442 



NATURE 



\August 31, 1882 



bridges, aqueducts, canals, river navigation and "docks, for in- 

 ternal intercourse and exchange, and in the construction of ports, 

 harbours, moles, breakwaters, and lighthouses, and in the art of 

 navigation by artificial power for the purposes of commerce, and 

 in the construction and adaptation of machinery, and in the 

 drainage of cities and towns." This definition, written more 

 than half a century ago, is wide enough to include all branches 

 of engineering of the present day, although amongst those spe- 

 cifically mentioned the departments presided over by the railway 

 engineer, the locomotive superintendent, and the electrician will 

 be looked for in vain. As Telford was beyond all question the 

 most widely experienced and fur-seeing engineer of his time, 

 this little omission well illustrates and justifies my statement that 

 the . typical civil engineer of the day is a late product of the 

 present century ; for even Telford never foresaw the vast changes 

 which railways, steam, and electricity would evolve in the course 

 of a few years. 



My predecessors in this chair have on several occasions stated 

 their conviction that it w as better for the author of an address to 

 confine his attention to the particular department of engineering 

 in which he had special knowledge, than to wander over the 

 whole field of mechanical science. A well-informed man has 

 been defined to be a man who knows a little about everything 

 and all about something. If you give me credit of being a well- 

 informed engineer, 1 will endeavour to justify your good opinion 

 by showing, whilt presiding at these meetings, that 1 know a 

 little about steam-navigation, and machinery generally ; a little 

 about iron and steel, and other manufactures, and I trust a gcod 

 deal about the construction of railways, canals, docks, harbours, 

 and other works of tha< class. 



There have undoubtedly been published during the last fifty 

 years many works of mark and merit, but the work which above 

 all others would, I think, have astonished and perplexed our 

 ance.-tors, is the little one known to all the civilised world as 

 "Bradshaw." '1 his indispensable handbook of the nineteenth 

 century testifies that the face of the country is dotted over 

 literally witb thousands of railway stations ; that between many 

 of these stations trains run at two-minute intervals, whilst the 

 distance between others is traversed at a mean speed of nearly 

 60 miles an hour. The public are often justly indignant at the 

 want of punctuality on some railways, but they should blame 

 the management, and not the engineers, for the daily conduct 

 of the heavy traffic between England and Scotland shows, that 

 notwithstanding the constantly varying condition of wind and 

 weather in this climate, a run of four hundred miles can, on a 

 properly laid out railway, and with suitably designed rolling- 

 stock, be aco ni| lished with certainty to the minute, if the 

 management is not at fault. On the Great Northern Railway, 

 for instance, cf which I am consulting engineer, the 400 miles 

 between London and Edinburgh is traversed in nine hours, or 

 deducting the half-hour allowed at York for dining, at the mean 

 rate of no less than 47 miles per hour including stoppages. A 

 few months ago the Duke of Edinl nrgh was taken on the same 

 line of railway from Leeds to Lt ndon, a distance of 1865 miles, 

 in exactly three hours, or at a mean rate, including a stop at 

 Grantham, of over 62 miles an hour. I know of no railway 

 in the world where this performance has been eclipsed, and 

 it will be perhaps both instructive and amu-ing to contrast with 

 it the performance of the engines at the opening ceremony of the 

 Liverpool and Manchester Railway, on .September 15, 1830. 

 A newspaper correspondent of the time, after describing many 

 eventful incidents of his journey, proceeds as follows:"" "The 

 twenty-four vehicles left behind were now formed into one con- 

 tit m us line, with the three remaining engines at their head, and 

 at twenty minutes past five o'clock we set out on our return to 

 Liverpool. The engines not having the power, however, to 

 drag along the double load that had devolved upon them at a 

 faster rate than from five to ten miles an hour (once or twice 

 only, and that but for a few minutes, did it reach the rate of 

 twelve miles an hour), it was past eight o'clock before we reached 

 Parkside. Proceeding onwards, we were met on the Kenyon 

 Embankment by two of the missing engines, which were im- 

 mediately attached to the three which had drawn us from Maa- 

 chester. We went still slower than before, stopping continually 

 to take in water (query to take breath), and creeping along at a 

 snail's pace till we reached Sutton inclined plane, to get up 

 which the greater part of the company were under the necessity 

 of alighting and making use of their own legs. On reaching 

 the top of the plane we once more took our seats, and at ten 

 o'clock we found ourselves again at the company's station in 



Crown Street, having accomplished the distance of .33 miles in 

 four hours and forty minutes." 



The incident of the passengers de cending from a train headed 

 by five engines to walk up an insignificant incline is, I think 

 worthy of being recalled to the remembrance of the travelling 

 public who are accustomed to see without astonishment a single 

 engine rushing along with a train of a dozen heavy carriages at 

 as high a speeel as if it were running alone. We must do our 

 immediate forefathers, however, the justice to remember that 

 even they effected some considerable improvements in the speed 

 of locomotion. For example, in 1763 the only public con- 

 veyance for passengers between London and Edinburgh was a 

 single coach, which completed its journey in fourteen days, or 

 at the average rate of 1^ mile per hour. Strange as it may 

 appear, there are at the present time many large fertile districts 

 in Hungary where, owing to the absence of both road and water 

 communications, a higher rate of speed cannot be attained in a 

 journey of seven day's duration. 



An essential condition of the attainment of high speed en the 

 railway, is that the stopping places be few and far between. The 

 Great Northern express previously referred to makes its first 

 halt at Grantham, a distance of 105 miles from London, and 

 consequently but little power and time are lost in accelerating 

 and retarding the speed of the train. In the instance of the 

 Metropolitan Railway, on the other hand, the stations average 

 but half a mile apart, and although the engines are as powerful 

 as those on the Great Northern Railway, whilst the trains are far 

 lighter, the average speed attainable is only some twelve miles an 

 hour. No sooner has a train acquired a reasonable speed than 

 the brakes have to be sharply applied to pull it up again. As a 

 result of experiment and calculation, I have found that 60 per 

 cent, of the whole power exerted by the engine is absorbed by 

 the brakes. In other words, with the consumption of 30 lbs. of 

 coal per train mile, no less than 18 lbs. are expended in grinding 

 away the brake blocks, and only the remaining 12 lbs. in doing 

 the u eful work of overcoming frictional and atmo-pheric 

 resistances. 



Comparatively high speed and economy of working might be 

 attained on a railway with stations at half-mile intervals if it 

 were ] ossible to arrange the gradients so that each station 

 should be on the summit of a hill. An ideal railway would 

 have gradients of about I in 20 falling each way from the 

 stations with a piece of horizontal connecting them. With such 

 gradients gravity alone would give an accelerating velocity to 

 the departing train at the rate of one mile per hour for every 

 second ; that is to say, in half a minute the train would have 

 acquired a velocity of 30 miles an hour, whilst the speed of the 

 approaching train would be correspondingly retarded without 

 the grinding away of brake blocks. Could such an undulating 

 railway be carried out, the consumption of fuel would probably 

 rot exceed one half of that on a dead level railway, whilst the 

 mean S| eed would be one-half greater. Although the required 

 conditions are seldom attainable in practice, the broad principles 

 should be kept in view by every engineer when laying out a rail- 

 way with numerous stopping places. 



Nearly thirty years ago, w hen projecting the present system of 

 underground railways in the metropolis, I forcaw the inconveni- 

 ences which would necessarily result from the use of an ordinary 

 locomotive, emitting gases in an imperfectly ventilated tunnel, 

 and proposed to guard against them by using a special form of 

 locomotive. When before the Parliamentary Committee in 1854, 

 I stated that I should dispense with firing altogether, and obtain 

 the supply of steam necessary for the performance of the single 

 trip between Paddington and the City from a plain cylindrical egg- 

 ended boiler, wdiich was to be charged at each end of the line with 

 water and steam at a high pressure. In an experimental boiler 

 constructed for me, the loss of pressure from radiation proved 

 to be only 30 lbs. per square inch in five hours, so that practi- 

 cally all the power stored up would be available for useful work. 

 I also fuiind by experiment that an ordinary locomotive with the 

 fire "dropped " would run the w hole length of my railway with 

 a train of the required weight. Owing to a variety of circum- 

 stances, however, this hot-water locomotive was not introduced 

 on the Metropolitan railway, though it has since been success- 

 fully used on tramways at New Orleans, Paris, and elsew here. 

 I am sorry to have to admit that the progress of mechanical 

 I science, so far as it affects locomotives for underground railways, 

 , has been absolutely «;/ during the past thirty years. The loco- 

 motive at present employed is an ordinary locomotive, worked in 

 the ordinary way, except that in the tunnel the steam is con- 



