DISCOVERY 



279 



THE PREVENTION OF WAR: A SUGGESTION 



To the Editor of Discovery 



Sir, 



I quite expected some correspondence in the August 

 issue regarding the question of " War " raised in your 

 " Notes " for July. As this does not appear to have 

 materiaUsed, I venture the following remarks. Let us 

 assume that war is not a biological necessity, that is, not 

 necessary for the good of the race ; that the future of 

 the race is unaffected one way or the other by war. War, 

 however, does hami the majority of its contemporaries 

 and their immediate descendants, and is, therefore, a 

 crime. Let us, therefore, perhaps through the League 

 of Nations, declare boldly that war is a crime, and that 

 those who declare war are criminals ; let us enact in 

 every country an unbreakable law that on the declaration 

 of war all the members of the Cabinet (or its equivalent) 

 be shot within twenty-four hours as criminals. Of 

 course, some wars may be righteous wars, and in such 

 cases, without a doubt, the statesmen concerned would 

 patriotically give up their lives for their country by 

 declaring war, as the soldier is expected to give up his 

 by fighting a war for he knows not what. 



The sudden dislocation of government in the two 

 countries party to the dispute, wliich had occasioned the 

 declaration of war, would, of course, give an opportunity 

 for a further examination of the grievance by a fresli 

 set of men, with the certain result of a peaceful settlement, 

 the only deaths from the war being a few fiery old politi- 

 cians who must have been tired of life anyway. 



Yours/ etc., 

 Percy J. Stirrup. 

 Laxgdale, 



Church Lane, Oxhey, 

 Nr. Wolverhampton. 

 July 28, 1922. 



[The freshness of this letter would be quite spoilt by 

 any editorial comment. . . . — Ed.] 



THE INVENTION OF THE PILOT CABLE 



In Discovery for June we printed a letter from 

 Dr. Cargill Knott, the secretary of the Royal Society of 

 Edinburgh, pointing out that M. Wilham Loth's discovery 

 of the method of guiding a sliip into port by detecting 

 electrically a cable laid in the bed of the channel, of wliich 

 a description appeared in the April issue, had been 

 anticipated by the experiments of Mr. C. A. Stevenson 

 thirty years ago. M. Loth has now written in reply to 

 Dr. Knott, but his letter is too long and his diagrams too 

 technical to warrant their publication in full ; the gist 

 of liis case, however, is given below. 



The point at issue is : was it possible with the apparatus 

 described by Mr. Stevenson in 1892 to guide a ship safely 

 along a channel into port ? M. Loth has examined the 

 problem in detail and has concluded that it was not. 

 He agrees that Mr. Stevenson's detecting apparatus will 

 detect a cable's presence, but he declares the method as 

 described wU not allow a ship to be steered safely into 

 port. There is, of course, a large difference between 



merely detecting the presence of a cable and accurately 

 steering a sliip by knowing where the cable is. Mr. 

 Stevenson's description is too vague ; he talks about his 

 detector being on the ship, or let down by rope or cable, 

 or coiled round the hull of the vessel. But this describes 

 the detector too loosely, and a ship could not in fact be 

 steered safely in tliis way. The problem is reaUy complex 

 and difficult, and several problems had to be studied and 

 several difficulties to be removed, all subsequent to 

 Mr. Stevenson's work, before the problem of guidance 

 might be described as solved. 



M. Loth declares that Dr. Ivnott, in putting forward 

 Mr. Stevenson's claim to recognition, has mistaken the 

 detection of a submarine cable for the solution of guidance. 

 But really, unless the method leads to safe guidance, it 

 cannot be said to anticipate his o^vn work. And also, 

 unless it does, it can hardly be said to have been novel 

 in principle, even in 1892. For the detection of a sub- 

 marine cable by electromagnetic means was first accom- 

 plished by Sir \\'illiam Preece eight years before. 



M. Loth declares that liis own system of detecting a 

 submarine cable is essentially different from Mr. Steven- 

 son's and that his system allows ships to be safely guided 

 into port, whereas Mr. Stevenson's does not and never 

 has done. During the war the Admiralty did not use 

 Mr. Stevenson's system because they did not think it 

 safe enough for their sliips ; they adopted a very different 

 system, yi. Loth's system was, however, adopted by 

 the French Admiralty. 



Sir, 



BANANA SEEDS 



To the Editor of Discovery 



In the article Sex and its Determination in your 

 August number, the following sentence occurs : " The 

 banana, for instance, never sets seed." I used to think 

 so too till 1 88 1, when my teeth jarred on a banana seed 

 and warned me ever since not to assume that your teeth 

 will go safely through a banana. It is, I know, popularly 

 assumed that the plant does not seed, and I have read 

 eloquent accounts of it as one that has forgot to seed ; 

 but it is well known to botanists that the plant does seed, 

 as will be seen from the following extracts from Alphonse 

 de Candolle's Origin of Cultivated Plants : 



Page 305 : " No one pretends to have found in America, 

 in a wild state, varieties with fertile fruit, as has happened 

 in Asia." 



Page 307 : " The cultivated varieties seldom produce 

 seed." 



The first extract probably gives the cue to the myth 

 of the banana not seeding, as those sold in this country 

 all come from the West Indies. I mj'self lived many years 

 in India before coming across the seed, and then not till 

 I was sent to Bengal. Here I came across it three or 

 four times altogether in eating the fruit, but I frequently 

 used to see fine large bunches on plants growing on the 

 embankments I had to look after, and used to wonder 

 why the thrifty native of India did not gather them, till 

 a rather comical incident revealed the cause. 



