532 



NA TURE 



\_Ap7-ii'6, 1886 



to the hill-tribes in the mountainous region to the north 

 of Burma, and especially between Bahmo and Momien. 

 These call themselves by many different names, Chyens, 

 Kyavvs, Paloungs, Khamis, Mros, &c., but a closer 

 examination of dialects, and especially of traditions and 

 customs, proves, says Mr. Scott, that they are merely 

 waifs and strays from the four main stocks, Burmese, 

 Peguan, Karenns, and Shans. The Salones of the 

 Mergui archipelago, some of the Arakan hill-tribes, and 

 the notorious Kachyens in the north, are apparently 

 exceptions, but all the others belong to one or other of 

 these four families. The Kachyens just mentioned are 

 so called by the Burmese ; they call themselves Singpho, 

 or Singpaw, which means simply " men." Ethnologi- 

 cally they are a branch of the Singphos proper, who 

 inhabit the northern Assam hills, and are better known 

 to us by their local names of Gdros and Nagas. Such at 

 least is Mr. Scott's account of them ; but it is quite clear 

 that the last word has yet to be said by ethnologists 

 about these and other tribes adjoining our new territory. 

 The last pages of the volume are devoted to an account 

 of the habits, manners, superstitions, &c., of these hill- 

 tribes. The writer would probably be the last to expect 

 a very high position for this volume as one of original 

 research or information ; but he may fairly claim to ha\e 

 performed a task of much usefulness and interest in a 

 thorough and workmanlike manner. He has placed 

 within easy reach of his countrymen sound and accurate 

 information about a region for the peace, order, and 

 good government of which they have now assumed the 

 responsibility ; and Mr. Scott's own previous writings are 

 mainly responsible for having deprived part at least of 

 the present book of the merit of originality likewise. 



Marvels of Animal Life. By Charles Frederick Holder. 



(London : Sampson Low, Marston, and Co., 1886.) 

 The author, during a long residence among coral 

 reefs somewhere on " our southern border " — we have 

 failed to find exactly where — studied very diligently the 

 various forms of marine life abounding in such places, 

 and he seems to have been attracted more especially to 

 the study of the fishes. From the interesting records of 

 these observations to be found in this little volume there 

 can be no doubt that Mr. C. F. Holder has been a close 

 and intelligent student of nature, and he has grouped the 

 observations of others with his own in a manner to make 

 the record fairly interesting reading to a specialist. To 

 the wider field of young students some of the escapes 

 from whales and swordfish will prove even exciting read- 

 ing, while, so far as we can judge, none of the chapters 

 conve)' erroneous or exaggerated views of the marvels of 

 animal life. The illustrations, of which there are thirty- 

 one, in the form of plates, are often rather sensational, 

 and the majority of them would hardly be claimed as 

 after nature. The work is sure to be popular, from the 

 very novelty of the subjects about which it treats. 



LETTERS TO THE EDITOR 



[ 1 he Editor does not hold himself responsible for opinions expressed 

 bv his correspondents. Neither can he undertake to return, 

 or to correspond with the writers of, rejected manuscripts. 

 No notice is taken of anonymous communications, 



\The Editor urgently requests correspondents to keep their letters 

 as short as possible. The pressure on his space is so great 

 that it is impossible otherwise to insure the appearance even 

 of communications co7ttaininginteresting and novel facts.^ 



Integer Numbers of the First Centenary, satisfying the 

 Equation A- = B^ + C 

 I HAVE sonielinies wished to refer to the principal integer 

 numbers which s.itisfy the equations A" = B- + C-, and I have 

 computed all in which the leading numbers rise to and slightly 

 pass the value 100. Tcrhaps they may interest some of the 

 readers of Nature. 



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<< 



White House, Greenwich, March 31 



0° 



Airy 



The Sunrise Shadow of Adam's Peak, Ceylon 



Some of the phenomena of the shadow of Adam's Peak in 

 the early morning have been remarked by almost every traveller 

 who has visited this island. The mountain rises to a height of 

 7352 feet as an isolated cone projecting more than 1000 feet 

 above the main ridge to which it belongs. The appearance 

 which has excited so much comment is that just after sunrise the 

 shadow of the Peak seems to rise up in front of the spectator, 

 and then suddenly either to disappear or fall down to the earth. 



Various suggestions have been made as to the source of this 

 curious shadow ; among others one, which was published in the 

 Phil. Mag., August 1876, that attributed the rise of the shadow 

 to a kind of mirage effect, on the supposition that the air over 

 the low country was much hotter than on the Peak top. 



I determined to attempt the disco . ery of the true nature of 

 this appearance, and was fortunate to see it under circumstances 

 which left no doubt as to the real origin. Through the courtesy 

 and hospitality of Mr. T. N. Christie, of St. Andrew's Planta- 

 tion, 1 was able to pass the night on the summit, and to carry 

 up a few necessaiy instruments. 



The morning broke in a very unpromising manner. Heavy 

 clouds lay all about, lightning flickered over a dark bank to the 

 right of the rising sun, and at frequent intervals masses of light 

 vapour blew up from the valley and enveloped the summit in 

 their mist. Suddenly, at 6.30 a.m., the sun peeped through a 

 cbink in the eastern sky, and we saw a shadow of the Peak pro- 

 jected on the land ; then a little mist drove in front of the 



