172 



NA TURE 



[J UN 



E 2 1, 1900 



the Weierstrassian function-theory upon other branches 

 of analysis, and in particular upon the problems of celestial 

 mechanics, is truly remarkable. 



It is to be hoped that the publication of Prof. 

 Forsyth's work will make English mathematicians 

 better acquainted with current research on the subjects 

 with which he deals. The value of his treatise for really 

 competent readers is evident, and needs no commenda- 

 tion. But we may, perhaps, regret that he has not more 

 definitely considered the interests of the rising genera- 

 tion. It is most important that new ideas and recent 

 methods should be introduced to young men of ability 

 while their minds are keen and susceptible ; and their 

 interest is seldom aroused in the first instance by a treatise 

 which aims at being exhaustive. To take an example 

 in point ; few readers, we imagine, to whom the subject 

 was new, would persevere in the study of Lie's great 

 work on transformation-groups ; yet what mathematical 

 student could fail to be delighted with his lectures on 

 differential equations with known infinitesimal trans- 

 formations, as edited by Dr. Scheffers ? 



No doubt the task of writing an introductory, and 

 thoroughly didactic, treatise on the modern aspects of 

 this theory is very difficult ; more so, very likely, than 

 the one to which Prof. Forsyth has applied himself. 

 The selection, combination and assimilation required 

 would demand a great deal of care and judgment; a 

 certain lightness of touch would also be desirable, and 

 this is not easy to maintain after a course of reading in 

 the extremely ponderous memoirs which are so often 

 found in the literature of the subject. But a work of 

 this kind might do more than the most conscientious 

 handbook to encourage a living interest in the theory of 

 differential equations. There is some appearance of a 

 tendency to over-elaboration in English treatises pre- 

 sumably written for students ; to authors as well as to 

 lecturers may be commended the maxim " Above all, do 

 not be dull." G. B. M. 



OUR BOOK SHELF. 

 Origin and Character of the British People. By Nottidge 



Charles Macnaniara. Pp. 242 ; 33 figures. (London : 



Smith, Elder and Co., 1900.) 

 Mr. Macnamara seeks, in a small compass, to indicate 

 the origin of the component parts of the British people, 

 and to account for the differences of local moral 

 character by proportionate inheritance from the original 

 races, all of which are assumed to have their mental 

 and moral peculiarities as fixed as their physical cha- 

 racters. He believes that the Iberians, as he prefers to 

 call the Mediterranean or Afro-European race, formed 

 the primary stock from which the existing inhabitants of 

 Great Britain and the West of Europe are derived ; and 

 that they are the modified descendants of Palaeolithic 

 man. The tall fair Aryans originated in Western Asia. 



The pioneer migration of the Aryans into Europe 

 formed the Cro-Magnon race ; then came the dolmen- 

 builders, the South Mediterranean branch extending 

 from the Amorites to the "fair Libyans" ; the migrants 

 into Central Europe mixed with the brachycephals and 

 constituted the " Celts." A distinct northern migration 

 formed the Teutonic Aryans. 



The author also believes that dolmens and long barrows 

 are everywhere the work of the Aryan race. The pre- 



NO. 1599, VOL. 62] 



historic tall brachycephals of Northern Europe were a 

 branch of the Northern Mongolian or Turanian race. 

 The short dark brachycephals of Central Europe brought 

 the art of working in bronze from Asia, presumably from 

 Burmah. The Formorians of Ireland were Iberians ; in 

 North-west Ireland are still to be found descendants of 

 the Northern Mongoloid race ; the Firbolgs were Celtic 

 Aryans or dolmen-builders. The Southern Mongoloids 

 arrived in the bronze age ; these are the Tuatha de 

 Danann. A second invasion of Aryan Celts, or Mile- 

 sians, arrived in Ireland also during the bronze age. This 

 abstract gives a fair idea of the scope and views of the 

 author. 



The Geography of the Region about DeviPs Lake and the 

 Dalles of the. Wisconsin. By Prof. R. D. Salisbury 

 and Mr. W. W. Atwood. Pp. x+151. (Madison, 

 Wisconsin : Geological and Natural History Survey, 

 1900.) 



This is the first number of an "Educational Series" to 

 be published by the Wisconsin Geological and Natural 

 History Survey. The region to which attention is now 

 particularly called is in the south-central part of 

 Wisconsin, and it is of interest because it well illus- 

 trates many points in the geographical evolution of land- 

 surfaces. It comprises an undulating plain chiefly of 

 Potsdam Sandstone, with some areas of magnesian 

 limestone, and with a northern and southern range of 

 bold quartzite hills. The southern range rises from 300 

 to 800 feet above the surrounding land, or up to 1600 

 feet above sea-level, and in the bottom of a deep gap, 

 which divides this range, lies Devil's Lake. This is a 

 lake which, in glacial times, occupied an enclosure be- 

 tween the ice on the one hand and the quartzite 

 ridge on the other : a gorge which originally was 

 the work of a pre-Cambrian stream. The melting 

 of the ice supplied abundant water, and the lake rose 

 perhaps 90 feet above its present level. In this and in 

 many other cases the irregular deposition of glacial drift 

 gave rise to many depressions without outlets, in which 

 surface-waters collected after the ice had disappeared. 

 Few of these lakes now remain in the region, but Devil's 

 Lake, which is more than a mile in length and half a mile 

 wide, occupies an unfilled portion of an old river valley, 

 isolated by great morainic dams from its surface-con- 

 tinuations on either hand. Streams originate beyond these 

 dams. The " Dalles " are sandstone cliffs which form a 

 gorge along the Wisconsin River for a length of about 

 seven miles, and a depth of 50 to 100 feet. The effects of 

 weathering by atmospheric agents, and of erosion by the 

 river, are well exhibited, and the views remind us of the 

 rock-scenery along the Eden near Corby Castle. 



The volume, which, with its index, extends to 1 5 1 pageis, 

 is in reality an essay on the origin of scenery treated from 

 a geological point of view. The authors deal with the 

 pre-Cambrian history of the quartzite, from its origin in 

 loose sand to its uplift and deformation ; and they deal 

 similarly with the other strata. They contribute also a 

 fairly full account of the phenomena of the Glacial period, 

 and of the work of rain and rivers. Numerous excellent 

 photographic representations of the scenery are given, 

 including views of various natural arches, tors, anct 

 needles. 



Monistische Gottes- und Weltanschauung. Von J. Sack. 



Pp. viii -f- 278. (Leipzig : Engelmann, 1899.) 

 In Herr Sack's view all particular existences are modes 

 of one spirit-substance — God. He calls this doctrine 

 monism, and not pantheism, because he thinks the latter 

 not incompatible with polytheism. Be this as it may, 

 the distinguishing mark of his thesis is that it works to 

 an Hegelian doctrine of being along the lines of a 

 naturalistic theory of becoming that might satisfy Mr. 



