282 



NATURE 



[July 22, 1897 



amiable efforts less likely to be crowned by success. In support 

 of this view, we would call attention to the generous letter of 

 thanks from the foreign delegates which appeared in last Satur- 

 day's Times. 



The first sitting for the reading of papers was held in the 

 Imperial Institute on Tuesday, the 6th inst. The Prince of 

 Wales, as President of the congress, delivered an opening 

 address, and was followed by the First Lord of the Admiralty, 

 and by Lord Hopetoun, the President of the Institution of Naval 

 Architects. The congress was then divided into two parts, 

 that relating to Naval Architecture being held in the Main 

 Hall, whilst the Marine Engineers took possession of the East 

 Conference Hall. The first paper taken in the former section 

 was a contribution by M. Emile Berlin. It was on " hardened 

 plates and broken projectiles," and discussed the effect of 

 " Harveyising " steel armour. This paper was to some extent 

 based on one read previously by Mr. C. Ellis, of Sheffield. The 

 author supposed that a cap placed on the point of a projectile 

 would assist in penetrating the plate. This system was first 

 tried in England and met with approval, and judging by M. 

 Berlin's paper he supports the device. The practical success of 

 the Harvey system of treatment — which is in the nature of 

 case-hardening — is now so fully established that it is needless 

 to follow up the subject in this brief sketch ; but, to those who 

 wish to pursue the matter in its more scientific and abstract 

 features, the paper in question will afford both instructive and 

 interesting reading. It must, however, be taken with the 

 illustrations. 



" Non-flammable wood " was the subject of the next paper, 

 contributed by Mr. C: Ellis, of Sheffield. In the process de- 

 described, timber is placed in a cylinder and a vacuum is formed. 

 Steam is then admitted, and the moisture is drawn off with it. A 

 vacuum is then again formed, and a fine spray of a liquid contain- 

 ing certain salts is injected into the cylinder, the fibre being thus 

 thoroughly impregnated by the chemicals. Under these circum- 

 stances the wood will not support flame. So far there does not 

 appear lo be anything very novel in the principles of the pro- 

 cess, though there may be in the details, and possibly the 

 ' ' certain salts " cover an important point upon which information 

 was not given in the paper. The advantage of wood used in 

 warships being " non-flammable " is beyond question. 



In the Marine Engineering Section, at which Sir Edward 

 Reed presided, Sir John Durston and Mr. J. T. Milton contri- 

 buted the first paper, which comprised " a review of the his- 

 tory of the progress of marine engineering in the Royal Navy 

 and Mercantile Marine from the foundation of the Institution 

 of Naval Architects to the present day. " This was one of those 

 elaborate contributions to the literature of the subject which 

 will be invaluable to the historian of the future and the writers 

 of books in general, but which it would be foolish to attempt to 

 abstract here. Its title is sufficient to denote its scope, and the 

 high reputation of the authors is sufficient to stamp the paper as a 

 standard work. A paper by M. Sigaudy was next read. It treated 

 upon water-tube boilers in high-speed ocean steamers, and gave 

 details of actual practice in small vessels, and proposals for larger 

 ones, strongly supporting the suggestion that small tubes, or, as 

 they are called in England, '* express " boilers, should be used 

 on ocean-going vessels. 



On the second day of the congress, Wednesday, July 7, the 

 Naval Architecture Section was opened by the reading of a 

 paper by Sir Edward Reed, on the mathematical theory of naval 

 architecture. This was another monumental paper worthy of 

 the subject and the year. It led to a discussion largely of a 

 nature complimentary to the author, who had managed to 

 compress a large mass of information of a general nature 

 within the limits of his memoir, and to do this without making 

 the subject repulsive by its dryness to the average reader of such 

 contributions. Captain Tuxen, Chief of the Construction De- 

 partment of the Royal Danish Navy, next read a paper, in which 

 he described some of those admirable railway ferry steamers 

 which break their way so remarkably through the ice-bound 

 waters of his native land. The last paper read in this Section 

 was contributed by Mr, J. Johnson, of Gothenburg, and dealt 

 with " graphic aid in approximating hull weights." 



In the Marine Engineering Section, in which Sir Nathaniel 

 Barnaby occupied the chair, the proceedings were opened by Mr. 

 G. W. Manuel reading a paper on " crank and other shafts." 

 Mr. Manuel, as is well known, is the Chief of the Engineering 

 Department of the P. and O, line, and his success in regard to 

 the absence of accidents to the shafting of vessels under his 



NO. 1447, VOL. 56] 



charge has been remarkable. In this respect, however, he 

 has been fortunate in being able to give such substantial pro- 

 portions to this feature in machine design that success is not 

 altogether to be attributed to good fortune ; indeed, it has been 

 said that if Mr. Manuel were to make his shafts of cast iron 

 they would be reasonably safe. By aid of diagrams many in- 

 structive illustrations were given of the manner in which shafts 

 fail, often by fatigue. Mr. Manuel is not an advocate of 

 hollow shafts, and though he gathers countenance for his views to 

 some extent from the fact that hollow shafts are not general in 

 the mercantile marine, we do not think the reasons he puts 

 forward would meet with the support of many naval engineers. 

 The paper was, however, full of information, and was followed 

 by an interesting discussion. 



Mr. Sydney S. Barnaby followed with an excellent paper, in 

 which he gave a lucid explanation of the theory of cavi- 

 tation with screw propellers, that new disease which is the 

 outcome of modern high speeds, and to which marine engineers 

 are now turning their attention. We commend Mr. Barnaby's 

 paper to all naval architects who have not mastered this some- 

 what intricate subject. The last paper read was contributed 

 by Dr. H. S. Hele-Shaw, Professor of Engineering at Victoria 

 University, Liverpool. Its title was " Experiments on the 

 nature of surface resistance in pipes and on ships." This was 

 a most interesting contribution, and might with advantage have 

 occupied more time than could be allotted to it. Doubtless, 

 however, the experiments shown will be brought forward again 

 in other guise. The author's method of studying resistance 

 is to inject water between plates of glass, placing such obstruc- 

 tions to the flow as may be desired, and to throw the image on 

 the screen by the lantern. In order to get a visible result of 

 the streams and eddies, air is injected into the water, or some- 

 times a coloured liquid. The result is most satisfactory, and 

 cannot but lead to considerable light being thrown on this 

 interesting and very debatable subject. It would be impos- 

 sible to follow the author in the details of his paper with- 

 out the aid of graphic representations ; but the effects produced 

 on the screen were mostly illustrated by engravings taken from 

 photographs, and presented with the paper. It is to be hoped 

 Dr. Hele-Shaw will carry his work further, and, by their aid, 

 give substantial guidance in this field of research. 



The foreign delegates and some of the home members of 

 the Institution continued the work of the congress by visiting 

 Glasgow and Newcastle, where a few of the most prominent 

 shipyards — Fairfield, Denny's, and Elswick — were visited. 



LIGHTHOUSE PROGRESS, 1887- 1897. 



T N 1887 some account was given in Nature of lighthouse 

 ■*■ work and progress in the United Kingdom during the pre- 

 ceding fifty years. I propose in this 'article to consider briefly 

 the same subject in connection with the past ten years, so that 

 the whole may form a summary record of what has been attained 

 during the Victorian era in this important branch of optical and 

 mechanical science. 



And, first, it may be asserted that the period of the Queen's 

 reign, distinguished as it is for so many developments of new 

 industries, can boast of none more valuable or more interesting 

 than this now in question. Fresnel's monumental invention 

 in 1819 of the dioptric system of lights was at once welcomed 

 and realised by the French Government, who have since always 

 encouraged and supported the native constructors of lenticular 

 apparatus. But it was only after thirty years from this date 

 that the lighthouse industry was planted in England, if we 

 except the experimental attempts of Messrs. Cookson, of New- 

 castle. The systematic and permanent establishment is due 

 to the public spirit and the enterprise of Messrs. Chance 

 Brothers, subsequently aided by the mathematical talents and 

 personal direction of Mr. James T. Chance, whose services 

 to the Royal Commission on Lights of i860, as well as 

 to the Trinity House, and whose writings on lighthouse optics 

 are widely known. It is said that great pecuniary loss resulted 

 from the first efforts of Messrs. Chance, but they have gone on 

 steadily and alone to the present day, with little or none of 

 official aid or encouragement, and they are certainly entitled to 

 full credit for having done so much and so well for the coast 

 illumination of their own country and the world. 



