February 9, 1893 



NATURE 



353 



in the Museum of Science and Art, Edinburgh, is based upon 

 Bartholomew's map of Edinburgh on the scale of 15 inches to 

 a mile, but the altitudes are taken point bv point from the large 

 town plans of the Ordnance Survey. The model is in many 

 ways original in its mode of construction. Its object is purely 

 geographical, having been suggested by a leading citizen as a 

 method of showing the contrast bet" een the circuitous roads 

 and frequent steep gradients of the old coaching days, and the 

 straighter and more level lines of communication by which 

 modern engineers have overcome the restraint of physical con- 

 figuration. 



In the same number of the Scottish Geographical Magazine 

 there is a paper on the Deserts of Atacama and Tarapaca, read 

 to the Society by Mrs. Lilly Grove, and some interesting notes 

 on South Eastern Alaska by Prof. J.J. Stevenson, illustrated by 

 a map. 



Mr. H. J. Mackinder's third educational lecture for the 

 Royal Geographical Society was given on Friday night, the 

 subject being the belt of Steppe which traverses Asia from 

 west to east. He showed how the distinctive physical and 

 climatic conditions of the Steppe favoured the growth of 

 nomadic nations, every man of whom was a member of the 

 most mobile cavalry force which ever existed. Pastoral pur- 

 suits and marauding were natural to the Steppe peoples, and 

 the descent of th6ir hordes on the settlements bordering the 

 Steppe were turning-points in the history of surrounding 

 nations. Reference to the successive periods of conquest by 

 the Scythians, Huns, Turks, and Mongols showed the power of 

 these nomads on the affairs of other countries, and until the 

 advent of the Steppe-bred Cossacks no western power has ever 

 secured control of the central Asian plains. 



Following on the death of Captain Stairs we have to record 

 the death of his fellow-officer in the Emin relief expedition, Mr. 

 R. H. Nelson. Mr. Nelson returned to Africa, and was in 

 charge of the district of Kikuyu in Ibea, when he succumbed 

 to an attack of dysentery on December 26, 1892. 



THE INSTITUTION OF MECHANICAL 

 ENGINEERS. 

 ""PHE first general meeting for this year of the Institution of 

 ^ Mechanical Engineers was held on Thursday and Friday 

 evenings of last week, the 2nd and 3rd inst., in the theatre of 

 the Institution of Civil Engineers, 



There were two papers set down for reading, as follows : — 

 '' Description of the experimental apparatus and shaping machine 

 for ship models at the Admiralty Experimental Works, Haslar," 

 by R. Edmund Froude, of Haslar ; "Description of the pum ping- 

 engines and water-softening machinery at the Southampton 

 Waterworks," by William Matthews, waterworks engineer 



After the disposal of the usual formal business, the President 

 (Dr. William Anderson) referred to the International Engineer- 

 ing Congress which was to be held in Chicago during the month 

 of August next. He had received a letter from Mr. James 

 Dredge, of London, who had been elected honorary president 

 of the congress. Every one. Dr. Anderson said, knew of Mr. 

 Dredge, so there was no occasion for him to say anything further 

 on that head ; but he trusted that English engineers would take 

 steps necessary to a creditable representation. 



The next business was an alteration in the bye-laws, the chief 

 referring to the class of membership. Hitherto the institution 

 has consisted of members, associates, and graduates. The two 

 latter classes are, however, of small importance and practically 

 the institution is composed of full members. The qualification 

 for membership was that the candidate should be an engineer 

 not under twenty-four years of age ; so that a member might be 

 a Great George Street magnate, or the head of a big engineer- 

 ing firm, down to a draughtsman or the foreman of a machine 

 shop, supposing of course he were an engineer and not simply 

 a mechanic or artisan. These conditions of equality do not 

 appear, however, to meet the views of the council of the institu- 

 tion, so there are to be two classes of engineers on the register, 

 the big and the little. These are to be known respectively as 

 members and associate members, but as far as we can see the 

 broad distinction is that the member has achieved success whilst 

 the associate member has still his way to make. Honour to 

 whom honour is due is a good maxim, but it may be doubted 

 whether the practically self-elected council of an irresponsible 



NO- I2I5, VOL. 47] 



body should be the arbiters, not only of fame, but of profes- 

 sional status. 



Resolutions embodying the proposed changes were moved 

 from the chair, and carried unanimously. It need not be said 

 that the new rule is not retrospective. 



These matters having been settled, the secretary proceeded to 

 read Mr. Froude's paper describing the apparatus in the Haslar 

 establishment, over which, he presides. To make clear the details 

 of mechanism t'iven would be quite impossible without the aid 

 of drawings. These were supplied at the meeting in the shape 

 of wall diagrams, but as members had not an opportunity of 

 studying them beforehand, there were very few who wreableto 

 keep up with the reading of the paper, excepting those who already 

 knew all about the matter. This is mo often — we may say gene- 

 rally — the case in meetings of the technical societies ; excepting 

 always the Institution of Civil Engineers. Before this Society 

 a paper is read on one evening, and, if its importance he 

 sufficient, it is discussed during three sittings, each a week 

 apart. Members have therefore an opportunity of grasping the 

 details of the papers read, and preparing wha' they have to say 

 beforehand. It is for this reason that the discussions before the 

 Civil Engineers have always been instructive. 



Mr. Froude's paper deals with but a fragment of its subject, 

 but it takes the part which was more especially of interest to his 

 audience, namely, the mechanical details involved in the appa- 

 ratus used f >r testing the models by which a forecast is made of 

 the performance of future naval vessels. It is well known that 

 these forecasts are made possible by the late Mr. Froude's dis- 

 covery of the law of "corresponding speeds," so that the speed, 

 with a given power, of the full sized ship can be deduced from 

 the performance of the model. The way in which the late Mr. 

 Froude carried out his investigations, and how the original ex- 

 perimental works grew up at Torquay, under the wise encourage- 

 ment of the Admiralty, are well known to all interested in 

 physical science. It would bedifficult to overestimate the good 

 that has followed this work ; for one thing it has done much 

 to put us on an equality with our old rival-;, the French — long, 

 indeed, our masters in the science of ship design. Perhaps there 

 is nothing upon which we could better found our claim to naval 

 supremacy — in this long era of naval peace — than the possession 

 of the only naval testing tank of its kind. It is a distinction 

 we shall probably not long he able to boast, f )r the Russians, 

 Italians, and Americans all contemplate constructing establish- 

 ments of a like nature. 



The paper commences with describing the principal features 

 of the present Admiralty experiment establishment at Haslar. 

 As at the former works at Torquay, the chief object consists of 

 a long covered water-way, in which models of ships are towed 

 to ascertain their resistance. The towing is done from a dyna- 

 mometer carnage driven at definite speeds by a stationary engine 

 working a wire rope. The models are made of hanl paraffine, 

 generally about 14 feet long, and something upwards of I inch 

 in thickness as finished. They are cast in a mould with an 

 allowance of about \' for finishing the shape. The latter 

 operation is done by hand, guidance grooves being cut 

 in the model, so that the exact form may be preserved. 

 The working of this shaping or copying machine, and the 

 way in which it enables the lines of a drawing to be 

 translated into model form, constitute one of the most interest- 

 ing parts of the installation. The water-way, canal, or tank at 

 Haslar is nearly 400 feet long, and of nearly uniform section 

 throughout. The sides are of concrete and vertical, and the 

 railway, on which the dynamometer carriage runs, is bedded on 

 the tops of the side walls of the water-way, in place of being 

 suspended over the water from the roof, as in the original design. 

 The experimental carriage, which has to be nearly 21 feet gauge, 

 is a trussed structure. Its principal peculiarity consists in the 

 fact that the members of the several trusses composing it are 

 wooden trunks or boxes about 4" square in cross sections, made 

 of %" deal, and put together with screws and shellac varnish. At 

 the joints formed by the intersection of the various members of 

 the trusses, the sides of the boxes are made to overlap one 

 another over a large area, providing a large surface for screwing 

 and for the adhesion of the shellac varnish. The dimensions of 

 the boxes forming the several members of the girders are 

 designed so as to bring the sides of the boxes into the right 

 planes to suit these overlaps. The whole structure thus pro- 

 vided is remarkably rigid and light. The general design of the 

 carriage is arranged so as to leave clear a sort of central alley 

 provided with a railway, the rails of which are close to the sides 



