I04 



NA TURE 



[May 31,1 b94 



further confirmed by Dr. C. Haussermann last year, who has 

 isolated a definite crysiallised sodiuin perchromate, as described 

 in ihe jfjurnal fur Pniktische Cliemie, (\Mo\ei in Nature in 

 the .notes given July 27, 1893, p. 300. Thomas Fairley. 



Cataloguing Scientific Papers. ' 



The recent circular issued by the Royal Society anent the 

 indexing of scientific literature affords me a pretext for suggest- 

 ing in your columns a reform which I have long thought to he 

 urgently required. It is that henceforward all scientific publica- 

 tions should be issued in only one volumeper annum— in parts, if 

 necessary, but consecutively paged and with only one index — 

 and that this volume should be primarily referred to by the year 

 of its publication, not by its number since the first issue of the 

 publication. Two advantages would accrue from this system. In 

 the first place, the date of all quoted work would be fixed ; in the 

 second place, the finding of the abstracts of papers published 

 elsewhere, printed in the journals of scientific societies, would be 

 rendered more easy. A little reflection will show that these 

 benefits are not trivial. For example, suppose an author refers 

 to a paper by Smith published in Nati'RE, vol. xi. I have not 

 (may 1 be pardoned for saying so !) the slightest idea when 

 Natire was first issued, nor do I remember whether one or 

 two volumes of this periodical appear per annum. I am there- 

 fore totally in the dark as to whether Smith's work is one year 

 old or twenty years old, and consequently I am ignorant whether 

 he is likely to have used the most modern appliances in his re- 

 search, and whether he is likely to have been contradicted by 

 subsequent observers. .-Xgain, I am referred by an author to a 

 paper by Schmidt, in the fScrichte of the German Chemical 

 Society, vol. xx. Not pis^essing this journal, I hope to be able 

 to find an abstract of the paper in question in the Joiirnnl of the 

 Chemical Society, to which I subscribe ; but as I have no notion 

 in what year vol. xx. of this Btrichle was published, I have to 

 search through numerous indexes in order to find the abstract. 

 A search for previously published work is already sufficiently 

 ditTiciilt to cause many to shrink from the task ; ten years hence 

 it may be expected to be the most laborious and thankless work 

 which the investigator has to perform. A. G. Bl.oXAM. 



.May 19. 



Clavatella Prolifera. 



This hydrozoan may be added to the list of the Jersey marine 

 fauna. It occurs in rock pools on the higher littoral between 

 the Point des Pas and Gorey, and probably at other places round 

 the coast. I often found three or four colonies in one small 

 pool ; but the number of polypites in a colony was very small — 

 generally two or three, rarely four, and only in one case five. 

 The stolon runs along in the chinks of the Melobesia that grows 

 over so many of the pools, hence it is not an easy matter to 

 obtain specimens there. The walking-buds, however, were 

 fairly plentiful. 



May I ask if any correspondent of Natijre has ever seen the 

 walking-bud of JiUiilheria, in which both extremities of the 

 bifurcated arms are said to consist of a ball of thread-cells? 



May 22. Henry Sciierren. 



THE DESTRUCTIVE l.l-l-l-CfS OF SMALL 

 PROJECTILES} 



'T'HK effects of small projectiles when driven at high 

 •*• velocity through the ti^sues of the brain have 

 always excited the deepest interest, for very obvious 

 reasons. 



This interest must always be two-sided, namely : (i) 

 Physical ; (2; Pathological ; and it is upon these two 

 points of view that I propose to speak to you this 

 evening. 



Conceive a cylindrical bullet with a conical head (ly- 

 ing through the air some ten or fifteen times faster than 

 an express train. 



We have now to study what it is doing in its aerial 

 flight, and what will happen when that terminates by the 

 projectile striking both hard and soft substances. 



This embodies matter for the purely physical side of 

 the work. 



> A Ieciur« delivcrtd at the Royal Iniiiiution on April 6, by Prof. Victor 

 HoriU), K.K.S 



NO. 1283, VOL. 50] 



But imagine, further, that the hard and soft substances 

 just mentioned are the skull and brain respectively, what 

 will happen then ? 



This is the pathological part of the question, and it is 

 one of the greatest moment ; for whereas it is true that a 

 few persons do survive being shot in the head, the large 

 majority die ; and if is my object to show you how a 

 combination of physical and pathological experiments 

 has revealed the reason why the majority do die, and re- 

 vealed it, fortunately, so distinctly as to suggest means 

 for warding off the fatal result. 



(i) Physical Considerations. — First take the case of a 

 bullet flying through the atmosphere. Here in this 

 extremely beautiful photograph, kindly lent me by Prof. 

 Boys, you observe that the bullet drives before it a wave 

 of compressed air. Now this compressed air-wave is 

 what is popularly called the wind of the shot, and to it 

 used to be ascribed by military surgeons a certain pro- 

 portion of deaths. The origin of this theory is difficult 

 to discover, as the only case I am aware of in which the 

 post mortem examination did not reveal h.vmorrhage, 

 fracture, &c. indicating that the shot had actually struck 

 the body (.though without injuring the highly elastic 

 skin) is the instance given by the great Russian military 

 surgeon Pirogotil", in his interesting surgical experiences 

 of the Crimean war. Even this instance finds a priori a 

 more reasonable explanation in syncope, and we shall 

 see directly that the wind of the shot not only cannot, 

 under any circumstances, kill a man, but also that its 

 energy is far too slight for it to have any destructive 

 effect whatever. It is rather curious to find that but few 

 attempts have been made directly to estimate the wind 

 of the shot, and those by Pelikan and others are only for 

 large shot and by too coarse methods to be applicable 

 in the case of a bullet, as the following experiment 

 shows. 



An extremely light vane of paper carrying a delicate 

 mirror is suspended to a cocoon fibre, and carefully pro- 

 tected from currents of air in the room. A very gentle 

 puff causes the vane to fly out most vigorously, yet we 

 shall find that the 380 bullet moving a thousand feet a 

 second may pass within eight inches of it without causing 

 the least deviation of a ray of light reflected from the 

 mirror. It is only when the bullet passes within an inch 

 or two of the edge of the vane that there is some slight 

 rotation. The'303 magazine service rifle, with a velocity of 

 twice that of the larger bullet, produces little more than 

 the same result. It is therefore obvious in this case that 

 the far higher velocity is more than compensated for by 

 the lesser sectional area of the projectile displacing the 

 air. .Although there was no proof of much displacement 

 of the air, it was pretty generally held that when the 

 bullet entered any substance the compressed air driven 

 before it exercised an explosive effect. This opinion was 

 more particularly supported by the Belgian physicist 

 Melsens, who actually described it by the term " pro- 

 jectile air." The matter was taken up from the point of 

 view of pure physics, and Magnus demonstrated that if 

 a body like a bullet entered water, e.i^. in falling the 

 funnel which the displaced water makes in the axis of the 

 body as soon as that is fully immersed, entangles air, and 

 that it is this air which is carried by the body into the 

 fluid, rather than that any air is forced in in front of 

 the bullet. In answer to Magnus, Larociue invented the 

 following ingenious experiment. Me allnwed a long 

 body, incapable of wholly sinking, to drop into the water, 

 and then found that there was air driven in in front 

 of it ; while, by the nature of the experiment, he had, 

 of course, excluded the possibility of any air following 

 the base of the projectile. 1 have repealed all these ex- 

 periments (employing in Laroque's a slender rod of wood) 

 and found that while his contention that air is driven in 

 front of the bullet is completely substantiated, yet 

 Magnus' observation is so far correct that air is also 



