Nov. 28, 1878] 



NATURE 



73 



consequence of what appears to have been a chronic disease of 

 the eyes, the poet lost his sight at the early age of about 32 or 34 

 years, and that he, once at least, styles himself a downright blind 

 man, in his Plynm to Delian Apollo, ver. 169 — 73, which derives 

 no mean authenticity from being so pointedly quoted by 

 Thucydides, III., 104, and which runs thus : — 



.... 6w6t( Kiv Tis (-Kix^ovltav dvOpdirccy 

 iyOdS' dffipTjTat ^fiiftos raXairtlpios 4\d<iv' 

 w Kovpai, rls 5' ifjiiiiv dvi)p tjSkttos aoiBaiy 

 (vd 'S( vwXuTai, Kol rtcj) repirfffOe fid\tffTa ; 

 vfi(7i 8' *§ fM\a irda-ai tnroKpivaaff eu<priaci)s' 

 TvpXhs dvTJp, oIk(7 Se X(ai fvt traifcaXofffay, 

 rod Tatrcu nfT6iri<T0fy dpi<TTevovffiv doiiai. 

 If some day an earthbom man, a wayfaring stranger. 

 Asks you the name of whom best you like of all the minstrels 



you know. 

 Whose songs are, oh lasses, the most delightful to you, 

 Oh, then, unanimously, siirely, you answer : 

 It is the blind man who dwells in the rocky island of Chios, 

 His songs are to us by far the sweetest of all. 

 I need not add, as a further argument, that Homer frequently 

 ■was alluded to as the blind and humpbacked man, 6 Kv<p6s koI 

 rwpxts derip,^ and it seems to me trifling to qualify, or mitigate, 

 the racy juxtaposition of the two epithets. 



To what extent colour hallucinations, so frequent in connection 

 with certain forms of blindness, may possibly have impaired the 

 poet's imaginative faculties with regard to the varying hues and 

 shades of colour, it would be for the present, from want, for 

 obvious reasons, of similar observations, difficult to settle. How- 

 ever, I cannot but think that what by some so recently has been 

 called Homer's colour-blindness may be the natural consequence, 

 on the one hand, of the increasing dinmess of his recollections 

 as well as owing to these optical hallucinations, and finally, to the 

 defective chromatic terminology of his time. The following are 

 some of the Greek and Latin authors who, together with 

 Herodotus, aver and enlarge upon the blindness of Homer : — 

 Plutarch, Vita Horn. 12 ; Thucyd., III. 104 ; Pausan., II. 32^ 3 J 

 III. 4, 22 ; Lycophron, Cassandra, 422 ; Aristot., Orat., L. p. 703 ; 

 Cicero, Tuscul, V. 39, 



I refrain from discussing the question whether, from a physio- 

 logical point of view, such a profound fimctional perturbation as 

 is involved in the term of colour-blindness, viz. , deficiency in the 

 perception of any plmrality of colours in the spectrum, would 

 Bot seem to be symptomatical of most momentous organic dis- 

 turbances in the nervous apparatus of the eye, generally con- 

 ducive to the most hopeless forms of blindness. 



Scientific Club J. Hersciiel 



In reading Mr. Pole's article on Homer's sensations of colour, 

 there is one point which seemed to me to call for explanation. 

 Mr. Pole says that in the solar spectrum he sees only two colours, 

 blue and yellow, and that the red space appears to him yellow. 

 From this one would naturally infer that the whole of the spec- 

 trum visible to ordinary persons is visible to him also, but that 

 it presents only these two colours, which graduate :into one 

 another without any break, and that the greea space appears as 

 yellow. And with a colour-blind person who has allowed 

 me to test his capabilities, I found this actually to be the 

 case. Bat later on Mr, Pole says that pin-e red and pure green 

 appear to him not yellow but grey. I would wish, then, to ask 

 Mr. Pole whether the spectrum presents to his vision, in place of 

 the green, a neutral space or an interval of darkness? In other 

 words, have the rays of that particular refrangibUity no action 

 at all upon his retina, or is it that they have no action peculiar to 



* The very word of O/xjjpos signified " blind " in the vernacular idiom of 

 K''M''/i or Cumae, one of the jEolian colonies in Asia Minor, where he lived 

 for some time, and, as will be shown ancn, accidentally came by the name 

 of Homer, h:s original name being Melesigenes, from his happening to be 

 bom on the banks of the small river Meles, which flows by Smyrna and runs 

 into the Smymian sLaus. 



One day, pointing out how much of the poet's glory was certain to redound 

 to their own city's glory, if the poet oould be induced to seitle among them, 

 It was proposed to the people of Cumse to provide during his lifetime for his 

 wants, at the public expense, when somebody explained that such a resolution 

 ■would betanumouQt to invitingallsortsofblind,"OM'jpoj, and useless, people 

 to their city, whereupon the prop^osal dropped. But it seems that, hence- 

 forth, the poet went by the name of Homer: — 



Opjipos liriKparriae rw Vli\t\aiy(Vfi dirb Trfs avfi.<f>opj]s ; 01 y&p 

 Kv^iatot ToCs rixpXois "Ofiripovs \4yovaty. "Clare vpSrepov ofo/xa- 

 ioftfvov avTov yifK-rjffiyfytoSjTOhTO yfy4a6anovvoua''0,urjpos. 



Herodjt.' Halic, vita Hom., 2, 13. 



themselves, but simply produce the general effect of light ? In 

 either case the phenomenon seems more anomalous than if he 

 saw all colours as colours, though he could only class them under 

 two heads. To take a familiar analogy, it is as if a man 

 should be perfectly able to distinguish the pitch of notes at either 

 end of the scale, but the notes between should either not affect 

 the auditory nerve at all, or should affect it simply as noi-e. 

 Pembroke College, Oxford Frank Podmore 



Anthropometry 



As I have stated in the preface that my object in publishing 

 my "Manual of Anthropometry" is to invite criticism with a 

 view to perfecting the anthropometrical chart which it contains, 

 and which forms its chief feature, I may be excused for referring 

 to the notice of the work which appears in Nature, vol. xix. 

 p. 29. The reviewer objects to the large nimiber of measure- 

 ments given in the chart, but he has overlooked my statement 

 that many of them are of a .secondary character, and that I leave 

 the student liberty to select the measurements which best .'uit his 

 purpose, requiring only of him that they shall be made and 

 recorded in a uniform manner, and thus become the common 

 property of statisticians. Anthropometry can make no progress 

 as a science, so long as observers are at liberty to make .the same 

 nominal measurement of the body in four or five different ways, 

 as is the case, for instance, with chest-girths. 



I may add that my manual was not written for the three or 

 fomr individuals in this coimtry who have mastered the "theory 

 of human proportions " as a mathematical curiosity, but for army 

 surgeons, busy medical men, schoolmasters, and others who are 

 much more concerned with actual facts than theories of 

 probabilities. Charles Roberts 



Bolton Row, W. 



Di^visibility of Electric Light 



In all communications on this subject in Nature and else- 

 where, the division of light is considered only with reference to 

 parallel circuits, and this natmrally cames great loss of light by 

 the law that heating is proportional to the square of the current. 

 But in electric circuits their resistance has alwajs to be con- 

 sidered ; and if two lamps are taken parallel, only half the 

 resistance of the one lamp is obtained, and such resistance can 

 be obtained by taking two parallel circuits of two lamps in series 

 in each ; the light obtained then is one quarter in each lamp, as 

 half the cturent is flowing through each circuit, and as fovur 

 quarters make a whole, no loss of light is caused by division in 

 such a method of one ciurent to any number of lamps. There 

 are certainly practical difficulties in the way of burning lamps in 

 series, though these are greatly diminished if incandescent wire 

 is u-ed as the light-emitting source. However, there is no 

 inherent reason why the electric light should be wasteful in 

 division, as is describedby Mr. Trant. F. Jacob 



Verification of Pervouchine's Statements regarding the 

 Divisibility of Certain Numbers 



The statements of Pervouchine, reported in some recent 

 numbers of Nature, are equivalent to the following : — That the 

 2^'^ power of 16 is less by i than some multiple of 7 x 2^* -f i ; 

 and the 2^^ power of 16 is less by i than some multiple of 

 5 X 2-5 -f I. 



Let r„ be the remainder after dividing the 2^ power of 16 by 

 one of the above divisors. Then since the 2'^+^ power of 16 is 

 the square of the 2° power, r„+j differs from the square of r„ by 

 a multiple of the divisor ; or r„ ^ ^ is the remainder arising from 

 the division of the square of r„. 



Use for the work the scale whose radix is 16. In this scale 

 the above divisors are 



I 12 o o I and 10 o o o o o i. 

 In the first ca^e, calculating on the plan indicated, we find the 

 remainders. 



r3 = - 5249 



r4=-iii64i3 

 r- — - 5 9 10 6 



rg = - 15 10 4 13 



rj — - I o 10 15 



rg = - I ID 8 15 15 

 r» = - 14 5 2 II 



r,n = - 1 



