72 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



" Every argument here adduced, and every calculation made, would tend to 

 the adoption of about 7 feet on the Great Western Railway. 



" The Gradients on the lines laid down by the Irish commission are conside- 

 rably steeper than those of the London and Uirmingham Railway, and four 

 and five times the inclination of those on the Great Western Railway; the 

 curves are by no means of very large radius, and, indeed, the commissioners, 

 after h'xing the gauge of 6 feet 2 inches, express their opinion that, upon ex- 

 amination into the question of curves, with the view to economy, they do not 

 find that the effect is so injurious as might have been anticipated, and imply, 

 therefore, that curves, generally considered, of small radius on our English 

 lines, are not incompatible with the (i feet 2 inch gauge ; and lastly, the traffic 

 instead of being unusually large, so as to justify any expense beyond that abso- 

 lutely required, is such as to render assistance from government necessary to 

 ensure a return for the capital embarked. As compared with this, what are the 

 circumstances in our case? The object to be attained is, the placing an ordi- 

 nary coach body, which is upwards of t> feet 6 inches in width, between the 

 wheels; this necessarily involves a gauge of rail of about (i feet 10 inches and 

 a half to 6 feet 11 inches, but 7 feet allows of its being done easily; it allows, 

 moreover, of a different arrangement of the body; it admits all sorts of carriages, 

 stage-coaches, and carts, to be cariicd between the wheels. And what are the 

 limits in the case of the Great Western Railway, as compared to those on Irish 

 railways? Gradients of one-fiftli the inclination, very favourable curves, and 

 probably the largest traffic in England. 



" I think it unnecessary to say another word to show that the Irish commis- 

 sioners would have arrived at seven feet on the Great Western Railway by 

 exactly the same train of argument that led them to adopt 6 feet 2 inches in the 

 case then before them. 



" All these arguments were advanced by me in my first report to you, and the 

 subject was well considered."* 



All the opinions expressed, and the arguments advanced by me on that 

 occasion, I consider to be supported by the general arguments of Mr. 

 Wood, and fully borne out by the experiments recorded in his report, when 

 taken in conjuuction with those recently made. 



The experiments made during the progress of Mr. Wood's investigation, 

 and those, few in number, which I have been enabled to make since, have 

 given much useful information upon many points connected with the work- 

 ing of the line ; and, while they confirm the views which 1 had previously 

 taken, they also point out many imperfections which are capable of 

 removal. Upon the value of gradients particul(\rly, the records of the 

 experiments made for Mr. Wood, give most conclusive evidence. Upon an 

 average of about eighty experiments made with several difterent engines, 

 and various loads upon our line (with the nuinuscript details of which Mr. 

 Wood has kindly furnished ine), the mean velocity, after the speed vi'as 

 acquired in ascending a plane of eight miles in length of four feet per mile, 

 was 302 niiles ; on a short level summit of only half a mile, the speed 

 increases to 32i; and the average of the next seven miles, on which the 

 levels vary from 4 feet to 2 feet per mile descending, the velocity was 341 ; 

 and upon the remainder of the line, which varies from 2 feet to 4 feet per 

 mile ascending, the velocity is 33|. The velocity upon the latter part is 

 rather greater, from the circumstance of its being near the conclusion of the 

 journey, the engineer being thereby enabled to reduce the feed or the supply 

 of cold water to the boiler, or to avoid adding fresh fuel and in other ways 

 to maintain the steam. 



This result gives a clear difference of four miles per hour between the 

 velocities in ascending a plane of eight miles in length, at four feet per 

 mile, and descending a plane of seven miles in length, averaging about two 

 feet six inches per mile. Nothing can be mere conclusive as to the actual 

 practical effect of even any very slight increase or diminution of the gradient 

 of a line, notwithstanding the vaguely expressed assertions — not that I 

 mean to imply that such are found in Mr. Wood's report — that after a 

 certain degree of perfection is attained it is useless to seek a nearer approach 

 to a level. 



The observations which I have lately made upon carriages moving with a 

 high velocity satisfy me that a very great portion of the resistance at such 

 velocity is caused by the rolling of the carriage wheels from side to side. 

 And in proportion as this source of resistance is removed, which it undoubt- 

 edly may be in a great measure, if not entirely, so will the useful effect of 

 the engine be greatly increased. 



I should have been glad to have taken this opportunity of entering inore 

 fully into the various questions, the agitation of which has led to these 

 experimental inquiries. But in order to comply with your desire to have 

 my observations printed and circulated this week amongst the proprietors, 

 I am compelled, though most unwillingly, to bring them to a conclusion. 



It is but justice to myself to add, that being thus limited in time, I am 

 deprived of the opportunity of which I should, under other circumstances, 

 have readily availed myself, to examine most minutely every experiment 

 and inference drawn in the report, as well as of fully explaining, and I hope 

 I may add, of vindicating, the views and principles which, with your sanc- 

 tion and approval, I have hitherto acted upon in the construction of the 

 Great Western Railway. 



I am, gentlemen, your obedient servant, 



(Signed) I. K. BRUNEL. 



London, December 27th, 1838. 



At the special ineeting of the shareholders, held on the 9tli of Jatiuary, 

 the report of the directors was approved and adopted. 



♦ Vide Mr. Brunei's Report in Journal, No. 18, pages 323 and 3S4, vol. I. 



PROCEEDINGS OF SCIENTIFIC SOCIETIES. 



INSTITUTE OF CIVIL ENGINEERS. 



[It aftbrds us much pleasure to publish the following very interesting 

 annual report of the Institute, and to announce tlie removal of the 

 Institute to premises in every way suitable to the station and rank in 

 wliich the profession is justly held by the public. The house which has 

 been lately fitted up for the members is one of the splendid mansions in 

 Great George Street, Westminster. In the rear there is a very conve- 

 nient theatre, capable of holding at the least 150 members, where the 

 proceedinas and discussions of the Institute will be conducted.] 



Anmial Report, 1839. 



It is with feelings of the greatest satislactiou, that the council invite the 

 attention of this meeting to the following report, the presentation of which 

 terminates the trust confided to them by the last annual general meeing. 



The twentieth year of the proceedings of the institution has been marked 

 by events of considerable impoitance, furnishing the strongest evidence of the 

 steady progress and success which has attended the labonrs of the council, 

 aided as it has been by the unanimous co-operation of the general body. To 

 meeton the present occasion, under circumstances more favourable than perhaps 

 attend any similar society is most gratifying ; but the gratification stops not here, 

 to form a proper estimate of your present condition, it is necessary to contrast 

 that of earlier years with the steadily increasing progress of the last. In ful- 

 filling the more extensive duties consequent on this progress, as well as on 

 the many important changes which have taken place, the council have always 

 been deeply sensible of the high responsibility committed to them, and that their 

 endeavours have been well directed, will they trust he apparent from the pre- 

 sent report, to the details of which they now solicit your careful attention. 



New Premisis- — The hopes which were at the last annual meeting held 

 out respecting the present premises have been more than fu'.ly realised. The 

 kindness of the commissioners of compensation, in resigning at midsummer, 

 that iKirfion of the premises in which the more important alterations were to 

 be made, has enabled the council to commence the session in the present place, 

 and though the repairs be yet incomplete, the council believe they will be 

 completed ere the institution again meets. The alterations and repairs will 

 be executed for about £1,000. More than £700 has been already subscribed, 

 and among the many gratifying circumstances of the past year, the council 

 would particularly select the liberality with which all have come forward to 

 further this object. 



Such has been the unanimity of feeling evinced in this respect that the 

 council believe ample resources will be foiuid, and that the future council will 

 not have to avail themselves of the liberal off'er of your president to advance 

 whatever sum the institution might require. 



The existing furniture is all available for the present premises, and the 

 outlay which will be required for what more may be desirable for your com- 

 fort and suitable accommodation will not be greater than the growing resources 

 of the institution can conveniently meet, so that there is no danger of any 

 pennanent debt being entailed on the funds of the institution. By the terms 

 of the lease you are secured from the expense of seiious repairs, and from 

 the completeness with which on the present contract they will be executed, the 

 council do nut anticipate that ariy thing further of importance will be 

 required for many years to come. 



By-laics The council would next advert to other subjects which have 



occupied their attention during the past year, some of which were dwelt upon 

 at length in the last anuual report. It mill be in the remembrance of most, 

 that during the year preceding the last annual meeting, some changes were made 

 in the constitution of the general body and of the council. The more important 

 of these changes were, the incorpoiation into the class of members, without 

 distinction of residence, of all those whose professional qualifications were recog- 

 nized as the same ; the creation of a new class under the term graduates, to 

 include those who either as pupils or assistants to engineers, were qualifying 

 themselves for the practice of the profession on their own accoiuit ; the 

 increase of the number of the council, and the addition of two as repre- 

 sentatives of the class of associates. The council, on the experience of the 

 past year, conceive that these and other important changes recommended by 

 their predecessors in office, and adopted by the general meeting of members, 

 have contributed to the success and permanent stability of the instittuiou. 



The council conceive that the introduction of two from the class of associates 

 may be attended with great benefits to the institution. This change has been 

 objected to by some zealous friends of the instituticn among the associates 

 themselves, on the ground that such an introduction might tend to divert the 

 attention of the institution from objects strictly professional. The council, 

 however, do not conceive that such fears have any just foundation, so long as 

 the rest of their body consists of men honoured by the confidence of the pro- 

 fession, but on the contrary, that the class of associates containing many 

 distinguished for their attainments in pursuits intimately connected with the 

 practice of the civil engineer, will furnish those who may co-operate in 

 advancing not only the interests of the institution, but the cause of general 

 knowledge. The council cannot omit to beartcslimony to the valuable services 

 of Mr. Carpmael and Lieutenant Denisou during the preceding year, and 

 they would repeat the recommendation made to the last annual meeting, that 

 two" of the class of associates be elected on the council of the ensuing year. 



Other alterations have been suggested, on which the council have bestowed 

 much deliberation, and in case the future council should think it advisable to 

 summon a general meeting of members to consider the propriety of making any 

 alteration in the existing laws, it may be advantageous briefly to adrert to 



