December i6, 1915] 



NATURE 



425 



LETTERS TO THE EDITOR. 



[The Editor does not hold himself responsible for 

 opinions expressed by his correspondents. Neither 

 can he undertake to return, or to correspond with 

 the xvriters of, rejected manuscripts intended for 

 this or any other part of Nature. No notice is 

 taken of anonymous communications.] 



Pre-Columbian Representations of the Elephant in 

 America. 



When I wrote my letter on this subject to Nature 

 (^November 25, p. 340) I was not aware of the fact that 

 another interpretation of the Copan elephants was 

 being seriously adopted in America. The admission 

 of the proboscidean nature of the sculptures in ques- 

 linn would place those who indulge in speculations as 

 10 the wholly indigenous origin and local evolution of 

 the pre-Columbian civilisation of America in so critical 

 a dilemma that from time to time efforts have been 

 made to discredit the obvious view of regarding them 

 as elephants. In my previous letter I directed atten- 

 tion to the attempts which had been made to convert 

 them into tapirs or tortoises. Certain American 

 ethnologists are now suggesting that the Copan reliefs 

 in question were really intended to represent blue 

 macaws ! 



Ludicrous as this suggestion (Parry, 1893 ; Gordon, 

 iqog; Tozzer and Allen, 1910; and Spinden, "A Study 

 of Maya Art," Memoirs of the Peabody Museum, 1913, 

 p. 79) may seem to those who examine the features 

 of the unmistakable elephant, which I reproduced in 

 my previous letter, the arguments in support of it are 

 not nearly so lacking in cogency as those with which 

 I have already dealt. 



For if the macaw-hypothesis were admitted, it would 

 help to explain the positions of the nostril and eye, 

 the origin of the geometrical pattern around the eye, 

 and, in a vague manner, the presence and form of the 

 trunk (see Gordon, Putnam Anniversary Volume, 1909, 

 pp. 193-95). -^t Copan there is a beautifully modelled 

 and very realistic representation of the macaw. But 

 the very excellence of the portrayal of the macaw is an 

 argument against the contention that the proboscidean 

 animals can also be meant to be pictures of that bird, 

 even in a conventionalised and extremely modified 

 form. When the American artists set about conven- 

 tionalising natural objects, an occupation at which 

 they were past-masters, their methods were vastly 

 different from those which such a hypothesis demands. 

 Moreover, the accurate representation of the Indian 

 elephant's profile, its trunk, tusk, and lower lip, the 

 form of its ear, as well as the turbaned rider and his 

 implement, no less than the distinctively Hindu artistic 

 feeling in the modelling, are entirely fatal to the 

 macaw-hypothesis. 



The representation of a man sitting upon the head 

 is as wholly inappropriate if the beast of burden is a 

 macaw, as it would be in the case of a tapir or a 

 tortoise. 



Nevertheless, this suggestion has served to direct 

 attention to points of special interest and importance, 

 viz., the striking influence exerted by the representa- 

 tion of a well-known creature, the macaw, on the 

 craftsmen who were set the task of modelling the 

 elephant, which to them was an alien and wholly un- 

 known animal. It explains how, in the case of the 

 latter, the sculptor came to mistake the eye for the 

 nostril and the auditory meatus for the eye, and also 

 to employ a particular geometrical design for filling 

 in the area of the auditory pinna. 



In a memoir now in course of preparation I have 

 discussed more fully the extensive literature relating 

 to this elephant-controversy, and considered the 

 problems arising out of it. In particular I have 



NO. 2407, VOL. 96] 



directed attention to a most remarkable confirmation 

 of the identification of these American elephants. The 

 series of beliefs which the ancient population of 

 Mexico associated with Tlaloc, their elephant-headed 

 god of rain, thunder, lightning, and agriculture (and 

 the people of Yucatan with the proboscidean Chac), 

 reproduce with the most amazing exactness the essen- 

 tial elements of the Hindu legends concerning Indra, 

 the god of rain, thunder, and lightning, who was_ also 

 associated with the elephant. Both were associated 

 with the east and with the tops of mountains. Indra's 

 most famous exploit was the slaying of "the snake 

 Vritra, the restralner, who catches and keeps In the 

 clouds the rain that is falling to earth " (Hopkins, 

 "The Religions of India," 1902, p. 94). Tlaloc Is 

 credited with similar performances (Joyce, " Mexican 

 Archaeology," 1914, p. 37). In the Codex Tro-Cor- 

 tesianus Tlaloc is represented treading upon the head 

 of a serpent who Is interposed between the rain the 

 god Is pouring upon the earth (Zeitsch f. Ethnologic, 

 1910, p. 75, Fig. 837 — in my previous letter I wrote 

 "' Archiv " instead of ''Zeitsch."). In the Codex Cortes 

 {op. cit., Fig. 839) the snake is shown coiled to sur- 

 round and retain the water. 



Coincidences of so remarkable a nature cannot be 

 due to chance. They not only confirm the identifica- 

 tion of the elephant-designs in America, but also inci- 

 dentally point to the conclusion that the Hindu god 

 Indra was adopted in Central America with prac- 

 tically all the attributes assigned to him in his 

 Asiatic home. G. Elliot Smith. 



The University of Manchester, December 3. 



Electric Conductivity of the Atmosphere. 



One of the Notes in Nature of November 25 (p. 351) 

 begins with the following sentence : — "The theory that 

 the upper layers of the atmosphere are ionised and 

 therefore conduct electricity, first enunciated by the 

 late Prof. FItzGerald in 1893, • • •" I^ is a good rule, 

 to which I have always hitherto adhered, not to raise 

 questions of priority, but In this particular case a 

 point of general interest in scientific history Is involved, 

 and a claim made which postpones the enunciation of 

 a fruitful Idea by sLx years. In the paper presented to 

 the Royal Society In May, 1887 (Proc. Roy. Soc, vol. 

 xlil., p. 371), I proved by exj>eriment that the gas in 

 a vessel through which an electric discharge passed 

 became a conductor even In regions of the vessel re- 

 mote from the discharge, and at the end of the paper 

 the application of this result to the conductivity of the 

 regions of the atmosphere afl"ected by thunderstorms 

 and aurorae Is quite clearly expressed. 



On first reading the paragraph in Nature, I thought 

 that the writer wished to lay stress on the word 

 "ionlsation," an expression I avoided for reasons 

 which I need not enter into here, but on referring to 

 FitzGerald's Collected Papers I find that in the only 

 paper dated 1893 which deals with the subject the 

 word is not made use of, and further, that the author 

 does not claim any novelty for the idea, but refers to 

 the conductivity of the atmosphere as an established 

 fact. The term " ionlsation " was first used by .^rr- 

 henius In describing experiments similar to mine, 

 made independently but published somewhat later. 



To avoid misunderstandings, I may add that In all 

 the experiments above referred to the carriers of 

 electricity, or "ions," as we should now call them, 

 were considered to have molecular dimensions, as in 

 the case of electrolytes. The idea of " corpuscles " of 

 much smaller masses, afterwards introduced with such 

 important results by Sir Joseph Thomson, belongs to 

 a diff'erent chapter of the history of the subject. 



Arthur Schuster, 



Yeldall, Twyford, Berks, November 29, 



