666 



NA TURE 



[November 18, 1922 



healing properties have, says Prof. Barrois, from the 

 most remote antiquity, attracted patients suffering 

 from eczema, arthritis of every kind, and other 

 afflictions. But, with regard to Prof. Gudger's 

 ingenious explanation of the miraculous draught of 

 fishes, coupled with Lortet's description of the 

 behaviour of grebes over a shoal of large Chromids 

 and Canon Tristram's account of their dorsal fins 

 as seen at the surface, surely the wonder is that 

 experienced fishermen like St. Peter should have 

 needed outside assistance, let alone superhuman aid, 

 as is implied in the narrative of St. John's Gospel. 



T. R. R. S. 

 Tunbridge Wells, October 30. 



In the passage from Lortet's work on the Lake of 

 Tiberias, quoted in Prof. Gudger's interesting letter 

 in Natur] ol October 28, p. 572, the scientific title 

 of the crested grebe is given as Podiceps cristatus. 

 This misrendering of the true name of the genus 

 Podicipes may be traced, I think, to Yarrell, for it 

 appears in his " History of British Birds," published 

 in 1845. Yarrell was not a classical scholar; but it is 

 strange that the late Lord Lilford should have slipped 

 into the same error in his splendid " Coloured Figures 

 of British Birds. " The difference in form is important, 

 because Podiceps, if it means anything, means " rump- 

 headed " ; whereas in coining the word Podicipes, 

 meaning " rump-footed," Linnaeus indicated the 

 posterior position of the feet so characteristic of 

 the genus. Herbert Maxwell. 



Monreith, \Y ha uphill, 

 Wigtownshire. 



Prof. E. W. Gudger's letter on this subject in 

 Nature of October 28, p. 573, is interesting from 

 the natural history point of view, but it misses the 

 most suggestive point in the narrative. That point 

 is the number — one hundred and fifty and three. 

 What is the meaning of this very definite figure ? 

 It will scarcely be contended that the number is 

 merely the simple statement of a historic fact — that 

 the fishes caught did actually number one hundred 

 and fifty and three, neither more nor less ! The 

 naive literalism of such an explanation is totally blind 

 to the true significance of the story. 



Obviouslv, the story is a parable. The lake of 

 Gennesaret is the world. The fishes are the souls 

 of men. The net that is not broken is the Church. 

 And the number ? That is a problem, but an explana- 

 tion I heard given in a sermon by my father, the 

 late Rev. R. B. Drummond, of Edinburgh, seems 

 to meet the case. Where he found the solution 

 I do not know. It was not original. 



The Jews, as is well known, attached a mysterious 

 significance to numbers, and if they met a definite 

 number like this, they would not pass it by unheeding, 

 but would try to discover its meaning. Well now, 

 this number is what is called the perfection of the 

 number 17 ; that is to say, it is the number arrived 

 at by adding all the consecutive numbers from 

 1 to 17 inclusive. And the number 17 itself is the 

 sum of the two sacred numbers 7 and 10. These 

 again (here I am a little vague as to why) stand 

 respectively for the Jews and the Gentiles. Hence 

 the story means that the net of the Church is able, 

 without breaking, to gather together not only, as 

 some contended, Jews and those who became Jews, 

 but all sorts and conditions of men of every race 

 and tribe. W. B. Drummond. 



Baldovan Institution, by Dundee. 

 November 1 . 



Prof. Gudger's communication under this heading 

 in Nature for October 28, p. 572, has brought back 

 to me a vivid recollection of a fishing incident in the 

 north-west of Ireland. About a dozen years ago I 

 spent a week-end at BalTina, County Mayo, and as 

 the express to Dublin did not leave until after mid- 

 day, I devoted Monday forenoon to a ramble along 

 the banks of the Mov river. Observing several 

 men, with a boat and draw-net, making a succession 

 of fruitless attempts to land fish, I crossed the river 

 and made my way to them. It was true — they had 

 toiled and had caught nothing. They were putting 

 out to make another attempt, and I offered them 

 five shillings for the next haul. They declined. 

 The net was hauled in, and there was not a scrap of 

 anything in it. They put off again, and I repeated 

 my offer, which was rejected, and the net came in 

 empty, as before. With all their futile endeavours 

 the men were not in the least put out. Calmly the 

 boat and net were again got ready, and I was told 

 it would be no use offering to buy the haul. When 

 the net was landed it was found to have brought in 

 one little fish — a sprat in size ! Apparently this was 

 looked upon as a good sign — a command to try again, 

 for, still undaunted, the men persevered — they rowed 

 off cheerfully, let out the net, then returned to 

 shore and hauled at the net, but evidently it was 

 harder work than on any previous occasion. When 

 the operation was completed, hundreds — the men said 

 eleven hundred — salmon had been landed ! A school 

 from the sea had come up on the rising tide. 



Hy. Harrii s. 



October 28. 



On the Reality of Nerve Energy. 



I have only to-day seen Dr. Adrian's letter of 

 September 30 in which he states with great clearness 

 the present-day physical explanation of the nature 

 and transmission of the nerve impulse. 



It seems to me that it is the relation of this nerve 

 impulse to nerve energy that stands in need of elucida- 

 tion. My present concern is not so much to recom- 

 mend the more extensive use of the term nerve 

 energy as to make sure that when physiological or 

 medical writers use it, we shall have some more 

 ,m 1 urate notion of what they mean by it. Evidently, 

 from what Dr. Adrian says, sometimes they mean 

 mental energy. Surely mental energy is not what is 

 meant in the following paragraph, " In defalcation, 

 when all the nerve energy of the cord is directed 

 into one channel ..." (Yerdon, "Angina Pectoris," 

 Brighton, 1920, p. 357). The late Sir William Osier 

 wrote : " An organisation which is defective in what, for 

 wan! ol a better term, we must call nerve force . . ." 

 (" Principles of .Medicine," 1895, p. 1032). 



Prof. Halliburton, in reviewing von Monakow's 

 " Die Lokalisation im Grosshirn " (Physiol Abst., Nov. 

 and Dec. 1918), thus expressed himself, " The intro- 

 duction of a change in the quantity of nervous energy 

 (Hughling's Jackson) passing over a given system of 

 I ondui 1 ion paths ..." In his "Text-book of 

 Physiology" (London, Churchill, 1912, p. 1211), 

 Prof. Starling wrote: " During the second stage (oi 

 asphyxia) there is a discharge of nerve energy which 

 spreads throughout the whole central nervous 

 system, beginning in the Bulbar Centres . . ." In 

 none of these quotations is it a synonym for mental 

 energy, unless, perhaps, we except Osier's use of it. 



(To recognise " mental energy as a real existence 

 in the sense of being a vera causa, of neural processes 

 is. I believe, necessary, but it involves grave diffi- 

 culties both in psychology and metaphysii - 



The authors just quoted are surely not indulging 



NO. 2768, VOL. I io] 



