- JO*- 



NATURE 



[September i6, 1909 



the engine-power is fully 60 per cent, greater than that 

 of their swiftest predecessors, yet no similar allowance 

 appears to have been thought necessary by some critics, 

 who assumed that performances on the earher voyages 

 represented the maximum capabilities of the vessels. Sub- 

 sequent events have shown this view to be fallacious, and 

 have justified the recommendation of the Turbine Com- 

 mittee and the action of the Cunard directors. Allegations 

 made in regard to excessive coal consumption have also 

 been disproved by experience, and in this respect the 

 anticipations of the committee and of Mr. Parsons have 

 been fully realised. 



The marvellous regularity maintained by the Mauretaiiia 

 on a long sequence of consecutive Transatlantic passages 

 — made under varying and in many cases very adverse 

 conditions of wind, weather, and sea — illustrates once 

 more, and on an unprecedented scale, the influence which 

 large dimensions have upon the power of maintaining speed 

 at sea. Starting from the eastward passage, beginning 

 on February 3 last, and taking twelve passages (westward 

 and eastward) which followed, the average speed for the 

 thirteen passages, approaching 40,000 sea miles in length, 

 has been 25^ knots ; the lowest average speed in the series 

 has been 25-2 knots, the highest average speed 25-88 knots. 

 Many of the winter passages in this series were made in 

 winter weather against strong winds and high seas, which 

 would have considerably reduced the speed of her pre- 

 decessors, but had small influence on the Mauretania. 

 In many instances delays have been caused by fogs. 



On seven consecutive passages made since the beginning 

 of last May the average speed of the Mauretania in cover- 

 ing about 20,000 sea-miles has been 25-68 knots, the mini- 

 mum speed for the passage having been 25-62 knots and 

 the maximum 25-88 knots. On her contract trials the 

 Mauretania maintained an average speed of 2604 knots 

 for a distance somewhat exceeding 1200 knots, the steam- 

 ing time being rather less than forty-eight hours. On the 

 passage when she averaged 25-88 knots, she ran 12 15 knots 

 from noon on June 17 to noon on June 19 (about forty- 

 -six hours), at an average speed of 26-23 knots, and by 

 noon on June 20 had covered 1817 knots at an average 

 ■speed of 26-18 knots for sixty-nine hours. The ship has, 

 therefore, surpassed on service her performance on the 

 contract trial. 



In view of the foregoing facts and of others of a similar 

 nature, it is reasonable to assume that as experience is 

 enlarged and information is accumulated in regard to forms 

 •of propellers likely to prove most efficient in association 

 with quick-running turbines, sensibly improved perform- 

 ances will be obtained. .'\t present, in comparisons made 

 "between the efficiency of reciprocating-engined ships and 

 turbine-engined ships, the former have the great advantage 

 attaching to long use and extended experiment; but this 

 Is not a permanent advantage, and it may be expected that, 

 good as the position is to which the marine steam turbine 

 "has attained in the brief period it has been in practical 

 ■use, that position will be gradually improved. Whether 

 or not other forms of propelling apparatus in their turn 

 will surpass the steam turbine it would be unwise to pre- 

 •dict. Internal-combustion engines are regarded in some 

 quarters as dangerous and probably successful rivals to 

 ■steam turbines in the near future. 'Within certain limits 

 of size, internal-combustion engines no doubt answer 

 adrnirably : but as dimensions and individual power of the 

 engines are increased, the difficulties to be overcome also 

 rapidly increase, and the fact is fully recognised by those 

 "having the best knowledge of those types of prime movers. 

 On the ■whole, therefore, it seems probable that the turbine 

 will not soon be displaced, whatever mav happen 

 ■eventually. 



An Imperial Navy. 



Three centuries ago a great English seamen and coloniser 

 wjote these words : — 



" Whomsoever commands the sea commands the tra'de ; 

 Whomsoever commands the trade of the world com- 

 mands the riches of the world, and consequently the 

 world itself." 

 In these ■s\'ords Sir Walter Raleigh clearly expressed the 

 •doctrine of " sea-power," which in recent times has been 

 ■emphasised by Admiral Mahan of the United States Navy 



NO. 2081, VOL. 81] 



and other writers. Twenty years ago when the movement 

 began which has been followed by an unprecedented series 

 of shipbuilding programmes, great additions to the per- 

 sonnel of the Royal Navy and large expenditure on 

 improvements of existing naval bases and the creation of 

 others at important strategical points, the same truth was 

 expressed in a report made by three distinguished Admirals, 

 one of whom, Admiral of the Fleet Sir Frederick Richards, 

 subsequently became First Naval Lord of the Admiralty, 

 and did much to give effect to the policy he had joined 

 in recommending. One passage in this report may be 

 quoted : — " No other nation has any such interest in the 

 maintenance of an undoubted superiority at sea as has 

 England, whose seaboard is her frontier." "England 

 ranks amongst the great Powers of the world by virtue of 

 the naval position she has acquired in the past, and which 

 has never been seriously challenged since the close of the 

 last great war. The defeat of her Navy means to her the 

 loss of India and her Colonies, and of her place amongst 

 the nations." 



The " maintenance of an undoubted superiority at sea " 

 in existing circumstances and in face of foreign competi- 

 tion is no easy task, and it is good to know that the 

 Dominions beyond the Seas are ready to take a share of 

 the heavy burden of Empire. In what way eftect can best 

 be given to this fundamental idea it is not easy to decide. 

 It is necessarily a matter in which the views of all con- 

 cerned must be considered, and a policy determined on 

 w'hich shall command hearty support from all portions of 

 the Empire. It may be presumed that the arrangement 

 of such a policy has been the chief object of this year's 

 Defence Conference. The decision which may be reached 

 and the action taken must exercise momentous influence 

 upon the destiny of the Empire. Universal approval has 

 been given to the arrangement for that Conference, and 

 this is a happy augury of its ultimate success in framing 

 a satisfactory scheme for the construction and maintenance 

 of an Imperial Navy. Many valuable suggestions have 

 been made by British and Colonial authorities as to the 

 great lines on which such a scheme should be drawn, but 

 this is not the place to enter upon a discussion of the 

 subject. It may be permitted, however, as a sequence 

 to the preceding remarks on over-sea transport, to remark 

 that the protection of trade routes between the Mother 

 Country and the Dominions beyond the Seas constitutes 

 an essential duty ; in the performance of which duty, 

 especially in portions of trade routes adjacent to the 

 Colonies, naval forces maintained by the Colonies may 

 render valuable service. Such a policy in no ■way infringes 

 the fundamental condition that supremacy at sea ultimately 

 depends upon battle-fleets ; while it recognises the fact, 

 which past struggles have demonstrated, that behind and 

 beyond the work of battle-fleets lies the need for adequate 

 protection of commerce and communications. Moreover, 

 it leaves Colonial Governments unfettered in making 

 arrangements for the execution of that portion of the . 

 general scheme of defence which they may undertake ; and 

 there can be no inconvenience or loss from such in- 

 dependent action provided the scheme of Imperial defence 

 has been considered as a whole, and an understanding 

 reached in regard to the distribution of the work. At 

 present the Mother Country alone possesses experience and 

 means of manufacturing warships and armaments, so that 

 gradual developments, requiring time and experience, will 

 be necessary before the Colonies can become self-support- 

 ing in these respects should they desire to do so. On the 

 side of personnel and its training also the Royal Navy 

 must be the great school for all parts of the Empire. 

 Finally, the full utilisation of Imperial defensive forces 

 demands the existence of a complete understanding and the 

 pre-arrangement of a common plan of campaign. In order 

 to meet this essential condition there must be an Imperial 

 staff. 



The burden of naval defence has hitherto been borne 

 almost entirely by the Mother Country. What the ■n'eight 

 has been is hardly realised until the figures for expenditure 

 are examined. As indications of what is involved in 

 creating and maintaining a modern navy of the first class. 

 it may be mentioned that in the ten financial years of 

 the present century (including the current year iqog-io^ 

 the total expenditure on the Royal Navy amounts to 328 



