October i8, 1900] 



NATURE 



609 



This instrument, in favourable circumstances of weather, 

 will measure ranges in a few seconds of time with an accuracy 

 of something like 3 yards at looo yards, 30 at 3000. 120 at 6000, 

 and so on. Prof. Barr, of the University of Glasgow, and the 

 lecturer devised the instrument in its main features in 1888 ; it 

 took, however, a period of five years to make a satisfactory 

 naval instrument, and for the past seven years the improvement 

 of the optical and mechanical details has been going on.i 



Fig. 3 shows the same instrument mounted for fortress 

 observation. 



It is claimed for these instruments that they offer a solution 

 —of course not necessarily the only or the best— of the 

 problem of range-finding in all cases where want of portability 

 is not a drawback. 1 



B. and S. Field Range-finder. — Fig. 4 shows a smaller 

 instrument of the same type with a base of 3 feet, which 

 weighs 1 2 lbs. One of these-instruments has been used by Major 

 Guinness in South Africa since the beginning of February, and 

 that ofticer reports that after carrying the instrument on his 

 ammunition wagon over all sorts of ground for six months it 

 was in no way damaged or deranged. The figure shows how 



ngc-liiider. 



the range-finder can be used for taking a distance with prac- 

 tically no exposure of the man. 



The lecturer concluded by describing and exhibiting the 

 electrical telegraph for naval use which Prof. Barr and he had 

 devised at the request of the Admiralty, so as to enable the 

 captain of the ship in the conning tower to receive from the 

 range-taker continuous records of the enemy's distance and 

 to transmit the same and also orders to the guns. The 

 importance of trustworthy means for transmitting orders and 

 other communications from one station to another on a war- 

 ship is now fully realised. Thus, for example, it is reported 

 that in the opinion of Admirals Fournier and de Beaumont and 

 the officer in command, the loss of the French torpedo-boat 

 destroyer Frainee, which occurred about a month ago, was due 

 to the fact that the apparatus on board the vessel for the trans- 

 mission of orders was inadequate. The need for continuous 

 and almost instantaneous transmission of ranges to the gunners 

 will be obvious when it is remembered that in naval engage- 

 ments the range is continually and rapidly altering. 



The lecturer concluded by expressing his thanks to Mr. J. J, 

 Hicks, of London, Mr. Steward, of London, and Messrs. 

 Zeiss, of Jena, for the loan of range-finders to illustrate the 

 lecture. 



1 Readers unacquainted with the instrument are referred for details of 

 Its construction to Transactions of Inst, of Mech. Eng. (1806) or 

 Engineering, 1896 Part i. p. 233, &c. 



NO. 16 j6, vol. 62] 



MECHANICS^ AT THE BRITISH 

 ASSOCIA TION. 



^LTHOUGII no very striking paper was presented to the 

 I section at this meeting, still several papers of value and 



I of considerable interest were dealt with. 



I In the committee of the section two very important pieces of 

 j work were carried out. The committee on small screw gauges, 

 j which has now been at work for some years, presented an 

 interim report in which the difficulties the committee had met 

 I with in obtaining standard gauges were very fully discussed, and 

 j an account of some experiments on different forms of threads, 

 j made by Mr. T. M. Gorham and Mr. W. A. Price in the 

 I laboratory of Prof. liudson Beare at University College, 

 ; London, were described. The committee stated in their report 

 I that they have now every hope of bringing their inquiry to a 

 I successful conclusion, and the committee was therefore re- 

 j appointed and a grant was secured for the necessary expense of 

 I completing the work. 



j A committee was also appointed at Bradford to deal with the 

 question of the resistance of road vehicles to traction. Prof. 

 Hele Shaw read a short paper before the section, drawing 

 attention to the need of modern experiments on the nature of 

 the resistances encountered by vehicles on the common road. 

 He pointed out how the growth of the cycle and motor car 

 industry made information upon this point a matter of the 

 greatest importance. 



There is no doubt that we are- on the eve of a very consider- 

 able increase in mechanical propulsion on common roads, and 

 at present designers of such vehicles have to rely largely upon 

 old experiments with solid steel tyres, and carried out on roads 

 very different indeed from the modern roads. The powerful 

 auto cars which can now be obtained make it comparatively an 

 easy matter to determine the tractive power necessary to move 

 a vehicle with any load upon any type of road, and no doubt 

 the work of the committee will largely consist — after a suitable 

 dynamometer and speed indicator have been arranged for— in 

 carrying out exhaustive experiments with different types of 

 vehicles and different types of tyres on all the various classes of 

 roads now in use. 



A grant of money was secured from the Association for the 

 purposes of this committee, and we have every hope that when 

 the committee submits its report it will justify its appointment. 



In the work of the section papers by local engineers bulked 

 largely. Perhaps the two most interesting and valuable were 

 a paper by Mr. J. Watson, the Waterworks engineer at Brad- 

 ford, in which the new Nidd Valley Waterworks were de- 

 scribed, and the paper by Mr. J. MacTaggart, the Superin- 

 tendent of the Cleansing Department of the City of Bradford, 

 entitled "The Disposal of House Refuse in Bradford." 



In Mr. Watson's paper a short historical summary of the 

 various schemes for supplying Bradford with water was given, 

 followed by a very exhaustive and complete account of the Nidd 

 Valley scheme. This scheme, now rapidly approaching com- 

 pletion, is one which will cost the City of Bradford nearly 

 1,500,000/. and will afford a supply of about twenty million 

 gallons of water per day, and in addition will provide a large 

 compensation reservoir (Gouthwaite) for the land-owners along 

 the Nidd Valley. 



It is essential for such a city as Bradford, where the chief 

 industry is that of the woollen trade, that the water shall be 

 very soft, and, of course, this led to some difficulty in finding a 

 suitable collecting ground for the city supply. 



The section had the opportunity of visiting, under the 

 guidance of Mr. Watson, portions of the works on the Saturday 

 of the meeting. 



In Mr. MacTaggart's paper very valuable information was 

 given as to the most modern methods in a big manufacturing 

 city for the disposal of the daily city refuse. So successful have 

 the various arrangements been, mostly due to the author, that 

 it is hoped in time the destruction of the whole of the refuse of 

 the city will be carried out, not only without creating any 

 nuisance, but without any cost to the ratepayers. The refuse 

 is chiefly dealt with by destructors, and the great merit of the 

 Bradford system is in the utilisation of the clinker produced in 

 the destructor furnaces for various useful purposes, the power 

 to work the machinery required for these purposes, and the 

 lighting of the works all being obtained from the steam generated 

 by the surplus heat of the destructors. A large number of speci- 

 mens were shown to the section of concrete paving-slabs. 



