THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



51 



2200 feef, the train Imd to pass tbroiigli three shmits before comhig to rest, 

 which will probably account for the friction being higher than in the previous 

 experiments. 



This line, as well as the Great Western, has continuous bearings of wood. 

 Though for a short distance in the curves in all the experiments on the Man- 

 chester and Bolton Railway, the motion was continued on continuous bearings 

 of stone. The Manchester and Bolton line has a heavier rail of (.531bs. per 

 yard). And in the Great Western experiments, three of the carriiiges and 

 one wagon had six wheels each, which have rather more friction than those 

 of four wheels ; but in such a large and heavy train, no great difference could 

 be caused by this. 



The whole of the wheels in the Great Western experiments were four feet 

 in diameter, the journals 2 11-16 inches in diameter. In the experiments on 

 the Manchester and Bolton Railway the wheels were of three feet diameter, 

 and the journals of two inches diameter ; and four feet : throe feet : ; 2 1 1- IB 

 inches ; 1 1-10 or two inches nearly. But supposing that neither the fore- 

 going experiments nor reasonings are to be decisive as to the mechanical 

 advantage of increasing the size of the wheels, and 1 do not mean to say that 

 they are, for to determine the question clearly the experiments should perhaps 

 be made on the same road ; yet still as a general question there will be several 

 drawbacks on the theoretical advantage of the larger wheel, such as the 

 greater resistance on curves with the wider way ; more rubbing of the flanges 

 against the rails, not only inconsequence of the larger wheel, but of the greater 

 breadth of way ; for 1 think it is probable that friction would be reduced to a 

 minimum by concentrating the whole momentum of a train on one rail, and 

 that friction will be increased in some degree, as the distance between the 

 wheels, or as the width of way is enlarged. 



The next enquiry respecting the gauge is as to the matter of safety. If the 

 gauge is to be altered on this account, it should only be because of a want 

 of safety in the present gauge. If A be safe, there cannot be the smallest ad- 

 vantage in making B safer. 



Now the question is, is the narrower gauge safe ? It might have been rea- 

 soned a priori that the width between the railway wheels being equal to those 

 of turnpike-road carriages ; and from the very great weight of railway wheels 

 and the under carriages, the centre of gravity being in ,ill eases mueh lower on 

 a railway coach than on a stage coach ; and the railway itself being infinitely 

 more smooth asd perfect than the common road ; that though the velocities are 

 much greater, yet still there isnodanger of overturning. And the fact is, 1 have 

 never heard ofa ease of overturning, or of any accident that I should attribute 

 to the narrowness of base, occurring. And from what experience I have had 

 on Railways, I believe it would be a most difficult matter to overturn the 

 carriages upon them, with the present gauge, even if the object was purposely 

 to do so, and an experiment should be made for the purpose. But having 

 heard it urged that there was greater safety on the wider base, which may be 

 granted, but which amounts to little if there is quite enough of safety on the 

 narrower base ; and being unfible to call to mind a single instance of an acci- 

 dent or of an overturning in consequence of a narrower base, 1 addressed a 

 letter to Mr. Booth, the treasurer of the Liverpool and Manchester Railway, 

 on the subject, to know if he had ever known an accident that could be at- 

 tributed to the narrovvnessof base; I also wrote a similar letter to Mr. Smith, 

 engineer on the Leeds and Selby Railway, and I received the following re- 

 plies : — 



" Liverpool and Manchester Railway, 



" Lime Street Station, 21st Sept., 1838. 



" Sir, — I have to acknowleilge the favour of yom* comnmnieation of the H)lli, 

 cni|uiriug whether or not, in my experience, there is any want of safely in the present 

 gauge, 4 feet 8^ inches as^to the chance of overturning; and also iV I have known 

 any case of overturning in consequence of narrowness of base, or are aware of any 

 accidents having occurred, which I would ascribe to the narrowness of the l feet 

 8A inches, base. 



" In reply, I beg leave to inform you that in my opinion there is not auy want of 

 safety in the 4 feet 8^ inch gauge, and I am not aware of any accidents having 

 occurred, which I shoiUd ascribe to the 4 feet 8J inch gange. The only case of 

 overturning which I recollect occurred some years ago, when, owing to the breaking 

 of an axle, the engine (which had only four wheels) ijuitted the rails, and drc\v 

 several of the carriages over the embankment, near Bury-lane. 



" Wliether in such a case a broader base would have prevented the carriages over- 

 turning, I will not pretend to say ; it might depend on the relative heiglit of the 

 carriages and other circumstances. " I am. Sir, &c., 



(Signed) "He.n'ky Bootu." 



" John Hawkshaw, Esq." 



"Leeds, 21st Sept., 1838. 

 •■ Dear Sin,— In reply to yours of the 10th inst., wc have had but one accident 

 (during the experience of four years) that w:is not occasioned either by tongues 

 being wrong or some obstacle m the way The one excepted, was caused by the 

 repairers raising some wood sleepers too mnch at once on a new made embankment. 

 I do not consider there is any want of safety in the gauge, (4 feet 8A inches) nor do 

 1 know of any accident or overtuniuig which can be attribnted to that guagc. 



" I am, dear Sir, yours, i;c., 

 (Sigucd) "Geo. Smith, R.K., 



" John Hawkshaw, Escp" " Leeds and Selby Railway." 



Besides, there is no ditficulty in lowering the centre of gravity on the pre- 

 sent gauge very considerably, were such a thing desirable or called for. For 

 by making the coaches omnibus fashion, the passengers in each coach could 

 be made to sit a foot lower than at present. That this is not dune goes a 

 great way to prove that it is unnecessary. Or by keeping the centre of 

 gravity as it is, it is quite easy and practicable with the present gauge to in- 

 crease the siie of the wheels from three feet to three I'ect sw iuelics or larger, 

 if any thing was to be gained by it. 



Having gone into the question of gauge abstractedly from what has been done 

 upon your line in connection with it, and debiting the system of a 7 feet rail 

 with such an increase of cost only as appears to me to be absolutely conse- 

 quent on its adoption, I feel compelled to come to the conclusion, that there 

 are no advantages to be obtained by adopting it, at all commensurate with 

 the evils that will be consequent on the deviation; and for the reasons which 

 follow, it is not desirable, in my opinion, to proceed with it, unless you were 

 already committed to it in a pecuniaiy sense, to an amount that will outweigh 

 all the objections to it, but which will be seen hereafter. 



The additional reasons for not proceeding with it are these; — first, consi- 

 deiing the great cost, and the comparatively small profits of railway lines 

 generally on the smallest dimensions, and the great difficulty theie is, and the 

 corresponding increase of outlay that is incurred, in obtaining curves of suffi- 

 ciently large radius to be workable at the present narrower gauge ; I cannot 

 conceive that there is a single practical man in England who could recom- 

 mend the 7 feet gauge, as general system for this country. 



If unfit as a general system for the whole country, it will be unfit as a par- 

 tial system for a portion of it ; unless that system is of necessity to be very 

 mueh confined ; its ramifications into other di.stricis impossible from natural 

 barriers, such as seas, or lakes ; and the nature of the country, such as to un- 

 dulations, that the cost of obtaining curves of larger radius will be trifling. 



Even admitting that the latter condition is true of your line, and that from 

 its general flatness curves can easily be obtained of large radius, yet this 

 cannot be predicated of the whole of the branches and extensions to which 

 you will have to look for collateral and extended traffic. And even if it could, 

 still the system is unquestionably more expensive to some degree, and though 

 you with your large traffic might not be totally crushed by it, it has yet to be 

 seen what the effect will be on the smaller and less favourable lines; which, 

 to get into yours, will be compelled to adopt similar dimensions, and involv- 

 ing of course similar expenses. At the same time, the prosperity of your 

 line will be affected in no small degree by the prosperity of the tributaries to 

 it ; and in fact, a probable result of doing things on such a great scale will 

 be, to drive traffic which otherwise would come upon you, in some other direc- 

 tion. For in railway lines generally, in the same country, there will come to 

 be .1 mutual dependance one upon another. And surely it must be rather an 

 untenable doctrine to hold, that the gauge of each line is to be determined 

 only by reference to its curves and gradients, for by such a rule it would 

 follow that no two lines could be alike. 



Finally, it may be said of railway lines, that they will not bear any addi- 

 tional expense. It may perhaps be said of every railway formed in this 

 kingdom, that if the company had to begin again, their object would be to 

 economise, and to diminish their first outlay, not to increase it ; or if there be 

 a railway company, and such are rare cases, that has already devoted its atten- 

 tion to the utmost in keeping down the expenditure in the first instance — that 

 railway company would not do otherwise if it had to begin again ; and that 

 railway company will feel that for the course that has been pursued, there is 

 every cause for congratulation. 



I could not advise you to take the London and Birmingham as your model, 

 and feel satisfied if you exceed them as to cost in only a few particulars ; 

 their line was necessarily through a country very different, and far more e.K- 

 pensive than yours ; and their line is in a position in which, if a great ex- 

 penditure is to be repaid anywhere in this country, it will be to them. For 

 I cannot conceive that your line, or indeed any other line that I am acquainted 

 with, can expect an equal amount of thorough traffic ; for into their line a 

 great portion of the north of England, and a still larger portion of Scotland, 

 besides the great manufacturing and commercial districts of Birmingham, 

 Manchester, and Liverpsol, must of necessity converge before arriving at the 

 Metropolis. 



Still, though I do not see that the aggregate of your traffic can ever be e.x- 

 pected to equal that of the London and Birmingham ; yet, considering the 

 much more favourable country through which your railway passes, and that 

 the traffic upon it will be unquestionably very large, I think your line pre- 

 sented equally as good features for investment, and perhaps may do so still ; 

 it will depend, in my view, upon the course you pursue. 



That course, as far as my opinion goes, is not to go forward on your present 

 system. Knowing that railways hitherto, and on the smaller scale, have been 

 found greatly expensive, so much so as scarcely in any case to leave an ample 

 dividend, when the great risk of such investments is considered, I cannot 

 advise you to proceed on a plan which, in all human probability, will mate- 

 rially diminish that dividend. 



It cannot be necessary for the attainment of safety, when in the present 

 gauge there is no danger. 



It cannot be required for the attainment of high velocities, because on the 

 narower gauge velocities can be attained with perfect safety, greater than, 

 could be maintained by any railway company in England perhaps, without 

 absolute ruin to themselves in a pecuniary sense. 



The Liverpool and Manchester Railway, by increasing their speed from 20 

 to 2l) miles per hour, have iucrciiscd their locomotive expenses about 15 per 

 cent. Much higher velocities ttan this arc attained, and with perfect safety, 

 on the narrower gauge ; but there is no company that could bear the increased 

 expense of maintaining such velocities constantly, or if there be, it will be 

 fcund to be that company which has expended the least in the first instance. 

 For example : the Grand Junction would feel the effects of increased expen- 

 diture to maintain a very high velocity, loss than would the Loudon and Bir- 

 mingham ; not that their gradients are better, they are worse; but simply 

 because their first outlay is much less, and therelbre their annual expenses 

 might be much increased, and still leave as large a revenue: in short, for very 

 much the saijie reason that 20s, for carrying ^ passenger 97^ miles oii theii 



