October 24, 1907] 



NA TURE 



635 



WILT) LIFE AND ADVENTURE. 



Mild Life in Australia. By W. H. D. le Souef. 

 Pp. XV + 439; illustrated. (Christchurch : Whit- 

 combe and Tombs, Ltd.) Price 7^. 6d. net. 



The Life-Story of a Squirrel. By T. C. Bridges. 

 Pp. vii+230; illustrated. (London: A. and C. 

 Black, 1907.) Price 6s. 

 Adventures in the Great Forests. By H. W. G. 

 Hyrst. Pp. 330 ; illustrated. (London : Seeley 

 and Co., Ltd., 1908.) Price 5s. 



Heroes of Pioneering. By E. Sanderson. Pp. 352 ; 

 illustrated. (London : Seeley and Co., Ltd., 1908.) 

 Price 5s. 



IN re-publishing, with considerable additions, the 

 series of natural history articles which originally 

 appeared in the ]'ictorian Naturalist and the Eniti, 

 the author of " Wild Life in Australia " has assuredly 

 been well advised ; for within this unassuming little 

 volume is to be found a valuable store of information 

 concerning the animals and plants of various districts 

 in Australia. The province of Victoria, the Riverina 

 district of New South Wales, the islands of Bass 

 Strait, Queensland, and Western Australia are in turn 

 discussed ; and in each case the treatment of the sub- 

 ject is full of interest, although the amount of space 

 devoted to each district is by no means large. The 

 most important observations in the book are those 

 relating to the life-historv of the duckbill or platypus. 

 Many of our readers will recall that in 190 1 Mr. G. 

 Metcalfe, at a meeting of the Zoological Society, 

 denied that the platypus lays eggs. Mr. le Souef, on 

 the other hand, definitely states that at the end of 

 October the creature lays one or two eggs, which are 

 of elongated form and furnished with a leathery shell. 

 The egg is believed to be soon hatched, and the newly- 

 hatched young is naked, and about one inch in length. 

 A nest and broken eggshell were, according to 

 the author, forwarded to Dr. P. L. Sclater. The 

 point in dispute may now be regarded as settled. Mr. 

 le Souef adds that the platypus is a good climber, and 

 that when on land it folds inwards the portion of the 

 web projecting beyond the toes, so that the latter may 

 be enabled to obtain a grip of the surface. 



So far as the naturalist is concerned, " The Life- 

 Story of a Squirrel " is effectually condemned bv the 

 illustrations, which (although of passable excellence 

 from the conventional standard) represent the squirrel 

 as being wholly red above, with long ear-tufts, at all 

 seasons. In the winter scene facing p. 142 the char- 

 acteristic grey flanks are not shown ; while in the 

 plate facing p. 32, which is stated in the text to repre- 

 sent a larch, and must therefore, as the tree is in 

 leaf, indicate summer, the squirrel is likewise shown 

 with ear-tufts and the chestnut tail of winter. The 

 text is not of a nature that commends itself to our 

 taste, or, it may be added, to that of certain young 

 people to whom we have shown the volume. For our 

 own part, we like either a sound book on natural his- 

 tory or a good novel ; the attempt to combine the two 

 does not appeal to us. 



Of the two remaining volumes mentioned above, a 

 brief notice must suffice, seeing that both are based 

 NO. 1982, VOL. 76] 



on more or less well-known stories of travel and adven- 

 ture or on striking historical events, and appear to be 

 mainly intended for boys. In both instances the 

 authors are to be congratulated on their selections 

 and on the interesting style in which these are placed 

 before the public. In his preface Mr. Hyrst records 

 a protest against the destruction of forests which is 

 proceeding only too rapidly in many parts of the world, 

 quoting a statement to the effect that seven acres of 

 primeval forest are felled to meet the requirements of 

 the paper-maker for a single day's issue of a New 

 York journal. Adventures in the great forests of the 

 world, rangine from Major Stedman's expedition in 

 Surinam in 1772 to the journeys of Speke and Grant, 

 Winwood Reade, and other comparatively modern 

 African explorers, are recorded in a style which should 

 attract all juvenile readers. Mr. Sanderson carries his 

 readers further backwards in time, commencing with 

 Sir Walter Raleigh in Virginia, and continuing his 

 narrative down to the establishment of British 

 supremacy in Rhodesia and Nigeria. 



OUR BOOK SHELF. 



The Collected Mathematical Works of George William 

 Hill. Vol. .iv. Pp. vi-l-460. (Washington : The 

 Carnegie Institution, 1907.) 



The fourth volume of Hill's mathematical works brings 

 the re-publication of these papers up to date, and a 

 little beyond it; for it includes four memoirs that have 

 not appeared elsewhere, and are of very considerable 

 interest. It is, indeed, difficult to overstate the interest 

 of the whole volume — at least, to those occupied in the 

 subjects treated of. Newcomb, in his " Reminis- 

 cences," permitted himself a good-natured grumble at 

 Hill's "lack of the teaching faculty." It seems to 

 us that for true instruction as to what the problems 

 of celestial dynamics actually require, and what are 

 the most hopeful ways of approaching them, nothing 

 has appeared since Laplace's " Mecanique Celeste " 

 that so well deserved study as these four volumes. 

 One cannot do them justice in a brief notice. Gener- 

 ally we should say their unique force is a force of 

 character, a serious purpose to adhere only to real 

 problems, to which great analytical facility, with 

 clearness and fastidious elegance, and immeasurable 

 patience are subservient. 



Passing over the minor papers, and one of much 

 interest not hitherto published — No. 84, " On Dvnamic 

 Geodesy " — the chief part of the volume is engaged 

 in the attempt to find integrals of the planetary 

 equations of motion which shall be valid for an in- 

 definite lapse of time, and so supply some conclusive 

 information as to the permanent future stability, and 

 equally as to the past history of our system. This 

 may be said to be the problem of vital interest at the 

 present time in this branch of astronomy. Construc- 

 tion of tables of the actual motions of the planets is 

 so far perfected that their remaining interest is almost 

 wholly technical. On the other side, if we mav take 

 the opinions expressed by Hill in No. 60, " Remarks 

 on the Progress of Celestial Mechanics since the 

 Middle of the Century," the efforts of even very bril- 

 liant analysts have not succeeded in throwing much 

 light upon the problem of representing the motions by 

 more general integrals. 



Without claiming too much for what Hill himself 

 here contributes, his memoirs are instructive as giv- 

 ing almost a history of the efforts, extending over 



