Feb. 26, 18S5] 



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prcdia Britannica,' lays down the following principle : — 

 ' The fairest available approximate measure of the power 

 of the ships is their displacement or total weight. It 

 always represents power of some kind.' " Sir E. J. Reed 

 adopts this principle, without reserve or qualification, and 

 employs it as an empirical method of determining the 

 relative fighting powers of the ships of our own and the 

 French navies. 



" Bearing this principle in mind, as one accepted and 

 avowed by the Admiralty " he proceeds to compare the 

 displacements of ten of the largest French ships recently 

 built with ten of the corresponding ships of our own navy. 

 The following result is arrived at : — " Looking at these 

 figures, and bearing in mind the doctrine quoted — that 

 superior displacement means superior power, and inferior 

 displacement inferior power — we here see that the Eng- 

 lish ships have been deliberately made inferior by our 

 Admiralty, ship by ship and squadron by squadron." 



We do not know- what authority there is for saying that 

 this "principle" is accepted and avowed by the Ad- 

 miralty. True, it is propounded by Mr. Barnaby, the 

 Director of Naval Construction, in the latest edition of 

 the " Encyclopaedia Britannica" ; but we have not heard 

 that the Admiralty accept and avow it. We hope, for 

 the sake of the scientific reputation of the Naval Depart- 

 ment, that they hold no such fallacious and absurd doctrine. 

 It is surprising to find a scientific man of Sir E. J. Reed's 

 eminence and ability assenting to, and adopting, Mr. 

 Barnaby's so-called "principle." What is stranger than 

 all, however, is that Sir E. J. Reed should not see that the 

 adoption of it is inconsistent with his main contention 

 that our ten newest armour-clads are practically worthless, 

 for quite other reasons, as compared with those of the 

 French, and could be disposed of by the latter " in a very 

 few minutes." 



The average displacement of the ten English ships re- 

 ferred to by Sir E. J. Reed is 9,363 tons, and that of the 

 corresponding ten French ships is 10,470 tons. Applying 

 Mr. Barnaby's principle in the sense in which it is used 

 by Sir E. J. Reed — bearing in mind that " superior dis- 

 placement means superior power, and inferior displace- 

 ment inferior power," and that " the fairest available 

 approximate measure of power " is " displacement or 

 total weight " — we arrive at the conclusion that the fighting 

 power of the ten English ships is rather less than nine- 

 tenths that of the French ships. Had their displace- 

 ments been greater they would, upon the same prin- 

 ciple, have been more powerful than the French 

 ships. But Sir E. J. Reed believes that, apart from 

 displacement altogether, and because of the differ- 

 ent systems of construction employed in the two cases, the 

 English ships could be sunk by the French ships in a 

 very few minutes. The assumptions upon which the re- 

 spective arguments are based are obviously inconsistent 

 with each other. One is that the English ships are infe- 

 rior to those of the French because their displacements 

 are less ; the other is that they are inferior because the 

 details of their construction are not so wisely and effi- 

 ciently designed. Either one or both assumptions may be 

 correct ; but the one has no necessary relation to the other. 

 But we will compare Mr. Barnaby's present principle 

 with an empirical formula previously laid down by him 

 for determining the comparative efficiency of ships of 



war. In the course of a lecture delivered in the Royal 

 United Service Institution, in 1S72, upon " Modern 

 Ships of War,'' Mr. Barnaby put forward the following 

 formula : — 



A X G X H X S> 



= comparative efficiency, 



L x 100 



where A is the weight of armour per ton of ship's mea- 

 surement, G the weight of protected guns and ammu- 

 nition, H the height of battery port-sills above load 

 water-line, S the speed in knots at the measured mile, 

 and L the length of the ship. 



Mr. I larnaby applied this formula to the seven ironclads 

 named in the table given below. In this table we have 

 placed, alongside the names of the vessels, a column 

 which contains their displacements in tons. The next 

 column contains their comparative efficiencies, as com- 

 puted by the above formula ; and the last column contains 

 their comparative efficiencies, upon Mr. Barnaby's new 

 principle that displacement is a fair measure of power. It 

 will be seen that, according to the latter, the most power- 

 ful of these seven ships is the Minotaur, and the next the 

 Warrior. The relative efficiency of the former vessel is 

 three times greater than that given by Mr. Barnaby's 

 previous formula ; and the latter is nearly four times 

 greater. The Warrior and the Minotaur are, according 

 to this standard of comparison, the most powerful of the 

 seven ships named ; while the Minotaur would, upon the 

 same principle, be classed as the most powerful fighting 

 ship the British navy possesses at the present time — with 

 the single exception of the Inflexible. In reality, how- 

 ever, the Warrior and Minotaur are the weakest and 

 least efficient ironclads we possess ; and are invariably 

 classed as obsolete even in the most favourable estimates 

 that are made of the fighting power of the British navy. 



Relative efficiencies r> , - „. 



as computed by Relative effi- 



Names of Displacement Mr. Barnaby's "enc.es upon 



ships in tons formula, Punciple that 



1 A X G X H X S3 Powervaries with 



Nothing further can be necessary to show the fallacy, and 

 the absolute inconsistency, of the views put forward at 

 various times by Mr. Barnaby, respecting the standard 

 by which the fighting power of a ship, or of a navy, may 

 be judged. He has given no justification of either of the 

 methods described ; nor attempted to show that they are 

 approximately reliable. The formula laid down by him 

 in 1872 recognises that the fighting power of a ship of 

 war is made up of various distinct and independent 

 elements — that the amount of armoured protection, as 

 represented by weight of armour ; the power of the 

 armament, as measured by its weight ; the speed, and 

 other qualities constitute elements of fighting power, which 

 have different relative values, and which must be sepa- 

 rately taken into account. We here find the value of 

 manoeuvring pow-er, or handiness in turning, recognised 

 by introducing the length of the ship as a divisor into the 

 iu rmula. This element of fighting power is assumed to 



