12 



NATURE 



[Dec. 12, 1878 



word "speed." If in any passage ambiguity lias thus been 

 occasioned — or, as I* would rather say, if anything I have 

 thus said can be mistaken — I shall be glad to hear of it and set 

 it right. 



I must have failed, however, to make my meaning clear to 

 P. G. T. in pp. 194 and 240. If at least he rightly under- 

 stands me, I must leave him to settle with observed facts in one 

 case and with the recognised authorities in the other. 



My account of the earlier experiments of Professors Andrews 

 and Tait was taken, as stated, from a paper by Prof. Ileaton. 

 1'. G. T. ought to know the facts, and I accept his correction. 

 When my article was written, several years ago, the "now 

 received idea " was not yet received. I did not err in calling 

 that theory "beautiful" and "ingeniously conceived "which is 

 now generally accepted. But if I had, it is a less serious mis- 

 take to describe a sound theory as still open to doubt, than to 

 describe a doubtful theory as demonstrated. This the author of 

 the sea-bird theory of comets might remember with advantage. 



Richard A. Pkoctor 



Graphic Granite 



I HAVE been spending some time of late in the examination 

 of the rocks of this district, and was pleasantly surprised, a few 

 weeks back, at finding some well-marked specimens of graphic 

 granite among the waste material raised from Huel Agar Mine. 

 It very closely resembles that found at Portsoy, N.B., but the 

 felspar is grey instead of red. As I am not aware that this 

 interesting rock is known to exist in any other locality in Eng- 

 land, the observation may be worthy of record. 



W. End, Redruth, December 2 Frank 'Johnson 



The Phonograph and Vowel Sounds 

 In the interesting paper on " The Phonograph and Vowel 

 Sounds" (vol. xviii. p. 340, et seq.), the authors remark that 

 although the general results are the same as I have inferred from 

 my own researches, the special numbers expressing the distribu- 

 tion of total intensity of vowel sounds among the partial tones 

 are very different. Perhaps you will have the kindness to com- 

 municate to your readers the following reasons explaining, as I 

 believe, the difterences mentioned above. 



1. The tables given by the authors, which contain the distri- 

 bution not of intensity but of amplitudes, must be altered in a 

 manner readily seen in order to be comparable with my tables, 



2. The marks impressed by the phonograph contain certain 

 peculiarities which, although without influence on the tones 

 spoken from the instrument, remain effective in modifying the 

 form of the curves obtained by mechanically transferring them. 



3. The objective intensity (kinetic energy) determined by the 

 authors is nearly, but not quite, proportional to the subjective 

 intensity (quantity of sensation) which I have measured with 

 the aid of resonators. 



4. As I have observed, the differences of English and German 

 pronunciation cause remarkable differences in the distribution of 

 total intensity of vowel sounds among the partial tones. 



Taking the above points into consideration it will be seen that 

 the differences mentioned by Messrs. Jenkin and Evving appear 

 much smaller. 



Besides I am pleased to notice that the authors, like my- 

 self, consider the flexibility of mouth cavity as important in 

 explaining, where it exists, the characteristic pitch and other 

 properties of vowel sounds. F. Auerbach 



Local Colour-Variation in Lizards 



This subject has recently been very fully discussed by my 

 friend, Dr. Max Braun, assistant in the zoological laboratory of 

 the University of Wiirzburg. His paper, which has especial 

 reference to the lizards of Minorca and of some of the smaller 

 islets of the Balearic group which lie round that island, is 

 entitled " Lacerta Lilfordi und Lacerta muraUs," and will be 

 found in Part I. of the fourth volume of Prof. Semper's 

 "Arbeiten aus dem zoologisch-zootomischen Institut in Wiirz- 

 burg," published in May, 1877. 



Braun refers constantly in this paper to a memoir by J. von 

 Beidraga, entitled " Die Faraglione-Eidech.-e und die Ent- 

 stehung der Farben bei Eidechsen," which was published at 

 Heidelberg in 1876. P. Herberj Carpenter 



Eton College, December 9 



The Rangi of the Mammoth 

 On November 6 Prof. Boyd Dawkins read a paper before the 

 Geological Society on " The Range of the Mammoth in Space 

 and Time." As the professor and several other recent writers 

 have taken it to be proved that Elephas primigenins occurs in 

 pre-glaclalbeds it will, perhaps, be as wall at once to review 

 the evidence. 



Geologists often speak of " pre-glacial beds " when they only 

 mean beds beneath some one boulder clay, perhaps No. 6, or 

 even later in the list given below. The succession is roughly as 

 follows : — 



Upper, Middle, and Lower ol 

 the North of England (?) 



Upper, Middle, and Lower of 

 Lincolnshire, &c. (?) 



Upper, Middle, and Lower of 

 East Anglia, 



Lswer Boulder Clay of the Nor- 

 tolk Coast. 



Pliocene 



6. Hessel Boulder Clay 



Hessel Gravel 



5. Purple Boulder Clay 



Bridlington Crag 



4. Chalky BoiTlder Clay 



Mid -glacial 1 



3. Contorted Drift ' 



Sands ^ 



2. Second Till^ 



Intermediate Beds ^ 



I. FirstTilF 



Arctic Freshwater Beds.^ 



Temperate Freshwater Beds.^ 

 (Land surface.) 



W^eybourn Beds, estuarine, 



including the "Forest Bed."^ ) 



As the loiuer boulder clay of Northwich, in Cheshire, appears 

 to be No. 5 or No. 6, and consequently newer than the upper 

 boulder clay of East Anglia, the molar of E. primigentus found 

 beneath it need not be pre-glacial. The Hertfordshire boulder 

 clay, beneath which Prof. Prestwich found a tooth is, I believe, 

 No. 4. 



In East Anglia I have seen two molars of E. frhnigenius 

 from the contorted drift. No 3 in the list, but it has not yet been 

 found lower. All the specimens said to come from the forest 

 bed have been di-edged or picked up on the beach, and are of 

 no value as evidence. At Bacton, on the Norfolk coast, I dug 

 out a jaw and three teeth of the mammoth from a post- 

 glacial deposit ; if the denudation of the cliffs had proceeded 

 these teeth would have been found on the beacli mixed wi:h 

 those of E. meridionalis . There appears to be one specimen, 

 and one only, found in sitic in the Forest Bed which can with 

 any probability be referred to E. primigentus ; this was found 

 some years ago by Mr. Savin, of (jromer, it has not yet been 

 satisfactorily determined, but from its peculiarity and the differ- 

 ence of opinion about it, it appears certainly not to be the ordinary 

 form. Clement Reid 



Egton Bridge, Yarm, Yorks 



The Bunsen Flame a Sensitive Flame 



It is not generally known, if it has ever been noticed before, 

 that the Bunsen lamp gives a flame sensitive to sounds. A lamp 

 should be chosen which has a tendency to " burn below ; " this 

 may usually be secured by opening the air passages to the utmost 

 and lessening the supply of gas. The flame should burn quietly. 

 My most sensitive flame is four inches high ; the gas at about one 

 inch pressure of water. A smart tap with a penholder on a glass 

 cylinder a yard from the flame causes the characteristic "duck- 

 ing," which is sometimes so energetic as to extinguish the flame 

 or to cause it to burn below. The acute sound of rattling 

 bottles, of a glass rod against a beaker, and many such familiar 

 sounds of the laboratory, are the most effective. This may 

 explain burning below without obvious cause. A tap on a 

 mortar with the pestle twenty feet distant from a well-adjusted 

 flame causes it, and so, often unintentionally, we may have the 

 same result. W. \V. Haldare Gee 



Preston, December 3 



OUR ASTRONOMICAL COLUMN 



Jean Dominique Cassini. — In the course of his ex- 

 amination of the older archives of the Paris Observatory, 

 which had been placed at his disposal with unrestricted 

 permission to make extracts for use in his lunar re- 



' These will be described in the Geol jglcal Survey Memoir on the Crosier 

 Cliffs 





