\iTURE 



5?5 



THURSDAY, AUGUST 27, 1908. 



FLUID RESISTANCE AND SHIP 

 nWPULSION. 

 Resistance of Ships and Screw Propulsion. By Naval 

 Constructor D. W. Taylor, U.S.N. Pp. i.\ + 234. 

 New York : The Macmillan Co. ; London : Mac- 

 millan and Co., Ltd., 1907.) Price los. net. 



ATRXT-BOOK dcalinfj with these subjects, on 

 the basis of scientific principles and experimental 

 investigation, in a form suitable for the use of students, 

 was much required when, fifteen years ago. Naval 

 Constructor Taylor undertook the task. He was e.K- 

 ceptionally qualified for the work, having graduated 

 at the Naval Academy at .\nnapolis, and subsequently 

 passed, with distinction, through the courses of study 

 in naval architecture at the Royal Naval College at 

 Greenwich, where he had the great advantage of at- 

 tending lectures by Prof. Cotterill, F.R.S., and the 

 instructors in naval architecture. Mr. Taylor's book 

 was largely in the nature of a compilation, and based 

 on work done by British writers, and especially on 

 that of William Froude and Rankine. Due acknow- 

 ledgment of this indebtedness was made, but the 

 volume also contained much original work. Its pre- 

 sentation of facts and principles was fresh and admir- 

 able in form. The style was clear and terse; mathe- 

 matical investigations were numerous and well 

 arranged ; readers were referred to original sources of 

 information ; and within two hundred pages a great 

 mass of information was compressed. In these cir- 

 cumstances it was natural that the volume should be 

 widely circulated both in this country and in the 

 United States. It has been out of print for some 

 years, and all interested in these subjects have hoped 

 for a revised edition in which would be embodied 

 work done since 1893 in connection with the resist- 

 ance and propulsion of ships. The intervening period 

 has been marked by numerous and valuable experi- 

 mental investigations conducted in tanks which have 

 been established in this country and abroad on the 

 model of that first constructed near Torquav by the 

 late William Froude about forty years ago. 



One of the best equipped experimental establishments 

 of this kind is that in the \Vashington Navy Yard, over 

 which Mr. Taylor has presided, and for the designs 

 of which he was largelv responsible. It is much to 

 be regretted, therefore, that the pressure of his official 

 duties should have prevented Mr. Tavlor from re- 

 writing his book and bringing it up to date. This is 

 particularly true in regard to the sections of the work 

 which deal with screw-propellers. Mr. Tavlor has 

 conducted some of the most important series of ex- 

 perimenis on model propellers yet made, and his 

 papers published in the Transactions of the British 

 and American Societies of Naval Architects are both 

 valuable and suggestive. Had it been possible for 

 him to summarise and digest his own results and 

 those obtained bv Mr. R. E. Froude, Prof. Durand 

 and other experimentalists, he would have conferred a 

 great service on all who are connected with ship pro- 

 NO. 2026, VOL. 78] 



pul>ion. It may be hoped that he will yet attempt 

 this task, for which no living writer on the subject 

 is better qualified. 



Taking the book as it stands, as an avowed reprint, 

 it will be welcomed by shipbuilders and marine 

 engineers, who will find therein an excellent epitome 

 of modern theories of resistance and propulsion, and 

 Useful illustrations of the applications of these theories 

 in practical ship-designing and the estimate of engine- 

 power required for given speeds. Outside profes- 

 sional circles there are many persons interested in 

 problems of fluid resistance who will be glad to have 

 an exposition of the modern experimental methods 

 which we owe chiefly to the Froudes, and a sketch of 

 the stream-line theory of resistance on which those 

 methods are based. 



Thanks to the generosity of Mr. Yarrow, who has 

 himself been responsible for the production of many 

 vessels of exceptional speed and novel type, there is 

 now a practical certainty of the establishment at 

 an early date, in connection with the National Physi- 

 cal Laixiratory, of an experimental tank embodying 

 all accumulated experience and having the most 

 modern and perfect equipment. It is true, no doubt, 

 that the results of model experiments can only be 

 applied within certain limits, and that they must be 

 associated with analyses of full-scale trials of ships 

 and propellers. The experience of forty years on the 

 lines laid down by William Froude has established the 

 enormous value of his experimental method in the 

 design and propulsion of steam-ships of novel types- 

 and unprecedented speeds. There remains, however, 

 the necessity for more extended research in order that 

 the influence of variations in forms and proportions 

 of ships and the characteristics of screw-propellers 

 may be better understood. Large economies are un- 

 doubtedly still possible in the propulsion of steam- 

 ships, and will be realised when systematic model 

 experiments have been carried out by a competent 

 staff, working on lines which have been laid down in 

 conference with practising naval architects and 

 marine engineers. 



Herr Wcllenkamp proposed recently' a method of 

 experimental research on fluid resistance and ship- 

 propulsion which would involve much less expendi- 

 ture on experimental establishments and their equip- 

 ment than is needed for tanks on the Froude system. 

 In principle the method is identical with that adopted 

 by Beaufoy in experiments made in this country for 

 the Society for the Improvement of Naval Architec- 

 ture towards the end of the eighteenth century. The 

 motion of the model through the water is produced 

 by a falling weight. Herr Wellenkamp was not ac- 

 quainted with Beaufoy 's experiments when he devised 

 his apparatus, nor was he aware that other experi- 

 mentalists—including the Hon. Charles Parsons- 

 had used similar arrangements in recent years. He 

 has worked out the idea in a most ingenious and 

 thorough manner, and used a large tuning-fork as 

 the time recorder, which marks on the revolving sur- 



1 In a paper read at the meetings of the Insttution of Naval Architect . in 

 April last. 



