Septemuf.k 24, 1896J 



NA TURE 



511 



The hydraulic power used in the docks is very large, the 

 indicated horse-power of the engines amounting to 1673 in the 

 case of Liverpool, and 874 in that of Birkenhead ; whilst the 

 Hydraulic Power Company are supplying some 1000 h.p. to 

 railways and private firms. 



The direct-acting hydraulic lifts of the Mersey Railway have 

 now^ been at work for ten years, and through these, at St. James's 

 Station, no le.ss than 75,000,000 to 80,000,000 of passengers have 

 passed with regularity and safety. 



It is remarkable that, whilst C'lreat Britain led the van in the 

 introduction of steam locomotion, she has lagged in the rear as 

 regards electric and other mechanical traction. This arose in the 

 first instance from mistaken legislation, which strangled electrical 

 enterjirise, w-hich is still much hampered by the reluctance of 

 public authorities to permit the introduction of the necessary 

 poles and wires into towns. 



At the date of the latest published returns there were at work 

 in the United States no le.ss than 12,133 miles of electric, in 

 adilitiun 10 599 miles of cable, tramway. Hardly a large village 

 l)Ul has its installation, and vast have been the advantages 

 lierived from these facilities. In Brooklyn one company alone 

 owns and works 260 miles of overhead trolley lines. With the 

 exception of some small tramways at Portrush, Brighton, Black- 

 pool, South Stafibrdshire, Hartlepool, &c. , the only examples in 

 this country of serious attempts to apply electro-motive force to 

 the carriage of passengers are the City and South London Rail- 

 way and the Liverpool Overhead Railway, the latter being the 

 latest constructed, and having, therefore, benefited by the ex- 

 perience gained upon the London line. 



This railway is over six miles long, a double line of the normal, 

 or 4 ft. S^ in. gauge, running on an iron viaduct for the whole 

 length of the docks ; the installation is placed for convenience of 

 coal supply about one-third of the distance from the northern 

 end. Particulars of this interesting work will be placed before 

 the Section, but suffice it to say that a train service of three 

 minutes each way' is readily maintained, with trains carrying 112 

 passengers each, at an average speed (jf twelve miles per hour, 

 including stoppages at fourteen intermediate stations. During 

 the last year, as before stated, 1\ million passengers were carried, 

 the cost of traction per train mile being 'i,'^d. 



The Hartlepool Tramway is proving successful, overhead 

 trollies and electric traction having taken the place of a horse 

 tramroad, which was a failure from a traffic ]5oint of view. 



Careful researches are being prosecuted, and experiments 

 made, witli the intention of reducing the excessive weight of 

 storage l)atteries. If this can be effected, they should prove 

 very efficient auxiliaries, especially \shere, in pas.sing through 

 towns, underground conductors are dangerous, and overhead 

 wires objectionable. 



In connection with electric traction, it is very important to 

 reduce, if possible, the initial force required for starting from 

 rest. Whether this will be best attained by the improvement of 

 bearings and their better lubrication, or by the storage, for 

 starting ]3urposes, of a portion at least of the force absorbed Ijy 

 the brakes, remains to be seen, but it is a fruitful field for 

 research and experiment. 



In the United States there is a very general and rapid dis- 

 placement of the cable tramways by the overhead wire electric 

 system. The latter has many opponents, owing, probably, to 

 causes which are preventible. 



Many accidents were caused l)y the adoption of very high 

 tension currents, which, on the breakage of a wire, were uncon- 

 trollable, producing lamentalile results. 



The overhead wires were placed in the middle of the street, 

 causing interference with the passage of fire-e.scapes. 



The speed of the cars was excessive, resulting in many persons 

 lieing run over. 



The cable system, therefore, found many advocates, but the 

 result of experience is in fiwour of electrical traction under 

 proper safeguards. 



The cable system can only compete with the electric system 

 when a three-minute or quicker service is possible, or, say, 

 when the receipts average ^20 per mile per day ; it is impos- 

 sible to make up lost time in ruiniing, and the cars cannot be 

 " backed." If anything goes wrong with the cable the whole 

 of the traffic is disorganised. The cost of installation is much 

 greater than in the case of electricity, and extensions are 

 difficult. 



On the other hand, electricity lends itself to the demands of a 

 growing ilistrict, and extensions are easily effected ; it satisfies 



NO. 1404, VOL. 54] 



more easily the growing demands on the part of the public for 

 luxury in service and car ajipointment. It is less expensive in 

 installation, and works with greater economy. By placing the 

 wire at the side of the street, and using a current of low voltage, 

 the objections are greatly minimised, and the cars are much more 

 easily controlled and manipulated. In cases of breakdown these 

 are limited to the half-mile section, and do not completely dis- 

 organise the service. Electric cars have been worked success- 

 fully on gradients of i in 7. 



The conduit slot system can be adopted with good results, 

 provided care is taken in the design of the conduit, and allow- 

 ance made for ample depth and clearance ; a w idlh of ^-inch is 

 now proved to be sufficient. Where, however, there are frequent 

 turnouts, junctions, and intersecting lines, the difficulties are 

 great, and the cost excessive. 



The following figures represent the cost of a tramway, on this 

 system, in America. 



Cost of track and conduit ^5600 (per mile of 



Insulator, boxer, and double conductor . 480 single track) 

 Asphalte paving on 6 inches of concrete 



to 2 feet outside double track) . . 1500 ,, 



^7580 

 Complete cost of operating 4 miles of double track for 24 hours 

 per day with 24 minute service, 4'55(f. per train mile (ex- 

 clusive of interest, taxes, &c. ). 

 One train consists of one motor car and one trailer. 

 The trains make a "round trip of eight miles in one h(,ur, with 

 three minutes lay-oft" at each end. 



The cost of keeping the slot clean comes to about 40/. per 

 quarter, and the repairs to each plough conductor about 50.r. per 

 quarter. 



Attempts have been made to obviate the necessity of the slot 

 by w hat is know-n as the closed conduit ; but at present the 

 results are not encouraging. 



The following figures will help to convey to the mind the 

 great development which is taking place in America, as regards 

 the earnings upon lines electrically equipped. They are derived 

 from the Report of the State Board of Railroad Commissioners 

 for Massachusetts. 



Increase 

 1S8S. 1894. per cent. 



Net earnings per passenger carried ... '48 78 62 "5 



Net earning per car mile ... ... 278 4*83 73 '5^ 



Net earning per mile of road ... ... .1^484 .^762 57 



In addition to the application of electricity fijr illuminating 

 purposes, and for the driving of tram-cars and railways, it has 

 also been applied successfully to the driving of machinery, cranes, 

 lifts, tools, pumps, &c., in large factories and works. This has 

 jjroved of the greatest convenience, abolishing as it does the 

 shafting of factories, and applying to each machine the necessary 

 power by its own separate motor ; the economy resulting from 

 this can hardly be over-estimated. 



It is also successfully employed in the refining of cop]ier, and 

 in the manufacture of phosphorus, aluminium, and other metals, 

 which, before its application, were beyond the reach of 

 commercial application. 



The extent of its development of chemical purposes in the 

 future no one can foresee. 



It is hardly necessary to call attention to the successful manner 

 in which the Falls of Niagara, and the large Falls of Switzer- 

 land, and elsewhere, are being harnessed and controlled for the 

 use of man, and in which horse-power by thousands is being 

 obtained. 



At Niagara, single units of electrical plant are installed equal 

 to about 5000 horse-power output. The units are destined to be 

 utilised for any of the purposes previously suggested, and it is 

 computed that one horse-power can be obtained from the river, 

 and sold for the entire year day and night continuously, for the 

 sum of 3/. 2s. dd. per annum. 



Electric head lights are being adopted for locomotives in the 

 United States. 



The use of compressed air and compressed gas for tractive 

 purposes is at present in an experimental stage in this country. 

 The latter is claimed to be the cheapest for tramway purposes, 

 the figures given being — 



Single horse cars ... ... ••• ••• •■• S?"- 



Electrical cars, with overhead wires a,\d. 



Gas cars ... ... ••• ••• ••• •■• Si"- 



