268 



NA TURE 



[January 20, 1898 



mercuric salts give a precipitate with sulphuretted 

 hydrogen which changes from white to black, and is 

 insoluble in alkaline sulphides ; that hydrochloric acid 

 and chlorides give no precipitate, and that iodide of 

 potassium gives a beautiful red precipitate very soluble 

 in excess of the reagent. These are all the qualitative 

 reactions given for mercuric salts, and it may well be said 

 of them that, though true, they are not the whole truth 

 even concerning the precipitates mentioned. As a reminder 

 for students who have to learn what they can about many 

 things in a very little time, the volume will no doubt 

 prove very valuable, and the practical analyst will some- 

 times find suggestions that will prove useful to him. 



First Book of Physical Geography. Bv Ralph S. Tarr, 

 B.S., F.G.S.A. Pp. xxviii + 368. (New York: The 

 Macmillan Company. London : Macmillan and Co., 

 Ltd., 1897-) 



Prof. Tarr explains that his reasons for following 

 his "Elementary Physical Geography" (noticed in 

 Nature, vol. liii. p. 293) by the present smaller work, 

 is that "many teachers who wish to give instruction in 

 the new physical geography are unable to make use of 

 it," on account, apparently, of the educational regulations 

 in the United States. Although Prof Tarr italicises the 

 new physical geography., we are unable to see that this 

 book differs essentially in subject-matter from such a 

 long established schoolbook as Geikie's " Elementary 

 Lessons in Physical Geography"; and although with 

 regard to arrangement and style there are variations, 

 these present no special novelty. 



Part i. deals with the earth as a whole, and some facts 

 of astronomy; Part ii. — entitled "The Atmosphere" — 

 also touches on light, heat, electricity, magnetism, and 

 the distribution of animals ; Part iii. treats of the ocean ; 

 and Part iv. of the land. The last part is by far the best 

 from every point of view, and the treatment of the action 

 of rivers on the land is quite beyond anything we have 

 seen in other books of similar scope. This department 

 of physical geography has received more attention in 

 America than in Europe, and we are grateful to Prof. 

 Tarr for the way he has handled it. It is unfortunate 

 that the other parts do not rise to the same level. The 

 illustrations, however, are all very good. 



No doubt some terms are used in a different sense 

 in this country and in America, e.g. physiography, which 

 here is wider than physical geography, is there restricted 

 to geomorphology. It appears that zone is held to signify 

 simply a division, e.g. "there are three great zones of 

 life . . . tlie ocean, the land, and the fresh water " (p. 

 165) ; and "in lieu of" (p. 27) is used where we would 

 say "in view of" The term adulteration, on p. 33 

 ("nitrogen . . . acts as an adulterant to the active oxygen 

 in a manner similar to the adulteration or weakening of 

 a solution of salt when water is added to it "), is used 

 evidently in the sense of dilution, and is not intended 

 to convey any suggestion of fraudulent mixture. But, 

 making allowance for differences of custom in the use of 

 words, we have noted several cases of very slack or even 

 careless definition. There is also a want of attention to 

 the minutiie of terminology which must be very puzzling 

 to the teachers who use this book, if their mode of 

 doing so is the same as that adopted by their brethren 

 in this country. In a new edition these blemishes 

 will doubtless disappear, and we point them out merely 

 with that object. Such vague sentences as the following, 

 on wind as the cause of waves, should also be revised : 

 " If the wind continues, and especially if it freshens, the 

 waves become higher, for the cause is increased because 

 then there is more friction '' (p. 206). 



The occasional descriptions of instruments, e.g. the 

 psychrometer, anemometer, and especially the deep-sea 

 sounding-rod, are inadequate and sometimes misleading. 



NO. 1473. VOL. 57] 



On the current chart (p. 214) the important and very 

 distinct Agulhas current is not named ; and in the 

 sketch-map of the distribution of volcanoes, on p. 355, 

 the active volcanoes which have been definitely proved 

 to exist in Central Asia and Central Africa are not 

 shown. H. R. M. 



Arii e llalici. By G. Sergi. Pp. iv -|- 228. (Torino : 

 Fratelli Bocca, 1898.) 



Prof. Sergi may be congratulated on the lucid manner 

 in which he describes the earliest inhalsitants of Italy, 

 and the effects produced by the various invasions of that 

 country. From conclusions drawn from anthropological 

 observations he leads us to believe that the Aryans firbt 

 invaded Italy from the north-west, and established them- 

 selves on the banks of the river Po, terramara being 

 found in that locality. These mixed with the Mediter- 

 ranean race, and spread south-east, leaving the country 

 around Genoa undisturbed ; towards the end of the eighth 

 century before the Christian era, the Etruscans landed 

 on the banks of the Tiber and mixed with the in- 

 habitants of Umbria. No satisfactory explanation of the 

 foundation of Rome is offered. 



Anthropological detail is restricted to skulls found in 

 tombs ; the method of description is that first introduced 

 by the author, which is based upon the appearance of 

 the skull viewed in ?iorina verlicalis. 



The construction of terramara and lake dwellings, the 

 various kinds of pottery and vases, are briefly described 

 in. the chapters dealing with archaeology. 



The origin of the Italian language and the anthro- 

 pological evidence in favour of the suggestions of 

 Schleicher, Lottner, &c., is carefully weighed. 



It would assist the study of ethnology if the inhab- 

 itants of the other European countries were dealt with in 

 as brief and scientific a manner as those of Italy have 

 been by Sergi in " Arii e Italici." 



Laboratory Practice for Beginners in Botany. By 

 William A. Setchell, Ph.D., Professor of Botany in the 

 University of California. Pp. xiv -|- 199. (New York: 

 The Macmillan Co. London : Macmillan and Co., Ltd., 

 1897.) 



This little book is, on the whole, admirably calculated to 

 fulfil the intentions of its author. The young student is 

 directed to observe simple and readily accessible objects, 

 and his reasoning faculties are at the same time stimu- 

 lated by an indication of the general principles which the 

 selected examples are intended to illustrate. By the 

 time he has worked through the book, a boy will have 

 acquired a fair knowledge of the gross structure 0/ 

 plants — a knowledge quite as important as that of minute 

 structure which he too often has never seen for himself, 

 or of physiology which, when ignorant of chemistry and 

 physics, he cannot understand. 



Some of the suggestions to the teacher are excellent, but 

 we can hardly praise the selection of literature suggested 

 for his use. A teacher ought to know where to seek for 

 the facts he may have temporarily mislaid ; and if he 

 really requires the aid Prof Setchell is ready to render 

 him in this respect, he is clearly unfit to teach. 



" On a Sunshine Holyday." By the Amateur Angler. Pp 

 viii -f- 140. (London : Sampson Low, Marston, and 

 Co., 1897.) 



The short — very short — papers collected in this booklet 

 originally appeared in the Fishing Gazette. The author 

 confesses that he is " well aware that from the standpoint 

 of literature these papers possess no claim for a separate 

 existence." He might also have added that, from a 

 scientific point of view, there is even less justification for 

 their publication. 



