3r 



NATURE 



\Nov. 13, 1879 



This preliminary philological question being thus irrefragably 

 settled, I wish to bring to the knowledge of English and 

 western astronomers the fact that, though the zodiacal light was 

 first distinctly noticed in England in 166 1, and named in France 

 by Cassini, in about 16S3, the "false dawn" was known to the 

 Arabians in the days of Muhammad, who is said by the com- 

 mentators in the 183rd verse of Chap. II. of the-Qur'an, to have 

 there legislated on the subject as follows, when he instituted the 

 diurnal fast of the Ramazan in the second year of the Hijra 

 (a.d. 624) : 



"And eat and drink until the lighter streak of the dawn shall 

 become distinguishable unto you from the darker streak." 



Commentators, and, after them, the most highly esteemed 

 Arabic dictionary, the Sihah of Jawhari, who died in A. H. 

 397 (a.d. 1006) explains the expression " the lighter streak," as 

 meaning "the true dawn," and, "the darker streak" as signi- 

 fying "the false dawn." 



Here, then, is incontrovertible proof that the zodiacal light, 

 under its Arabic name of "the false dawn" was explicitly 

 mentioned 650 years, and implicitly, 1,000 and odd years, before 

 western observers had noticed the phenomenon. This is a 

 point deserving special consideration by all who may in future 

 write a history of the progress of discovery in respect to the 

 zodiacal light. To how much older a time than that of 

 Muhammad, a knowledge of the light may be hereafter traced, 

 is a question that I leave with confidence to those who so fruit- 

 fully investigate the fragmentary records of antiquity. I should 

 imagine that no one will suppose Muhammad was the first to 

 take notice of an appearance that is, at times, much brighter than 

 the " milky way." 



Another suggestion has also arisen in my mind, of a far wider 

 interest, in connection with my discovery. It is this : — 



Modern western Sanskrit scholars have inclined to the idea 

 that the high plateau of Pamir, which separates Chinese from 

 Independent Tartary, and the Indus from the Jaxartes, was the 

 primeval cradle of the whole Aryan race. Physically and 

 historically, this hypothesis seems to be utterly untenable, though 

 mv reasons would be out of place here. The zodiacal light 

 would appear to confirm my objection. 



From the latitude of Pamir, the zodiacal light is a very 

 conspicuous object there, and sure to be noticed by a nation of 

 shepherds, nomads warriors, and commercial caravan travellers. 

 Had the various Aryan races all come from Pamir, they would 

 have brought thence a knowledge of the zodiacal light, as they 

 all brought the word " yoke " with them from the land whence 

 they radiated. How comes it, then, that in ancient times as in 

 modern, no Aryan, not even after Alexander had nearly reached 

 Pamir, and the Ptolemies had reigned in Egypt for centuries, 

 ever observed or mentioned this phenomenon? My conjectural 

 answer is this : The Aryan race came originally from a northern 

 land, where the zodiacal light is rarely and but dimly visible, 

 radiating from thence as they have done all through the historical 

 period, and as their rearmost representatives, the Slavs, are 

 persistently striving to radiate still to climes more favoured than 

 their own. J. W. Redhouse 



London, November 5 



The Caudal Disk 



The following may throw some light on the use of the caudal 

 disk possessed by many of the Uropeltidae (vide Nature, vol. 

 xx. p. 538):- 



When in the Wynaad, in September, 1875, I captured, at the 

 foot of the Nilgiri Hills, a Silybura, referred, I think, by Col. 

 Beddome to the species, Nilgiriensis. This snake I took down 

 to Mangalore, and kept alive until the succeeding March, when 

 it was unfortunately killed by ants. When caught it was 

 working its w ay through grass by the road-side, and made violent 

 efforts to escape, striking my hand repeatedly with the pointed 

 terminal scales, by throwing back its tail. I am uncertain 

 whether to view this action as defensive or not. It may have 

 been the result of the snake's struggles, but it is noticeable that 

 the movement was vertical and not horizontal. 



I had but few opportunities of investigating the matter, for in 

 a few days the snake became so used to being handled that it 

 would make no efforts to escape. 



It was kept in a box filled with earth to the depth of some six 

 inches, and during day-time never was to be seen, but at night 

 came to the surface regularly, and was then much less sluggish 

 than in the day. When taken out of the earth, it would at once 



commence to bury itself by forcing its pointed snout downwards, 

 and alternately expanding and contracting the thick anterior 

 portion of the body. The motion was exactly that of a worm, 

 and the posterior portion of the body and the tail were dragged 

 slowly after by longitudinal contraction, and were not actively 

 used. During the burrowing process there were occasional 

 pauses of that part of the body above ground, but from the 

 movements of the earth it was evident that the snake was still 

 progressing. So sensitive was the skin that the gentlest breath 

 would hasten the withdrawal of the body, but so soon as the 

 caudal disk was level with the surface the snake would retain it 

 in that position for a long time, sometimes half an hour and 

 more. The numerous keels on the scales of the disk carried a 

 certain amount of earth ; the disk invariably remained in the 

 same plane as the ground's surface, exactly filling the hole, and 

 it was therefore almost impossible to detect the snake, without 

 close examination. 



These facts suggested to me the idea of the disk being pro- 

 tective, and I therefore, on numerous occasions, unearthed the 

 snake and watched it burrow, always with the same result — the 

 steady withdrawal of the sensitive portion of the body, and the 

 retention of the disk at the surface for a longer or shorter 

 period. 



I do not know what are the chief enemies of Uropeltidoe, but 

 possibly certain carnivorous birds prey on them. If so, it is 

 conceivable that the earth-covered disk would secure the snake 

 and its hole from observation, until the head had worked suffi- 

 ciently far underground to admit of the tail being at once with- 

 drawn, beyond reach of beak or claw. This is quite possible 

 from the power these snakes possess of extending themselves, a 

 power well displayed if one of them be held firmly in both 

 hands. E. H. Pringle 



P. andO. S.S. Pekitt, Gibraltar, October 



Intellect in Brutes 



The Duke of Argyll in his "Reign of Law" was, I think, 

 the first who promulgated the dictum that man is the only tool- 

 making animal. As far as I can ascertain, this assertion is 

 admitted by developmentists, yet it is undoubtedly true that the 

 Indian elephant makes two implements, or forms and alters cer- 

 tain things so as to adapt them specially to fulfil definite purposes, 

 for which, unaltered, they would not be suitable. 



One evening soon after my arrival in Eastern Asam, and 

 while the five elephants were as usual being fed opposite the 

 Bungalow, I observed a young and lately caught one step up to 

 a bamboo-stake fence and quietly pull one of the stakes up. 

 Placing it under foot, it broke a piece off with the trunk, and 

 after lifting it to its mouth, threw it away. It repeated this 

 twice or thrice, and then drew another stake and began again. . 

 Seeing that the bamboo was old and dry, I asked the reason of 

 this, and was told to wait and see what it would do. At last it 

 seemed to get a piece that suited, and holding it in the trunk 

 firmly, and stepping the left fore-leg well iorward, passed the 

 piece of bamboo under the armpit, so to speak, and began to 

 scratch with some force. My surprise reached its climax when 

 I saw a large elephant leech fall on the ground, quite six inches 

 long and thick as one's finger, and which, from its position, 

 could not easily be detached without this scraper, or scratch, 

 which was deliberately made by the elephant. I subsequently 

 found that it was a common occurrence. Leech-scrapers are 

 used by every elephant daily. 



On another occasion, when travelling at a time of year when 

 the large flies are so tormenting to an elephant, I noticed that 

 the one I rode had no fan or v. isp to beat them off with. The 

 mahout, at my order, slackened pace and allowed her to go to 

 the side of the road, where for some moments she moved along 

 rummaging the smaller jungle on the bank ; at last she came to 

 a cluster of young shoots well branched, and after feeling among 

 them, and selecting one, raised her trunk and neatly stripped 

 down the stem, taking off all the lower branches and leaving a 

 fine bunch on top. She deliberately cleaned it down several 

 times, and then laying hold at the lower end broke off a beauti- 

 ful fan or switch about five feet long, handle included. With 

 this she kept the flies at bay as we went along, flapping them 

 off on each side every now and then. 



Say what we may, these are both really bond fide implements, 

 each intelligently made for a definite purpose. 



S. E. Peal 



