October 17, 1901] 



NA TURE 



61 



since the engineering departments of the Glasgow International 

 Exhibition would naturally be frequently visited by members of 

 the Section, it was arranged to have a paper descriptive of the 

 mechanical exhibits ; this was given by Mr. D. H. Slorton, and 

 proved most useful in assisting visitors to spend to the best 

 advantage the hours they gave up to the Exhibition. The 

 author, rightly enough, deplored the almost complete absence of 

 any marine engineering exhibits and the poor show of locomo- 

 tives ; but he pointed out that in another of the great industries 

 of Glasgow, steel making, there was a remarkably complete and 

 most instructive series of exhibits, the enormous steel plates and 

 huge steel forgings and castings being especially interesting. On 

 the same day two interesting papers by Mr. J- R. Wigham, on 

 a long-continuous-burning petroleum lamp for beacons and 

 buoys, and on a new scintillating lighthouse light, were also 

 read. In the first paper the author claimed that by burning 

 petroleum and using the wick horizontally, so that the flame 

 sprang from the side and not from the edge or ends, a steady 

 light could be secured requiring no attention for a month ; the 

 slow continuous movement of the wick over the roller was secured 

 by an ingenious arrangement in which the gradual escape of oil 

 from a cylinder caused a float attached to the wick end to 

 slowly descend, thus causing the wick to travel over the roller 

 and so present a new surface to the flame. Examples of both 

 these appliances were on show in the University buildings. 



Another paper on this day was a short note by Mr. J. E. 

 Petavel, in which he described a recording manometer he had 

 devised, for obtaining a record of the high pressures reached by 

 exploding charges of gas in closed cylinders. The instrument 

 seemed well adapted lor its purpose and ought to prove useful 

 in gas and petroleum engine work. 



Two reports were presented to the Section, one by the 

 Small Screw Gauge Committee, in which the extreme trouble 

 they had met with in obtaining accurate gauges w-as again de- 

 scribed, and as a result practically little progress had been made 

 since the last report was presented at Bradford ; the other by 

 the Committee on Resistance of Road Vehicles to Traction. 

 This committee, which was appointed at Bradford, has dis- 

 covered that the task it has embarked upon is a most difficult 

 one, and one which will involve an expenditure far beyond any 

 grants which could be given by the Association. The committee 

 therefore sought and obtained authority to approach other bodies 

 for financial help — many promises of substantial assistance had 

 been given before the meeting. The work done up to date is 

 briefly as follows: — (a) a dynamometer has been designed and is 

 in course of construction ; {b) a motor (lent by a member of the 

 committee) is being fitted up to carry the dynamometer and is 

 having a new and more powerful engine fitted to it ; [c) it has 

 been decided after careful consideration to begin the experiments 

 by testing single wheels with various types of tyres, on artificial 

 tracks, and then later on, with the experience gained in these 

 preliminary investigations, the work on actual vehicles on 

 ordinary roads will probably be much simplified. As some 

 misapprehension exists as to the work the committee are 

 attempting to carry out, it may be as well to state that it is 

 work of the utmost value to the country, and work of a highly 

 scientific character. No recent experiments have been carried 

 out on this most important question, and designers of motor 

 vehicles are obliged either to adopt rule of thumb methods or 

 to fall back on data obtained by experiments made many years 

 ago, on roads of quite dififerent construction to those now in use, 

 and with only one type of tyre, the solid steel or iron one. 

 Should the committee succeed in the elaborate series of experi- 

 ments they have planned, not only will designers of self- 

 propelled vehicles have constants and data available for their use, 

 upon which they can place absolute reliance, but road engineers 

 will have exact information on two questions tif the greatest 

 interest to them, the effect of the method of moving a vehicle 

 (that is, whether hauled of self-propelled) upon the life of a 

 road, and secondly, the relative advantages of the different 

 materials now in use for road making in regard to the frictional 

 resistances encountered by the vehicles moving over them. 



As the president of the Section devoted a part of his address 

 to the modern development of passenger and goods traffic, it 

 was natural that many of the papers read before the Section 

 should deal directly or indirectly with this subject. Mr. N. D. 

 ^[acdonald, in a paper on railway rolling stock present and 

 future, attacked in vigorous fashion railway management in 

 this country ; he undoubtedly put his finger on many weak spots, 

 notably as regards brakes and our old-fashioned goods trucks, but, 



NO. 1668, VOL. 64I 



like most amateurs when dealing with professional subjects, he 

 spoilt much of his case by exaggeration. Professional engineers, 

 like every other class of men, are liable to errors. They are 

 prone to prefer old-fashioned methods and ate too little inclined 

 to take up and try novelties, but, after all, they are men of 

 understanding and business men, and they are not likely to 

 shut their eyes to improvements going on in other countries or 

 to refuse to adopt them simply because foreigners first tried 

 them. No one who travels much can fail to note the great im- 

 provements in railway management in this country during the 

 past ten years, or the many changes still to be made if we are 

 to keep abreast of the latest advances ; but, after all, it is wiser 

 to adopt radical changes cautiously, and we fancy the public 

 will continue i to place more reliance on the judgment of the 

 trained expert than of the over-eager amateur. 



Mr. Bunau-Varilla, formerly engineer-inchief of the Panama 

 Canal, in a paper on the canal, vigorously defended the 

 judgment of those who selected that site for the canal 

 instead of the Nicaragua route. The author gave many strong 

 reasons for his preference for Panama : in particular he con- 

 trasted the almost entire freedom of the Panama site from 

 seismic disturbances with the constant and ever. present danger 

 to all concrete and masonry work all along the Nicaragua 

 route from such causes. The case for Panama was so strongly 

 put that it was unfortunate there was no real discussion on the 

 paper, and therefore the arguments in favour of Nicaragua were 

 not given a chance. 



In electrical engineering, only two papers of much interest 

 were presented, a valuable one by Prof. E. Wilson, on the 

 conmiercial importance of aluminium, and a paper by Mr. 

 Killingworth Hedges, on the protection of buildings from light- 

 ning. Prof. Wilson, after a brief description of the latest 

 methods of manufacture, devoted himself mainly to an account 

 of the use of aluminium as a conductor of electricity and its 

 advantages for this purpose. In the discussion, the president 

 (Colonel Crompton) referred to the great difficulty in securing 

 uniform quality in aluminium tubes and sheets, and suggested 

 that this stumbling-block must be removed if the extended uses 

 of the metal which engineers hoped for were to become possible. 

 Mr. K. Hedges drew attention to the work of the committee 

 of British architects which was now engaged in con- 

 sidering the question of the protection of buildings from 

 lightning effects, and to the urgent need of the adoption 

 of some uniform system. He described in detail his 

 re-arrangement of the system in use at St. Paul's Cathedral 

 in London, where the conductors put up in 1872 were found 

 to be quite useless for the purpose they were intended to 

 serve. He had increased the number of ordinary conductors 

 from air to earth, and, in addition, ran horizontal cables on the 

 ridges of the roofs and in other prominent positions, thus en- 

 circling the building. These were connected to the vertical 

 conductors wherever they crossed, and were also furnished at 

 intervals with aigrettes or spikes, invisible from the ground 

 level, thus giving many points of discharge. The author 

 drew attention to the unsuitability of soldered joints for con- 

 ductors, and described his own special joint box ; he also ex- 

 plained the tubular earth he designed to get over the difficulties 

 brought about by the old foundations of the cathedral interfer- 

 ing with the use of an ordinary earth plate. In the more purely 

 mechanical side of its work, the Section dealt with two papers 

 of much interest. Prof. George Forbes described his " folding 

 rangefinder for infantry," and iNIr. JI. Barr the machines he 

 had designed for the manufacture of type. Prof. Forbes' in- 

 strument is of the class known as "one-man portable-base 

 range-finders," and possesses great accuracy up to a range 

 of 3000 yards. It was founded on Adie's original 

 instrument. It consists of a folding aluminium base of square 

 tube, hinged at the centre, and a field glass. At each end of 

 the base when opened out is a doubly reflecting prism, the rays 

 of light from any object are reflected at each of these end prisms 

 along each half tube, and then again at the centre into the two 

 telescopes of thejiinocular glass, the final directions of the rays 

 being parallel to the original. The angle between these rays 

 is measured by means of two vertical wires, one in each tele- 

 scope, one wire is fixed, and the other can be moved by a micro- 

 meter screw until the two appear to coincide and the object 

 appears distinctly ; the distance of the object is then at once 

 given, to within 2 per cent, in 3000 yards. The author claimed 

 gre it accuracy in stereoscopic vision, but Profs. Barr and Stroud, 

 who took part in the discussion, and drew attention to the 



