168 



♦ KNOWLEDGE ♦ 



[Feb. 27, 1885. 



I have further applied the same method of charting to 

 the star clouds (using Professor Cleveland Abbe's excellent 

 statistical results* as the basis of my work, finding the 

 clearest and most convincing evidence that the nebuUe 

 form part of our sidereal system. 



I have further charted the stellar proper motions, — the 

 only possible way of recognising any law in these move- 

 ments. Such charts show that many large groups of stars 

 have a common drift, so as manifestly to form separate 

 systems. In the only case where one of these sets of stars 

 has been dealt with by the spectroscopic method for deter- 

 miniog motions of recession and approach, it has been found 

 that (as I specially predicted in that casei) the stars all had 

 a common motion in the direction of sight, as well as 

 athwart that direction. This showed that the evidence 

 given by charts of proper motions is trustworthy. 



But this is the merest begiuning. We want surveys of 

 the heavens made with many other powers, — as with a fl- 

 inch telescope ; a iinch telescope (this I have partly tried, 

 and I know the results of a full survey would be most 

 valuable); with a 6-inch telescope; and with a 12iiich 

 telescope : the more interesting regions disclosed by such 

 surveys as these being then examined with the highest 

 telescopic powers that can be brought to bear upon them. 

 It is essential that the southern hemisphere should be at 

 least as carefully surveyed as the northern ; for no one who 

 has ever looked at the southern skies can fail to recognise 

 that they are much more variegated, and therefore much 

 more likely to be instructive in regard to celestial architec- 

 ture, than the skies north of the equator. 



Lastly, these surveys should be accompanied by widely 

 extended study of proper motions ; by the application of 

 the spectroscope to determiue the constitution of stars in 

 ditl'erent parts of the heavens, and their movements of 

 recession and of approach. 



I venture to predict that as this work proceed?, for I am 

 sure it will in due time be undertaken, science will be com- 

 pelled to give up more and more the idea of uniformity of 

 structure within the stellar universe, recognising a grandeur 

 and complexity iu its architecture, a variety yet harmony in 

 its movements, and a signi6cance in its amazing vitality, 

 akin to but of a far higher order than the corresponding 

 qualities within the planetary ^ystetll. 



THE ELECTRIC LTGHT OX THE 



BRIGHTON RAILWAY. 



By W. Sling 0. 



AMIDST the many inconveniences that aiirait the 

 average railway traveller, there is, to my mind, 

 not one that is more trjing or vexatious than to be com- 

 pelled to sit out a long journey in a carriage illuminated (!) 

 by the old, dirty, smoky oil-lamp. Nevertheless, until very 

 recently, this is what one and all had to do who=e business 

 or pleasure involved them in a railway journey at a time 

 when sublight was absent : and even now we are ofiener 

 than not compelled to undergo the same torjiieut. 



The introduction of the Piatsch Gas system wrought a 

 revolution on a small scale. Our underground railway 

 trains are fitted under it, and it has found sujiport in a few 

 other directions. But the greatest result, perhaps, which 

 has been brought about by even a limited application of 



* I had already charted the nebulae on a less complete plan 

 before Prof. Abbe had obtained those results. 



t The group of stars /?, y, ^, i, and ? of the Great Bear, with S's 

 small companion, Alcor, called in country parts of England "Jack 

 by the Middle Horse." 



the system is that it has shown the public that a light 

 superior to that given by oil is practicable ; and, were 

 nothing eLe available, the railway companies would, sooner 

 or later, be compelled by force of public opinion to adopt it. 



There is, however, something which is superior to gas 

 even in a railway carriage, and that something is electricity. 

 We certainly owe it to the]]emLnently able and enterprising 

 management of the London, Brighton, and South Coast 

 Railway that electricity, as an illuminating agent in rail- 

 way carriages, has been proved ; for the first experiments 

 in this direction were made by that company some three 

 years ago, when the PuUman express, which runs daily 

 between the Victoria and Brighton stations, was lighted by 

 electricity. In that case accumulators of the Faure type — 

 some of the very first brought into England — were em- 

 ployed. 



They were charged overnight at Victoria by means of a 

 dynamo worked by a gas-engine (wires being led from 

 the shed to the brake-van), and supplied throughout the day 

 sufficient current to illuminate the twenty-eight lamps fitted 

 in the various carriages composing the train which per- 

 formed the journey from Loudon to Brighton and back 

 twice daily. 



The advantages of the system over the previously-em- 

 ployed oil-lamps were, it is almost needless to say, too real 

 and too apparent not to secure at once the admiration and 

 gratification of the patrons of the line. The light was 

 steady, clear, and only showed itself when wanted. 



Illumination by oil or gas means that in the day-time, 

 if the train has to run a fifty-mile or even longer journey, 

 and has one or two short tunnels to traverse, the lamps 

 must all be burning through the entire length of the 

 journey on account of the tunnels. 



With the electric light this is not the case. The guard 

 is provided with a simple switch, by turning which he is 

 able to send the current into the lamps on approaching a 

 tunnel, and to stop the current on emerging from the tunnel. 

 Here, then, is a very decided advantage in favour of 

 electricity. 



The train thus fitted has continued its daily journeys 

 since the inauguration of the system, but there were 

 soon discovered many features in coanection with it that 

 required modification before it could become the com.- 

 mercial success that was hoped for it. In the first place, 

 there was the expense of the gas-engine and its attendant. 

 This is a serious objection, to say nothing of the allowance 

 that ought to be made for renting the engine-house. It may, 

 however, be observed that, were the system extended to 

 several trains instead of a single one, so as to divide the 

 engine and accessory expenses between them, the cost per 

 train would obviously be considerably reduced. 



In the following year a new system was introduced, and 

 employed on the London-bridge and Brighton express, and 

 on a local train running between Victoria, Crystal Palace, 

 and London-bridge, ic. It had been worked out by Mr. 

 Stroudley, the talented engineer to the company, and Mr. 

 Houghton, its energetic telegraph superintendent. In this 

 system the engine was discarded entirely, and the dynamo 

 was fixed in the brake-van, and worked from a counter- 

 shaft geared on to one of the axles. While the train 

 travels at a sufficieutly-rapid rate, it is easy to see 

 that the dynamo might be driven fast enough to feed 

 the lamps. But whence is the electricity to come 

 neoessary to illuminate the lamps when the train is 

 travelling slowly or when it is standing still ? This is 

 accomplished in a very simple manner. While the train is 

 running rapidly, electricity may be generated, whether the 

 light is wanted or not. Consequently, the dynamo, B C, is 

 permanently connected to a set of twenty accumulators, X P. 



