Sept. lo, 1874] 



NATURE 



391 



creased ; and each of these entails some attendant dangers. As 

 a natural consequence of the increased traffic on old railways, the 

 additional traffic on new lines, and the increased complexity of 

 the railway system as a whole, there have been during recent 

 years more numerous accidents than in the earlier times of 

 railways. It is to be recollected, however, that with a greater 

 number of people travelling daily, more numerous accidents 

 might be expected, and that their increased frequency, en the 

 whole, does not necessarily indicate increased danger to the 

 individual traveller. Referring to (he statistics of railway 

 accidents published by the Board of Trade in Capt. Tyler's 

 Report for the year 1S73, I find, for various periods during the 

 last twenty-seven years, throughout the United Kingdom, the 

 proportion of passengers killed from all causes beyond their own 

 control, to the number of passengers carried, to have been, in 

 round numbers : — 



Proportion of number killed to number carried 



in the three years 1847, 1S4S, and 1849, I in 4,782,000 



In the four years, 1S56, 57, 58, and 59 . I in 8,708,000 



In the four years, 1S66, 67, 68, and 69 . i in 12,941,000 



In the three years, 1870, 71, and 72 . . I in 11,124,000 



And in the single year 1873 .... I in 11,381,000 



It is thus gratifying to observe, that in spite of the increased 



risks naturally tending to arise through the increased and more 



crowded trallic and the more complicated connections of lines, 



the danger to the individual traveller is now less than half what 



it was 26 years ago ; at least this result is indicated, in so far as 



we can judge, from the statistics of deaths of passengers from 



causes beyond their own control. That the conducting of the 



traffic of railways still involves hazards far from inconsiderable, 



and that we have much to wish for towards abatement of 



dangers of numerous kinds, is proved by the fact that during 



the single year 1S73 there have been killed of the officers and 



servants of the railway companies in the United Kingdom, i out 



of every 323 : so that, at this rate, extended through a period of, 



for example, 20 years' service, there would be I out of every 16 



of the officers and servants killed. 



These deaths o( officers and servants are not to be .supposed 

 to be caused in any large proportion by collisions, and by other 

 accidents to trains in rapid motion. The great majority of 

 them arise in shunting and other operations at stations and 

 along the lines, and occur in numerous ways not beyond the 

 control of the individuals themselves. In respect to the passen- 

 gers, too, it ought to be known and distinctly recollected, that 

 although collisions and other violent accidents to trains in rapid 

 motion, together with other accidents beyond the control of the 

 individuals, usually cause by far the deepest impression on the 

 public mind ; yet the numbers of these fatal accidents are small 

 in comparison with others arising to passengers Irom causes more 

 or less within their own control. For instance, it may be noticed 

 that in last year, the year 1873, while the deaths ol passengers 

 arising from all causes beyond their own control, in the United 

 Kingdom, were only 40 in number, there were four times as many 

 killed, namely 160, in other ways; and of these there were as 

 many as 62 killed in the simple way of their falling between 

 carriages and platforms. 



In "respect to the conducting of the traffic of the trains in 

 motion, it appears to me, on the whole, that when we consider 

 the vast complexity of the operations involved in working many 

 of our ramified and crowded railways, and when we consider the 

 indefinitely numerous things which must individually be in proper 

 order for their duty, and must be properly woiked in due 

 harmony by men far away from one another, some stationed on 

 the land, and others rushing along on the engines or trains, the 

 wonder is, not that we should have numerous accidents, but that 

 accidents should not be of far more frequent occurrence. There 

 can be, no doubt, however, but that of the accidents which do 

 occur, many arise from causes of kmds more or le.^s preven- 

 tible according lo the greater or less degree in which due pre- 

 cautions may be adopted. 



Gradually, during a period of 20 or 30 years past, a very fine 

 system of watching, signalbng, and otherwise arranging lor the 

 safety of trains, has been contrived and very generally introduced 

 along our principal lines of railway. In saying this, I allude 

 ihietly to tiie block system of working railways, witli the aid of 

 telegraphic sign.als and interlocking mechanisms lor the working 

 ol the points and signals. 



In former times it was customary to allow a cerLiin number 

 of minutes to elapse after a train passed any station, or junction, 

 or level crossing, or other point where a servant of the ccmpany 



was stationed, before the succeeding train was allowed to pass 

 the same place. Thus, at numerous points along the line a 

 time interval was preserved between successive trains. It was 

 quite possible, however, that the foremost of the two trains, 

 after passing any of these places where signals were given, 

 might become disabled, or might otherwise be made to go 

 slowly, and that the following train might overtake it, and come 

 into violent collision with it from behind. In order to provide 

 against the occurrence of such accidents, a system was introduced 

 called the Block Syston ; and its main principle consists in 

 dividing ihe line into suitable lengths, each of which is called a 

 /'/ofi sa/ioii, and allowing no engine or train to enter a block 

 section until the previous engine or train has quitted that portion 

 of the line. In this way a space interval of at least the length of 

 a block section is preserved between the two trains at the 

 moment of the later train's passing each place for signalling, 

 and the risk of this Sf ace interval becoming dangerously small by 

 negligence or other accidental circumstances, as the later train 

 approaches the next place for signalling, is almost entirely 

 avoided. 



P'urthcr, at each signalling station, the various levers or 

 handles for working the points, and those for working the sema- 

 phore signals for guiding the engine-drivers, instead of being, as 

 was formerly the case, scattered about in various situations 

 adjacent to the signalling station, and worked often, some by one 

 man and some by another, without sufficient mutual under- 

 standing and without due h.armony of action, are now usually all 

 brought together into one apartment called the signal cabin. 

 This cabin, like a walch-tower, is usually ele\ated considerably 

 above the ground, and is formed with ample windows or glass 

 sides, so as to afford good views of the railway to the man who 

 works the Itveis for the semaphores and points, and who 

 transmits, by electricity, signals to the next cabins on both sides 

 of his own, and, when necessary, to other stations along the line 

 of railway. 



The interlocking of the mechanisms for working the points 

 and for working the semaphores which, by the signals they 

 show, control the engine-drivets, consists in having the levels 

 by which the pointsman works these points and signals, so con- 

 nected that the man in charge cannot, or scarcely can, put one 

 into a position that would endanger a train, without his having 

 previously the necessary danger signal or signals standing so as 

 to warn the engine-driver against approaching too near to the 

 place of danger. 



The latest important step in the development and application 

 of the block system is one which has just now been made in 

 Scotland, on the Caledonian Railway. Before explaining its 

 principle, I have first to mention that a semaphore arm raised to 

 the horizontal position is the established danger-signal, or signal 

 or debarring an engine-driver from going past the place where 

 the signal is given. Now, the ordinary practice has been, and 

 still is, to keep the semaphore arm down from that levil 

 position, and so to leave the line open for trains to pass, except 

 when the line is blocked by a train or other source of danger 

 on the block section in front of that semaphore, and only to 

 raise the semaphore arm exceptionally as a signal of danger in 

 front. The new change, or improvement, now made on the 

 Caledonian Railway consists mainly in arranging th.at along a 

 line of railway the semaphore arms are to be regularly and 

 ordinarily kept up in the horizontal position for prohibiting the 

 passage of any train, and that each is only to be put down when 

 an approaching train is, by an electric signal from the cabin 

 behind, announced to the man in charge of that semaphore, as 

 having entered on the block section behind, and when, further, 

 that man has, by an electrical signal sent forward to the next 

 cabin in advance, inquired whether Ihe section in advance of his 

 own cabin is clear, and has received in return an electrical signal 

 meaning " T/ie litw is clear: you may put thm'ii your debarritig 

 iignal, aiul let the train pass your cabin!' The main effect of 

 this is, that along a line of railway the signals are to beregularjy 

 and ordinarily standing up in the debarring position against 

 allowing any train to pass ; but that just as each train ap- 

 proaches, and usually before it has come in sight, they go down 

 almost as if by magic, and so open the way in front of the train, 

 if the line is ascertained to be duly safe in front ; and that 

 immediately on the passage of the train they go up again, and 

 by remaining up keep the ro.id closed against any engine or 

 train whose approach has not been duly^announced in advance 

 so as to be known at the fiist and second cabins in front of it, 

 and kept closed, unless the entire block section between those 

 two cabins is known to have been left clear by the last preceding 



