8.3 



STEAM-CAUUIAUKS. 



STEAM NAVIGATION. 



801 



(In the preceding article the formula- expressing the iiliysio.il anil 

 mechanical properties of (team will be found, ami for the others the 

 following works mnong others may be consulted : Tredguld, T., On the 

 }<t.-ttn-Knyine ; Farey, J., (hi tke Ktean-Emjine, 4to. ; Ue Pambour, 

 F.M.K., Chev., Thtorie tit la Machinr A Vapewr, 8vo. ( Paris ; (Jail.. way, 

 () Ihr Hit ,1111 f.'n ihir, and others.) 



STKAM-r.\Ki;iA<;KS on common roads have for many years occu- 

 pied the attention nf engineers ami mechanicians, on account of the 

 'it tomomy which would result from th* use of a raid surface 

 adapted to. and previously constructed for. ordinary traffic ; but, up tu 

 the present time, none of the systems which have been proposed for 

 the count ruction of these engines can bo considered to have entirely 

 overcome the practical difficulties attending the transport of th 

 weights required in the machinery and Killers, or the variable resist- 

 ance* encountered. Some of the more recently introduced traction 

 engines seem, however, to contain, in genii, the elements of the success- 

 ful solution of the problem of steam locomotion, by engines of small 

 power, running on roads possessing an inferior degree of theoretical 

 perfection than well maintained railways ; and the introduction of the 

 street railways certainly justifies the belief that, ere long, steam- 

 engines may be used upon them between points which would not 

 require, or justify, the construction of regular railroads. A short 

 notice of the most celebrated attempts to adapt steam-carriages to 

 common roads may, therefore, be desirable, accompanied by a few 

 remarks on the characteristic distinctions between the resistances to 

 be overcome in the respective cases of rail, or of common, roads. 



When steam-carriages work upon railroads, they traverse a surface 

 of uniform hardness and rigidity ; and it is easy to distribute the load 

 over a number of carriages drawn by the engine, because the rails 

 maintain the various parts of the train in the desired positions with 

 respect to one another. No difficulty either occurs, in this case, on 

 the score of the guidance of the engine nr of the load ; nor is it neces- 

 sary to provide for avoiding obstacles in the road, or on account of 

 sharp curves or bends. On common roads, however, the yielding 

 nature of the surface imposes a limit to the weight brought upon the 

 driving-wheels ; and the state of the surface as affected by wet, by the 

 addition of fresh metal, or by other accidental causes, must materially 

 increase the irregularity of the resistance. The rates of inclination 

 adopted on common roads, and the small radii of curvature frequently 

 met with upon them, are far more unfavourable than those met with 

 in railways ; and it is found in practice that there are serious objections 

 to the use of more than two carriages in immediate connection with 

 one another on common roads ; so that forcedly the space devoted to 

 the reception of the machinery, boiler, combustible, Ac., is confined 

 within very narrow limits, in order to leave any space available for the 

 conveyance of passengers or of goods. The irregularity of resistance 

 of the road surface renders it necessary also to adopt great precautions 

 in the construction of the parts of the engine designed to transmit 

 motion from the piston-head ; and the constant changes of inclination 

 require that there should be provided, in steam-carriages designed to 

 run on common roads, means for varying at will the amount of power 

 exercised. In all locomotives it is desirable that the machinery should 

 be of the simplest construction, and that it should be susceptible of 

 easy examination and repair; but this is essentially the case with 

 steam-carriages, on account of the variety of action required of them. 

 The consequences of these peculiar conditions are that steam-carriages 

 must be made to combine great power within small compass, and with 

 small dead weights ; they must be constructed so solidly as not to be 

 deranged by the shocks, or the bad state of the roadway ; and lastly, 

 they must be able to work without producing any nuisance, or any 

 interference with the ordinary horse traffic of the public thoroughfares. 

 Hitherto it has not been found possible to secure these conditions, and 

 to secure economy of traction at the same time ; and the substitution 

 of steam for animal power is still confined to railways, notwithstanding 

 the enormous amount of capital they require to be expended on their 

 e< instruct ion. 



It appears that as far back as 1786 attempts were made by William 

 Symington, in Scotland, and Oliver Evans, in Philadelphia, to introduce 

 steam carriages, or waggons, on common roads ; and Mr. Murdoch, the 

 well-known associate of Boulton and Watt, is said in 1782, or 1792, to 

 have made a similar attempt. In 1802, Trevethick and Vivian pro- 

 duced an engine for the same purpose of much greater value than 

 those previously made. After their trial, some years elapsed before 

 other p.utic* took up the question, and it wan not until 1821 that 

 Grillith |>atented his steam-carriage. In 1822 David Gordon began 

 his public essays on the subject, and in the succeeding years he took 

 out several patents connected with it. He was, in 1824, followed 

 by many other inventors, such as Hancock, Summers and Ogle, 

 Dr. Church, Sir J. Anderson, Sir C. Dance, Mr. J. Scott llussell, ftc. 

 The success of these experiments was, as might have been , 

 of a varied character ; but they seem to have roused a singular amount 

 of local opposition, which finally assumed so violent a character as to 

 lead to the nomination of a select committee of the House of Commons 

 to inquire into the " present state and future prospects of land carriage 

 by means of wheeled vehicles propelled by steam or gas on common 

 roads." The report of this committee was published ih October 1831. 

 Although this report w;w favourable to the new application of ft 

 )>ower, and although Mr. Hancock in 1831 produced a steam-carriage 



which, like the one proposed about the same time by Mr. Goldsworthy 

 Giirney, answered to a great extent the anticipations 'of their inventors, 

 the difficulties attending this mode of locomotion were considered to 

 be so great, that about 1832 the conviction in the minds of practical 

 engineers had become almost universal that " every attempt then made 

 to render steam-carriages the means of economical and regular inland 

 communication had totally and absolutely failed." The success of the 

 railway system, then first applied on a large scale, served likewise to turn 

 public attention from the avowedly inferior system of steam locomotion 

 on common roads; and it was not until the recent application of steam- 

 machinery to agricultural purposes had rendered it desirable to intro- 

 duce some mechanical traction-engines of great power, that engineers 

 were again induced to study this particular problem. In the Great 

 Exhibition for 1851 there was only one plan of a locomotive for 

 common roads; but between 1853 and the end of 1860 as many as 

 nine varieties of those engines were submitted to the public, of 

 sufficient importance to merit the attention of the professional journals 

 and occasionally of the various departments of the government. Of 

 these, Boydell's, Clayton's, Bun-ell's, Bray's, Giles's, and Stirling's 

 traction-engines, Lord Caithness's steam-carriage, Aveling's sell | >- 

 pelting agricultural engines, and the engine made by Mr. Creswell I'm- 

 the English and Continental Traction-Engine Company, have attracted 

 the greatest amount of notice, and some of them have actually per- 

 formed good work. Bray's traction-engine, for instance, ha.- 

 usefully employed in our dockyards. Lord Caithness reports that 

 with his-carriage, having' cylinders of 3 inches diameter and 7 inches 

 stroke, he was able to attain on the level a speed of 19 miles an hour, 

 and to ascend inclines of 1 in 7, working at an average expense of from 

 a halfpenny to a penny per mile ; the weight, with water for a run of 

 12 miles, and coals for 20 miles, is only two tons; but the c:i 

 only conveys (in the form represented in the ' Engineer' for O 

 1860) three passengers. Creswell's engine is said on one occasion to 

 have drawn two waggons containing 10 tons of earth each up Pcntonville 

 Hill, a long incline of about 1 in 70 ; but on a repetition of i la- 

 ment it broke down. There seems, therefore, to be some reason for 

 the belief so confidently expressed by Lord Caithness, that ei 

 steam may be substituted for horse-power on common roads ; and 

 as the prejudice against its use has, since 1831, been considerably 

 diminished, the most bitter source of opposition has disappeared. The 

 application of the expansion gear, and the introduction of 

 railways, must however be considered to have effected the greatest 

 service towards the introduction of steam locomotion without the 

 construction of special roadways. With all their modern improve- 

 ments, steam-carriages are nevertheless still but imperfect substitutes for 

 railway travelling, and it may almost be a subject for regret to witness 

 the amount of energy, skill, and money expended upon them. 



The best information on the construction of steam-carriages is to bo 

 found in Gordon's ' Treatise upon Elemental Motion ; ' Hancock's 

 'Narrative;' the 'Mechanics' Magazine;' the 'Engineer;' and the 

 lleports of the Select Committees of the House of Commons in 1831, 

 and 1834 and 1835, upon Steam-Carriages and upon Qoldsworthy 

 Gurney's claims. 



STEAM NAVIGATION. It would seem that navigation, being 

 founded on the bases of geometry and astronomy, would be but one 

 system, practicable alike by the commander of a sailing ship or of a 

 Mcamer ; that practice attained in navigating one class of ves-rls \\uuld 

 be equally available for the safety of the other ; but it is not so. As 

 well may we compare the driving of a spirited horse in a light gig to 

 the driving of a waggon team : there are points of skill in each, and 

 proficiency is also attainable in each, but interchange the drivers, and 

 it is probable that neither of the vehicles would be so well cond n< t > -I 

 as before : and thus it is with steam navigation. The sailor of the 

 old school (for there is specifically a new one), is accustomed to have 

 his eyes aloft ; and the trim of his sails, and the steadying of a bowliiu: 

 here, and the pulling upon a brace there ; the habitual look to wind- 

 ward for coming weather, &c. ; these form the main sources of that 

 unceasing vigilance without which no one can be fit to command. 



The navigation of a ship (in its abstract meaning), is with the sailing 

 eiiniinander a mere routine. A course of measured attentions to 

 certain established customs, handed down from generation to genera 

 tion, and performed at definite periods, leaves his mind, after those 

 periods have passed, nearly free from the duties of calculation alto- 

 gether. But in the new school, things are far different, and it will be 

 useful in this place to illustrate the present state of the subject, by 

 examining into what really constitutes this difference, for it becomes a 

 question of training and qualification. 



We have only to refer to our article COLLISIONS AT SKA, to show 

 that fearful innovations have followed the introduction of steam into 

 our sea services affecting in a high degree the safety of life ; and we 

 also refer to SHIPS and SHIPPING to show what laws are found necessary 

 in preventing such insecurity. Fearful then must be the inn 

 responsibilities of a commander of a steam vessel. Nor does this 

 admit of limitation, for the very causes of all this ar in themselves 

 progressive. 



Very much may be attributed to the increase of speed in steamers ; 

 yet there are other influences which alt'cct steam navigation with 

 peculiar force : among these may be noticed the wide prevailing 

 interest that owners, of steamers in particular, feel in the rapidity of 



