law in 1834. The Stephensons were both decor- 

 ated by the King of the Belgians with the Ribbon and Cross of 

 the Leo-ion of Honor. These lines were completed and opened 

 in 1844. 



After completing the London and Birmingham line, Robert 

 Stephenson, in conjunction with his Father, undertook the con- 

 struction of various lines of railway, embracing a length of about 

 1800 miles, and for ten years were incessantly engaged in the 

 Parliamentary Contests, originating the great net work of lines 

 extending over all parts of the Kingdom. 



The Birmingham and Derby, the North Midland, York and 

 North Midland (to which the elder Stephenson chiefly devoted 

 himself), the Manchester and Leeds, and the >■ orthern and East- 

 ern, were all constructed under Robert Stephenson and his 

 Father ; and during the same period the former as Chief Engi- 

 H3er, constructed the great Iron Cross of Roads which connect 

 London with Berwick on the one hand, and Yarmouth with 

 Holyhead on the other. 



The York, Newcastle and Berwick line is one of the greatest 

 of Stephenson's works, and in its length is the magnificent High 

 Level Bridge over the Tyne, at Newcastle, and the beautiful 

 Viaduct of twenty-eight arches of 125 feet in height, and 61 

 feet 6 inches span across the Broad Valley of the Tweed at 



Berwick, connecting the North British line with the York, New- 

 castle and Berwick, and completing a continuous railway route 

 from London to Aberdeen. 



Though not personally superintending his engine manufactory 

 at Newcastle, Mr. Stephenson still continued to design and intro- 

 duce various improvements into the locomotives there manufac- 

 tured; amongst them the most important is the " Link Motion.' 

 It is probable that he was not the originator of this beautiful 

 piece of mechanism, {hough it was first applied to his engines. 

 Various arrangements of the valve-geering had been used for in- 

 troducing the expansive action of steam, and for reversing the 

 engine — while the working of the simple slide-valve was effected 

 in almost as many different modes as there were makers of 

 engines. Generally, their plans were so complicated as to cause 

 very serious expense in maintaining them in repair, and the ordi- 

 nary wear in so many working parts produced a derangement in 

 the valves, necessarily resulting in a serious loss of power. It was 

 therefore an important matter to simplify, these parts, and still 

 more important to preserve and improve the means of adjusting 

 as circumstances required, the amount of expansive action given 

 to the steam. 



To Mr. John Gray is due the merit of the first application of 

 the expansive principle by varying the travel of the valve, a prin- 

 ciple of primary importance, though originally embodied in a 

 complicated and inconvenient piece of geering. 



Mr. Cabrey, of the North Midland Railway, accomplished the 

 same effect in a more convenient form, and following up the same 

 idea, Mr. Williams, at one time of Newcastle, suggested the germ 

 of the link motion in a form, which, though rude and impracti- 

 cable, still embodied the principle : and that principle, when fur- 

 ther perfected, became in conjunction with the "lap" of the valve, 

 the most important acquisition to the locomotive since the intro- 

 duction of the blast-pipe and the multitubular flue.* 



Since the application of the link motion to Stephenson's En- 

 gines in 1843, by Mr. Howe, but little has been done to improve 

 its action — substitutes for the " link" have been proposed with 

 no very tangible object except the saving of an eccentric — and 

 though from not having been properly investigated, the correct- 

 ness of its action has been denied by some; it has been gradu- 

 ally adopted by nearly all English manufacturers, and is now 

 generally used by manufacturers in America. 



No improvement has done more to economise the cost of 

 working a railway than the introduction of the expansive prin- 

 ciple into the Locomotive, and no contrivance so perfectly accom- 

 plishes that object as the " link motion." 



* In order to exhibit the value of the lap of the valve, we introduce a 

 tabular statement ol the result of experiments made on the Liverpool and 

 Manchester Railway, in lrf42-'3, with a view to test the value of the changes 

 made in the valves,— as affecting the consumption of fuel. 



Gross consumption of Coke 



•per mile. 



49 lbs. average consumption of Company's Engines in the summer of 1S39, 



with old Valve. 

 40 lbs. average consumption of Company's Engines, after the introduction 



ol the new mode of Coke deliveries, — old Valve. 

 36 lbs. new Valves with j inch cap. 

 32 lbs. new Valves with £ inch cap. 

 2S lbs. new Valves with I inch cap, as applied to old steam and exhausting 



passages. 

 22 lbs. same Valves and same Engines, with increased care in firing, so as 



to avoid all unnecessary was'eof fuel. 

 15 lbs. Valves with 1 inch cap, as applied to the new Engines, with enlarged 



exhausting passages, larger tubes, and closer fire barf, and greater 



accuracy ol construction. 



