i86 



NATURE 



[June 25, 1903 



to such an extent as might tend to arrest advancement in 

 type or design, although it was of the utmost importance 

 that uniformity should be arrived at with regard to the 

 loads to which such structures might be subjected. In the 

 discussion it was suggested that loads on bridges were 

 nearing a limit, as electric traction would probably come 

 into use, and this would do away with the need for the 

 heavy steam locomotive. 



In a contribution on " The Design of Permanent Way 

 and Locomotives for High Speeds," by Mr. J. C. Inglis, 

 it was pointed out that the increase in train mileage of 

 British railways was mostly on long distance traffic, which 

 meant heavy trains with heavy axle loads hauled at a 

 relatively high speed. For express running, up to 60 miles 

 an hour, no curves should be less than 40 chains radius. 

 Heavy rails gave smoother running, and 90 to 100 lbs. per 

 yard was often the practice. Four-coupled engines, with 

 the front wheels coupled and a bogie under the foot-plate, 

 formed an undesirable class of engine for high speed 

 running, whilst engines with single drivers, and only one 

 axle in front and one behind, were likewise unsatisfactory, 

 and plunged considerably, even on good roads. Equalising 

 levers had much to recommend them, and recent practice 

 had been in the direction of raising the centre of gravity 

 of the locomotive. 



Mr. W. J. Cudworth read an interesting paper on 

 " Automatic Signalling," giving particulars of applications 

 that had been made on the London and South-Western Rail- 

 way and on the North-Eastern Railway. Mr. Jacomb- 

 Hood, in the discussion, said he was convinced that auto- 

 matic signalling had a great future before it. 



Lieut. -Colonel Yorke, R.E., introduced the subject of 

 " The Organisation and Administration of an American 

 Railway," which he dealt with in some detail. He advo- 

 cated the separation of the traffic or commercial depart- 

 ment from the operating or working department, as 

 followed in America, although unusual in this country. 

 The value of keeping accurate statistics was dwelt upon 

 during the discussion. 



" The Relative Advantages of Overhead, Deep-level, and 

 Shallow Subway Lines for the Accommodation of Urban 

 Railway Traffic " was the subject brought forward by Mr. 

 S. B. Cottrell, who discussed the respective advantages and 

 disadvantages of the different systems. 



Harbours, Docks, and Canals. 



This section met on the first and last days of the congress, 

 Wednesday and Friday, and five papers were read in all. 

 The first paper was on " Dredging in New South Wales," 

 Mr. C. W. Harley being the author. He pointed out that 

 rivers were the natural means for conveying produce, and 

 the New South Wales Government had expe.ided consider- 

 able sums on improving its navigation. Particulars of 

 the extensive plant that was used for this purpose were 

 given. 



The second paper on the "list was "Dredging, with 

 Special Reference to Rotary Cutters," by Mr. J. H. Apjohn. 

 The value of hydraulic dredgers, and the results achieved 

 on the bar of the Mersey and other rivers, were first referred 

 to. In dealing with rotary cutters, the author pointed out 

 that the form of the blades and the angle at which they 

 were_ set, whether they were straight or spiral, and the 

 openings between them at the bottom, were the points to 

 be determined. Different descriptions of material needed 

 different forms of cutters. These two papers were discussed 

 together, Sir Leader Williams, Prof. Vernon Harcourt, Mr. 

 Wheeler, Mr. Matthews, and others speaking. The 

 question of " Foreshore Protection and Travel of Beaches " 

 was next taken, the subject being introduced by Mr. W. T. 

 Douglass. This matter was discussed at a conference at 

 Norwich, held last January, and the author dealt with the 

 various points raised in connection with the subject, such 

 as direction of current, depth of water, effect of flood tides 

 on the travel of the beach, angle and length of groynes, 

 &c. In the course of discussion, Mr. Matthews pointed 

 out that often the value of land reclaimed was not equal 

 to the cost of saving it. 



The other papers read in this section were " The Modern 

 Equipment of Docks, with Special Reference to Hydraulic 

 and Electric Appliances," by Mr. Walter Pitt; and " Recent 



NO. 1756, VOL. 68] 



Improvements in Canal Engineering," by Mr. Gerald 

 FitzGibbon. 



Machinery. 



In the machinery section sittings were held on the 

 Wednesday and Thursday. The first subject was intro- 

 duced by Mr. Archd. P. Head, and was on " The Speed of 

 Overhead and other Cranes as a Factor in the Economic 

 Handling of Material in Working." The author favoured 

 continuous current for crane work at 220 to 500 volts. He 

 preferred this to alternate current on account of the greater 

 starting torque and acceleration which it gave ; although 

 alternating current motors were efficient at full loads, they 

 could only have a strong starting torque at the expense of 

 efficiency. Continuous current also admitted of easier 

 regulation, was cheaper in wiring, and could be stored in 

 batteries to equalise a variable load. Series-wound motors 

 automatically ran faster with lighter loads, and should be 

 used coupled permanently to the gear. They could with- 

 stand 100 per cent, overload for short periods, and higher 

 overloads momentarily, without damage. Motors running 

 continuously with clutch connections to the gearing should 

 be shunt-wound. Quick stopping could be achieved by an. 

 electric brake working on the armature shaft, operated by 

 a weight or spring, and taken off by a solenoid in series 

 with the motor. \ som-jwhat lively discussion followed the 

 reading of Mr. Head's paper, Mr. Tannett Walker and 

 Mr. Ellington advocating the use of hydraulic cranes,, 

 although the latter allowed that electricity was the best 

 source of motive power for overhead travellers. 



A valuable paper by Mr. H. J. Marshall, " Gauges and 

 Standards as Affecting Shop and Manufactory Administra- 

 tion," followed. The subject is one which does not well 

 lend itself to being abstracted in a few words, but Mr.^ 

 Marshall's paper is the more valuable because it represents' 

 actual experience in large works. 



Mr. H. A. Humphrey's paper on " Internal Combustion 

 Engines for Driving Dynamos " was also one of consider- 

 able interest, and attracted a good many of the electrical 

 engineers from section vii. The author dealt with the 

 large gas-engines which have quite recently come into use, 

 and the design of which, unfortunately, we largely owe to 

 the Continent, where the application of blast furnace gas 

 to internal combustion engines has given an impetus to 

 this branch of industry. The author stated that there were 

 about fifty firms manufacturing large gas engines of 200 

 horse-power and upwards. The engines completed or on 

 order numbered 515, having an aggregate capacity of 

 328,065 horse-power ; of these, 398 engines were for 

 dynamos, and gave collectively 206,805 I.H.P. The gas 

 producer and gas engine constituted the cheapest means 

 of generating electric power, where coal was the basis of 

 energy, and the gas engine had proved quite trustworthy 

 for driving alternators in parallel. He considered that 

 ultimately the gas engine would entirely take the place of 

 steam plant in large central electric stations. A long 

 discussion followed the reading of this paper, in which the 

 views of the author were upheld by some speakers. Dr. 

 Kennedy (who occupied the chair), however, said that be- 

 fore he advised the application of internal combustion 

 engines for the generation of electrical energy he would 

 like to feel more confidence, or have more experience on 

 the subject. Mr. Crossley and Dr. Hopkinson, who both 

 spoke, gave some remarkable figures, showing the advan- 

 tage of gas engines over steam engines in regard to 

 economy. 



" The Use of Petrol Motors for Locomotion " was the 

 subject introduced by M. E. Sauvage, the well-known 

 French locomotive engineer, who gave in detail the points 

 that should be observed in designing a successful petrol 

 motor. In the discussion, Mr. Aspinall and other loco- 

 motive engineers pointed out that though the single unit 

 vehicle had advantages, and appeared very attractive at 

 first sight, practical considerations militated against it, 

 and where, in the past, the system had been tried, it had 

 been abandoned sooner or later. 



The chief feature in this section was the last paper read, 

 which was on " Apprenticeship in Engineering Education," 

 by Prof. J. D. Cormack. The subject is too long and too 

 important to treat in a brief report of this nature. Prof. 

 Cormack merely set forth the chief aspects of the question, 

 without pretending to arrive at any conclusion. 



