i846.] 



THE CIVIL ENGINEEERAND ARCHITECT'S JOURNAL 



207 



Midlands S/'^S 



North I'nion . . . . • ""sO 



York and Norlh Midland . . . "J.l'J^ 



Tnii Tivi/^e.— The fdilowins shows tI)P sross tonnase and amounts re- 



eei»ed on the iind.Tnieniinned lines io the year beginning 1st July, 1844, 



aud ending 30th June, 1815 : — 



Arhroalh and Forfar 

 Ardrossan 

 Balloiliney 



Bristol and Birmineham . 

 Canterbury and U'hitstable 

 Clarence . 

 Ounferudine 



Hurhiiin and Sundeiland . 

 rdinburgh and Dalkeith . 

 Olassow and Ayr 

 Glassow and Garnkirk . 

 Great North of Enf;land . 

 Harilepool 

 Ha>le 



Leicester and Swannlngton 

 Liverpool and Mani-hester 

 Llanelly and Llanililo 

 London and Croydon 

 London and Sotiih Eastern 

 London and Brighton 

 London and South Western 

 Manchester and Bury 

 Marvport and Carlisle 

 Midland , 



Newcastle and Carlisle . 

 Newcastle and narliii^too 

 Newcastle and North shields 

 North Union 



Pontop and South Shields 

 Preston and Wyre 

 St. Helens and Runcorn Gap 

 ShefSt-ld aud Manchester 

 Slieflield and Kotherhain 

 Stockton and Darlington 

 Tatr Vale 

 Ulster 



Whitby and Pickering 

 \V)«liaw and ('tdtness 

 York and North Midland 

 Bale per mile for toll only, and for total charges : — 



Canterbury and Whitsfable . 



Dunfermline and Charlestown 



Bodmin and W'adebridge 



Hayle . 



Dundee and Newtyle . 



Maryport and Carlisle 



Arbroath and Forfar . 



Monklaad and Kirkiotillocb 



South Western 



Wishaw and Coltness . 



Manchester and Bury 



London and Croydon . 



South Eastern 



Brighton 



Newcastle and Carlisle 



Leicester and Swannington 



Llanelly and Llandilo 



Bristol and Birtniniiham 



Durham and Sun-Ierland 



St. Helens and Uunrorn Gap 



Pontop and South Shields 



Garnkirk and (ilasijow 



Newcastle and Darlington 



Edinburgh and Dalkeith 



Preston and Wyre 



Taff Vale 



Manchester and Leeds 



Clarence 



Hartlepool 



York and North Midland 



Great North of England 

 The above are not in all cases the average charges, but the maximum 

 oharges ; as on 'nmi lines, a higher rate is charged for going up hill thaa 

 far going down bill. 



VIBRATION OF TRAINS IN TUNNELS. 



Report on the vibration proilucid hij trains in passing tUrough the tunnel of 



liiHsiil Green. To R. Stiphenson, Esq. 



Sir — I hare the honour to submit to you the results of the series of ex- 

 parinients perforjned at Ken.sul Green, with the view of ascertaining to 

 what distance the vibration produced by a train in passing through the 

 tunnel may be sensible. 



In these experiments. I employed a basin of quicksilver, which was 

 placed on the ground and fixed as tirmly as possible. A lens carrying a 

 set of cross wirts wan attached, in such manner that the imaxe of the 

 wires could be reflected in the mercury, and therefore any vibration of the 

 mercury could be easily detected by the oscillation of the reflected image. 

 A piece of glass etf.'ctually protected the mercury from currents of wind, 

 and the experiments were thereby rendered very satisfactory. In observ- 

 ing tl>e reflected wires. 1 did not employ a telescope, as a previous trial 

 had convinced me that no material advantage would arise from the use of 

 a lelesci>pe, since the sensibility of the eye in detecting the least vibration 

 of the mercury was far greater than I could have exoecled, and more than 

 sullicieully dflicate for the purpose in view. 



The situation selected was a field belonging to Mr. Sullon, on the north 

 side of the tunnel. Th.* distances were measuied with a land chain from 

 the northern side, as nearly as its position could be ascertained. 



April lOih. — The day cloudy, but without rain, a moderate breeze blow- 

 ing from the eastward. 



Distance liO feet. Down train very great vibration, the reflected image 

 of wires was quite invisible from agitation as the train approached the 

 centre of the tunnel ; the vibration commenced immediately the train en- 

 tered the tunnel, and ceased the moment that it left. 



Distance 138 feet. Down train — the vibration began about two seconds 

 after the train entered, and ceased about the same tune before it was out 

 of the tunnel ; though the amount of oscillation was much less than at 

 60 feet, it was still considerable. 



Distance 30.< feet. Down train— the vibration began immediately the 

 train was in the tunnel, and continued about ten seconds alter it had left ; 

 the train was in the tunnel twenty seconds. 



Distance 472 feet. A heavy down train — thirty-two seconds in passing 

 through the tunnel. The vibration was seen about seven seconds after it 

 was in the tunnel, and ceased four seconds before it left. The amount was 

 rather considerable. 



Distance 572 feet. Up train — twenty seconds in tunnel. The oscilla- 

 tion of the mercury was sensible five seconds alter the train entered, and 

 ceased ten seconds before it emerged from the tunnel. Another up train 

 produced the same i li'ect. 



Distance 644 feet. A down train — twenty seconds in the tunnel — pro- 

 duced not the slightest effeei. The obsei vulion very salisfactory. 



Distance 609 feet. A down train — twenty-seven seconds in the tunnel. 

 The vibration so excessively small as to be visible only by transient 

 glimpses when the train was lairly in the tunnel. I consider this to be the 

 distiince where the ribration becomes sensible, and beyond U the trams Wilt 

 have no perceptible effect in this locality. 



The following estimated values for the amount of vibration, though ne- 

 cessarily very rude approximations, may still be interesting : — 



Distance 60 feet. Amount of vibration 100 



138 „ „ 40 



300 „ „ 25 



„ 472 „ „ 10 



„ 572 „ „ 5 



609 „ „ 1 



044 „ „ 



On April 11th, some observations were attempted in a field adjoining 

 that belonging to Mr. Sulion, at a distance from the tunnel of 400 feet, 

 but the perpendicular drawing from the place of observation to the tunnel, 

 would fall not more than 50 ftet from the entrance, and this circumstance, 

 in addition to most unlavoniable weather, probably prevented my seeing 

 any vibration. An objection being raised on this day against the perform- 

 ance of the experiments on iMr. Su lion's propel ty, I was unable to proceed 

 until the 15th, when that gentleman was kind enough to allow me the use 

 of the field on the north side of the tunnel, a most favourable locality for 

 the purpose. 



On April I5th, I made some experiments to ascertain whether a hori- 

 zontal wire of a transit telescope placed at difierent distances from the 

 tunnel to bisect a distant objrcl would show tiie vibration at those dis- 

 tances to be sensible. I very soon found that this method was not suf- 

 ficiently delicate, as no vibration could be detected even at 60 feet distance 

 from the side of the tunnel. The experiments with mercury on the follow- 

 ing day were made under very favourable circumslauces, aud the results 

 are, I believe, worthy of great confidence. 



Mr, Biship's Observatory, Regent's Park, 

 April 17, 1846. 



J. R. HiNU. 



