5i8 



NATURE 



[October 28, 1909 



felloes of a wheel. This derivation corresponds with 

 Digges' description of the instrument. 



E. H. V. Melvill. 

 203 and 204 New Stock Exchange Buildings, 

 Johannesburg, Transvaal, September 37. 



A Supposed New Mineral. 



A SPECIMEN of a mineral, forming portion of a mass 

 stated to have been found in the basalt of Co. .Antrim, was 

 recently sent for identification to the office of the Geological 

 Survey of Ireland by Mr. S. B. Wilkinson, the senior 

 geologist, to whom it was handed by the finder. .As it 

 presents some peculiar features, and appears to be new to 

 science, we take this opportunitv of recording its occurrence. 

 The complete examination of the mineral will necessarily 

 occupy some time. 



The mineral strongly resembles cobaltite in appearance. 

 Its lustre is metallic, hardness about six. It breaks with 

 a surface which under the microscope shows a finely 

 conchoidal structure. When etched with an acid a crystal- 

 line structure becomes apparent ; it is fusible with difficulty, 

 but in the oxyhydrogen flame it melts without apparent 

 alteration. Heated in a closed tube it does not yield any 

 sublimate. 



When the mineral is powdered, or even its surface 

 scratched, it emits an odour like that of acetylene prepared 

 from commercial calcium carbide. Hydrofluoric acid dis- 

 solves the mineral, the other acids have little effect upon 

 it. while it is readily decomposed by fusion with the alkaline 

 hydroxides. 



A preliminary chemical analysis shows that the mineral 

 is essentially a compound of iron, silicon, and carbon. 



Ricn.ARD J. Moss. 

 Henry J. Seymour. 



Ijaboratory, Royal Dublin Society, October 20. 



The Pitcairn Islanders. 



When reading Mr. M. J. NicoU's " Three Voyages of 

 a Naturalist " a short time ago, I came across the follow- 

 ing passage on p. 211 in the chapter on Pitcairn Island : — 



" The older people, as well as the younger children of 

 Pitcairn, have fair complexions, but the people of from 

 thirty to fifty years of age are quite as dark as the average 

 Polynesian. It appears from this that the Pitcairners 

 resemble their ancestors, the ' Bounty ' mutineers, every 

 alternate generation." 



It may be remembered that in 1790 nine mutineers, 

 six native men, and twelve native women sailed from 

 Tahiti to Pitcairn ; the native women killed the native 

 men, and by iSoo only one British sailor was left, from 

 whom the present inhabitants are descended. 



Just before the above extract Mr. Nicoll tells us that 

 " Lord Crawford paid a visit to the two oldest inhabitants 

 . . . both of whom are grandchildren of the original 

 mutineers." So we see that the grandchildren and the great- 

 great-grandchildren were fair, resembling the British men, 

 while the great-grandchildren were dark, resembling the 

 native women. That is to say, that Fj and F^ generations 

 resembled the cJ P,, while F, generation resembled the 



9 P,- 



These facts struck me as being particularly interesting, 

 as experiments of this nature in human heredity are 

 difficult to obtain. Perhaps some " Mendelist " may be 

 able to use or explain them. C. B. Williams. 



Clare College, Cambridge, October 14. 



The Auroral Display of October 18. 



I WAS very much interested in Mr. Harcourt-Bath's letter 

 describing an auroral display which he saw from the 

 Cotteswold Hills. 



From West Kirby Hill, on the Wirral, I noticed a 

 luminous band low down on the horizon, with upward 

 streamers and " a detached, red, cloud-like portion " rather 

 north of west. 



NO. 2087, VOL. 81] 



What struck my attention, however, was that behind 

 this red patch there were dark clouds, at no great altitude, 

 faintly illuminated on the underside by the aurora. 



As the red colour outlasted the streamers by several 

 minutes, I was brought to the conclusion that it was in- 

 dependent of the auroral display. 



However, in view of Mr. Harcourt-Bath's letter, I am 

 led to ask you if observers have ever thought that an aurora 

 could be comparatively close to the earth, and not of 

 necessity in the " highly rarefied layers of the air "? 



Ernest J. Baty. 



" Nunclose, " West Kirby, Cheshire. 



It may interest Mr. Harcourt-Bath to know that the 

 auroral display of October iS was strikingly visible at 

 Dudley. At 9.15 p.m. there were six or more broad beams 

 of white light of unequal lengths and widths. These sprang 

 normally from a broad circular arc resembling a " Milky 

 Way " in luminosity and a broad rainbow in shape and 

 size. 



The central vertical beam was the brightest, widest, and 

 longest, extending vertically about 45°, but not terminating 

 definitely; it was about 10° W. of N. 



The broad arched base appeared to cross through Ursa 

 Major, the vertex being about 20° above the horizon, and 

 was not uniformly bright. About 9.30 p.m. the left-hand 

 (W. of N.) half of the base became a soft violet light ; 

 the right-hand portion remained white, but grew fainter. 



W. Austin Morley. 



14 Park Road, Dudley, October 26. 



The Occurrence in India of the Pappataci Fly (Phleho- 

 tovtus papatasii). 



The ro/c' nowadays assigned to PJdehotoDiiis papatasii in 

 the transmission of a certain type of fever (see " Das 

 Pappatacifieber," 1909, by Drs. Doerr, Franz and Taussig) 

 makes the geographical distribution of this little fly a 

 matter of practical importance. It is therefore interesting 

 to note that this species is common in certain parts of 

 northern India. Some time ago Mr. F. M. Howlett, 

 second imperial entomologist, sent me specimens from 

 Rawalpindi, in the Punjab, and Pusa, in Bihar, which I 

 identified as belonging to a species allied to P. papatasii. 

 Through the kindness of Dr. J. H. Ashworth I have now 

 been able to compare some of these specimens with Euro- 

 pean examples of P. papatasii in the zoological laboratory 

 of the University of Edinburgh. I can find no difference 

 except that the Indian specimens are perhaps slightly 

 smaller than the European ones. The former agree as 

 regards venation, genitalia, &c., with Grassi's beautiful 

 figures (" Ricerche sui Flebotomi," 1907). 



In addition to P. papatasii, six Indian species of Plilebo- 

 tomus are now represented in the collection of the Indian 

 Museum. They will be fully described shortly. 



N. Annandale. 



The Mansfield Automatic Water-finder. 



With reference to Mr. A. A. Campbell Swinton's letter 

 in regard to Mansfield's water-finder, which appears in 

 Nature of October 14, it may be of interest to state that I 

 made inquiries from Messrs. Mansfield and Co. in May, 

 1908, asking for the names of the " leading scientists and 

 engineers " who, as they stated, " vouched for the 

 successful application of the invention " ; they did not 

 send me any names, but allowed a friend of mine in Liver- 

 pool to call to see the documents. One was from an 

 architect in Liverpool, another from a firm of well-borers, 

 and there were some foreign ones, but none were produced 

 that were signed by persons whom I should describe as 

 " leading scientists and engineers." 



I may add that I expressed my willingness to test their 

 instrument, but one was not placed at my disposal. 



J. Wertheimer. 



Merchant \"enturers' Technical College, Bristol, 

 October 20. 



