July 26, 1877] 



NATURE 



247 



lished of British Labyrinthodonts. The authors, how- 

 ever, do not recognise the articular surfaces on the 

 exoccipitals of Loxomma as the two condyles ; and they 

 speak of a concave articular surface as taking the place 

 of a condyle or condyles on the basioccipital bone. The 

 condyles in all Amphibia are produced by the exoccipital 

 bones, and such a character is not a special evidence of 

 the affinity of Loxomma with fishes. The number also 

 contains several interesting papers on local natural his- 

 tory and antiquities, and the address of the president, 

 the Rev. G. Rowe Hall. 



LETTERS TO THE EDITOR 



[TAe Editor does not hold himsilf responsible for opinicns expressed 

 by his correspondents. Neither can he undetiake to return, 

 or to correspond with the writers of, rejected manuscripts. 

 No notice is taken of anonymous communications. 



The Editor urgently requests correspondents to keep their letters as 

 short as possible. The pressure on his space is so great that it 

 is impossible otherwise to ensure the appearance even of com- 

 munications containing interesting and novel facts. ] 



The "Inflexible" 



My attention has been called to an article on the Inflexible, in 

 Nature (vol. xvL, p. 201), and I shall be much obliged by 

 your inserting a few remarks, which I shall make as short as 

 possible. On the general subject of the article I do not propose, 

 nor would it be proper for me, to say a word. I am concerned 

 only with the concluding remarks of the writer on a letter of 

 mine to the Times. Nothing has appeared to me more astonisli- 

 ing than the use, or rather abuse, which is occasionally made of 

 the report of Lord Dufferin's committee on ships' designs. If 

 their authority can be claimed for any statement, I see on all 

 sides a readiness to claim it. Should anything they have said 

 militate against a favourite view, their authority is depreciated, 

 and a comparison is sometimes invidiously dra\vn between the 

 supposed opinion of the majority and that of an intelligent 

 minority. Now if I. be included with the unintelligent majority 

 I am quite content to find myself in such good company ; but 

 if, on the contrary, I am included in the minority, I utterly 

 and absolutely refuse a compliment at the expense of my 

 distinguished colleagues, with whom I shall always esteem 

 it no small honour to have served. In fact I am not aware of 

 any scientific point on which that committee was not unanimous. 

 The writer of the article in question in common with many 

 others, seems to have entirely mistaken the position of that 

 committee. He seems to think their duty was to make their 

 report a treatise on Naval Architecture. The absurdity of such 

 a notion is apparent on the face of it. In fact they were required 

 to give an opinion on certain designs of ships submitted to them 

 as to their being in accordance with the latest developments of 

 the theory of naval architecture. It was no part of their duty 

 to descant on the principles which were successfully applied in 

 such designs ; but undoubtedly if they observed that in any 

 direction caution was necessary, they were bound to remark it. 

 In none of the designs was there any indication of a tendency to 

 curtail initial and maximum stability of their due proportions ; 

 had there been they would certainly not have failed to call atten- 

 tion to it. But while they found the design of the Devastation 

 in all respects sound, they yet thought it desirable that the range 

 of stability should in future designs be somewhat enlarged. In 

 recommending such enlargement they by no means committed 

 themselves to any such'absurd dictum as the vn iter imagines — that 

 range of stability is all that is requisite for the safety of a ship. 

 But as I have already said, to have laid down all the other 

 requisites of a good ship would have been to write a treatise. 



Again, whatever credit according to some, or discredit accord- 

 ing to others, is due to the design of a ship like the Inflexible 

 with an armour-plated central citadel with unarmoured bow and 



stem, that credit or discredit cannot be justly imputed to the 

 committee. Mr. Reed, in his evidence, had brought a design 

 with some of the .eading" features of such a ship before them, 

 and it occupied a considerable "share 'of their attention. Now 

 what do they say on this subject?— "It is not by any means 

 certain that some method may not be devised of securing 

 the requisite reserve buoyancy by other means than armour 

 plating." And after giving a sketch of what such a ship would 

 be, they conclude thus :— " In the absence of any practical 

 experience of the effect of large shells or of torpedoes upon such 

 a structure as we have in view, it is Impossible to say with con- 

 fidence that the object aimed at would be thus attained, but, if it 

 were, consequences of so much^ importance and value would 

 follow that we think it. right to indicate this line of inquiry as 

 worthy of experimental investigation." 



How far such a,bare suggestion of experimental inquiry is 

 from the recommendation of such'a'stnicture for adoption must 

 be evident to your readers without further comment. 



United University Club, Pall Mall, Joseph Woolley 



July 20 



[The above letter from Dr. Woolley is what might have been 

 expected from a man of his eminence in the science of naval 

 architecture, writing under the restraint of his nomination by the 

 Government to a membership of the Committee which is to 

 report upon the stabiUty of the Inflexible. It is no doubt to the 

 concluding words of our first article on this subject (Nature, 

 vol. xvi. p. 203) that Dr. WooUey's letter refers, and we at 

 once admit that there is very great force in the argument which 

 he now employs. The particular point in question is a very 

 simple one. In his letter published in the Times of July 19, 

 Mr. Barnaby wrote: — "According to our estimate the ship, 

 when fully armed, stored for fighting, and manned, will have, 

 independently of the unarmoured ends — i.e., supposing them 

 not to exist — a range of stability of 48 deg. The Committee on 

 Designs considered that 40 deg. was sufficient range for a sea- 

 going unmasted ship." On the following day a letter appeared 

 from Mr. Reed commenting on the impropriety of assuming the 

 non-existence of the ends, pointing out that it was 50 deg. and 

 not 40 deg. that the Committee spoke of as the minimum angle 

 of vanishing stability, and adding that when the Committee put 

 forward " range of stability " as "the one measure of safety " to 

 be considered, "they stated the most dangerous doctrine which 

 probably has ever been propounded in connection with the 

 science of naval architecture." Now, on reconsidering the whole 

 question, we are inclined to think that these words were not, in 

 point of fact, quite fair to the Committee, because there was 

 probably no member of the Committee who would have asserted 

 or admitted that "range" was the one and only measure of 

 safety to be considered. Dr. Woolley, Mr. Froude, Sir W. 

 Thomson, and probably some other members of the Committee, 

 doubtless knew perfectly well that the length of G z from point 

 to point was not only as important as "range," but far more 

 important in all cases of limited range ; and it is now obvious, 

 with the present letter of Dr. Woolley before us, that the absence 

 of any reference to the fact is attributable to the limited extent of 

 the Committee's inquiry. There is great force in the remark that 

 it was no part of the duty of the Committee to compose a 

 treatise on naval architecture. On the other hand we are bound 

 to deny that our remarks were penned under a contrary im- 

 pression. Our view is that the use to which Mr. Barnaby has put 

 the Report of the Committee proves that the scientific men who 

 composed it would have done well to have employed more guarded 

 Language, and to have recognised in some manner the insufficiency 

 of range only as a measure of safety. When they are found 

 speaking of a certain angle of vanishing stability as being 

 "sufficient to ensure the safety "of ships, it must be admit- 

 ted, even by Dr. Woolley and his colleagues, that some 

 risk of misconstruction was incurred. That misconstruction, or 

 perhaps we ought in this case to say misuse — or even "abuse," 

 as Dr. Woolley expresses it — has occurred in the present 

 case is manifest, because Mr. Barnaby seized hold of the 

 Committee's dictum as to range, and ignored altogether the very 

 serious question of the amount of the stability. What makes 

 the matter more important than usual in the present case is that 

 the curve of stability due to the citadel of the Inflexible only is, 

 no doubt, a low and flat cur\'e, G z being everywhere so small 

 that in order to bring the stability up to a safe amount its range 



