December, 1901.] 



KNOWLEDGE. 



265 



^i£N€E J.iTER ATURE kJ^/ 



Founded by RICHARD A- PROCTOR. 

 Vol. XXIV.] LONDON: DECEMBER, 1901. [No. 194. 



CONTENTS. 



m PA8F 



Editorial 2C5 



The White Nile — From Khartoum to K.iwa.- VI. 



A Dance, a Sand-Storm, and a Rare B rd. liy 



Uarhy F. WiinEKBY, r.z.3., m.b.o.c. (Illustrated) ... 266 

 A Remarkable Mammal. By R. Lyiii:kkeh . 2(!l 



Head and Fore quarters of the Aye Aye. {Plate.) 

 The Real Paths of Fireballs and Shooting Stars. Bv 



W. F. l>KNMNa, F.B..\.S. (Illustrate,!) .". 271 



Constellation Studies.— XI. The Ram and the Bull. By 



F. Waltkb M.\r>"DER, F.ii.i.s. (Illustrateil) ... ... 273 



Letters : 



Buii.Li.iNT Metbob in Californh. By S. D. Beoctok 276 



Does the Moon .Affect EAixFALLy Bv Alex. B. 



MacDowall. (Illustrated J " 276 



Notes 277 



Notices of Books 278 



Books Received ... ... ... ... ... ... 280 



British Ornithological Notes. Conducted by Uaebt F. 



WiTHERBT. F.Z.S., M.B.O.T 28] 



Flowering Plants, as Illustrated by British Wild- 

 Flowers. — VI. The Vegetation of Ireland. By 

 E. LlOTD Pbabges, B.A. (Illui-tratedJ .. 281 



Microscopy. Conducted by il. I. Ceoss. {Illustrated) ... 285 



Notes on Comets and Meteors. By W. F. Denning, 



F.B.A.s. ... ... ... ... ... ... ... ... 286 



The Face of the Sky for December. By A. Fowlee, 



F.E.A.S. ... ... ... ... ... ... ... ... 287 



Chess Column. Bv C. D. Lococe, b.a 287 



EDITORIAL, 



Before proceeding to outline brieily our programme for 

 the new year, the pleasing duty again devolves upon us 

 of acknowledging our indebtedness to our Contributors 

 for the very thorough manner in which they have 

 enabled us to fulfil our promises, and to add still another 

 volume of Knowledge to the series. To this expression 

 of our thanks, we add an appreciation of the steady and 

 increasing support which our Subscribers have given to 

 cur efforts to make Knowledge a trustworthy and 

 popular medium of scientific thought. 



In a day when the spread of science and literature has 

 given the public a well-nigh limitless supply of new and 

 remarkable facts, it is regi-ettable that the true meaning 

 of these facts is too often hidden from the public view 

 by the reserve of specialists. It is our earnest hope, 

 therefore, that an increasing nun:;ber of those who have 

 it in their power to stimulate and satisfy the desire for 

 a clear and definite perception of the worth and large 

 issues of scientific discovery may be induced to do so. 



The increasing public interest in the study of 

 Astronomy, to which we referred last year, has been 

 evidenced in the interest aroused by Mr. Maunders 

 comprehensive "Constellation Studies"; the concluding 

 paper in this series will appear in the January 

 issue, when the whole twelve studies, together with the 

 previous series on " Astronomy without a Telescope," 



will bo carefully revised by the Author prior to their 

 issue as a volume in tho Knowledge Librai*y. Mr. 

 M.uuider is also engaged on a new series of papers 

 dealing with some of the results of Spectrum Analysis. 



Among the other Astronomical projects for which 

 arrangenionts have been now coiuplctod, wo may mention 

 a descriptive account of the Starfield Observatory from 

 tho pen of Dr. Isaac Roberts, to whose work Astronomers 

 are so much indebted ; a paper on the Spectrum of Nova 

 Persei, by the Rev. W. Sidgicaves, s.j. ; and two articles 

 from Mr. A. C. D. Cronimelin, who proposes to deal with 

 Eclipse Cycles, and with the actual path of the Moon in 

 space. Fiu-ther interesting contribuf>ions are promised 

 by some writers new to our pages, and among these wo 

 may mention tho Rev. T. E. Phillips on '' The CuiTents 

 of Jupiter's Atmosphere " ; Professor R. A. Sampson on 

 ■ Tho Almucantar of Durham Observatory," and on 

 "The Mechanical Constitution of the Sun"; and Mr. 

 Alexander Smith on '' The Methods, Difficulties, and 

 Results of Stellar Photography." 



Mr. W. F. Denning will continue to contribute 

 " Notes on Comets and Meteors ' ; while " The Face of 

 the Sky ' will appear month by month as heretofore, bub 

 will be edited during tho coming year by Mr. W. 

 Shackleton. 



We are happy to welcome back to the pages of 

 Knowledge an old friend in tho person of Mr. E. A. 

 Butler, who will commence in tho January number a 

 series of illustrated entomological articles. In Botany, 

 Mr. R. Lloyd Pracgcr will contribute a new series of 

 papers, of which the first will deal with " Plant 

 Colonists " ; and the Rev. Alex. S. Wilson will write on 

 " Vegetable Mimiciy." Much interest has been aroused 

 during the past year by the Rev. J. M. Bacon's balloon 

 expeditions, and Mr. Bacon has promised to write for 

 us on " Tho Air above London," and on " The Clouds 

 as seen from Cloud Level." 



Tho Rev. T. R. R. Stebbing informs ns that the fulfil- 

 ment of his promise to write on some singular groups of 

 Arthropotla may bo regarded as still in view, the proniiso 

 not forgotten, though tho fulfilment has been deferred. 

 Prof. Grenville A. J. Cole will return t.o our columns 

 with an article on tho groat granite chain of south-east 

 Ireland, " The Backbone of Leinster"; and he will also 

 write on " Tho Plain of Prussia." Mr. Hariy F. 

 Witherby will record his experiences on an ornithological 

 expedition to Russian Lapland. Contributions have also 

 been promised by Mons. E. M. Antoniadi, Mr. R. 

 Lydekker, Dr. Hugh Robert Mill, and other writers. 



Mr. M. I. Cross will continue to conduct the 

 Microscopy cohunn. This subject could bo made 

 increasingly helpful and interesting by the co-operation 

 of rcAders and workers, and not«s and suggestions are 

 invited. It is propo.sed at intervals to offer to readers 

 of Knowledge material for mounting as microscopical 

 slides, with instructions for tho processes, and descrip- 

 tions of the objects. It is hoped that readers will them- 

 selves contribute material for distribution with descrip- 

 tions, and so add to the usefulness of tho suggested scheme. 



In the Chess Column, the Solution Toumey which 

 Mr. Locock has conducted during the closing year ha-s 

 proved an unqualified success, and has induced Mr. 

 Locock to project for the new year a three-move 

 Problenr Tourney and also a Solution Toumey to run 

 concurrently with it. Tho particulars of both these 

 contests will bo found in the Chess Column. 



It will be gathered from tho foregoing that a large 

 part of our volume 'for the coming year is provided for, 

 but wo are always glad to receive contributions con- 

 sidered suitable for oui- pages. 



