NA TURE 



THURSDAY, MARCH 26, igoS. 



.1//SL£.4D/A'G SEISMOl.OG Y. 

 Earthqiinkcs, an hitrodiiction to Seismic Geology. 

 By William Herbert Hobbs. Pp. xxxi + 336. (New 

 York : D. Appleton and Co., 1907.) Price 2 dollars 

 net. 



EARTHQUAKES have come home to us of late, 

 and \ve presume that the more general interest, 

 which is now taken in them, is the cause of the pub- 

 lication of this book, on a subject with which the 

 author seems very imperfectly acquainted. The key- 

 note "f the work i: struck very early in the book, in a 

 sumn.arv of the history of modern seismology, which 

 would lead one to suppose that little of any import- 

 ance had been done outside Germany and Austria ; no 

 mention is made of the Seismological Society of 

 Japan, and it is erroneously stated that the Inter- 

 national Seismological Association has " published at 

 regular intervals the ' Beitrage zur Geophysik.'" 

 The reports of the sessions of the association have 

 certainlv been published as supplementary volumes of 

 this periodical, which is an independent publication, 

 and one of the reasons for the abstention of those seis- 

 mologists who have held aloof is that the association 

 has been made to appear as the appanage of a private 

 venture. 



A large part of the book is devoted to the geological 

 aspect of seismology, and in this we find what the 

 author regards as his contribution to the science. He 

 plots on a map the places at which earthquakes have 

 been felt, or have exhibited a greater degree of 

 violence, draws a series of straight lines through 

 them, which he calls seismotectonic lines, and regards 

 it as a remarkable fact that these lines should inter- 

 sect at the points through which they are drawn. To 

 a small extent the " seismotectonic " lines represent 

 a truth which has long been known to students of 

 seismologv, but by far the greater number of them 

 are mere figments of the pencil and the ruler, and it 

 is remarkable that the author should make no refer- 

 ence, in this connection, to Col. Harboe's theory of 

 extended earthquake origins, a theory which has 

 some resemblance to that of Prof. Hobbs, but is 

 based on more extensive data, and makes no attempt 

 to force the origins into straight lines. 



The author's unfamiliarity with the subject is most 

 conspicuous in his treatment of seismometry, whether 

 by observation of the effects of earthquakes or by 

 the use of instruments. We find no mention of West's 

 formula, or even of acceleration as the cause of 

 earthquake damage, but we do find a most remark- 

 able suggestion that the " simplest and one of the 

 best " of seismoscopes may be made by setting up an 

 ordinary lead pencil upon its end, in part immersed 

 in a bath of sand ; it is gravely added that an inch 

 scale may be marked on the pencil by simple notches, 

 to enable the depth of the immersion to be recorded. 

 We can imagine the enthusiastic seismologist frantic- 

 ally digging out the ruins of his dwelling and 

 anxiously determining the direction in which the 

 NO. 2004. VOL. 77] 



pencil, embedded, say, only three inches in the sand, 

 had been overturned! Seriously, we wonder if Prof. 

 Hobbs has any idea of the shock necessary 

 to overturn a lead pencil standing on a smooth, 

 hard surface, let alone embedded in sand; it seems a 

 very unstable object, and easily upset, but the shock 

 which will throw it down is severe enough to alarm 

 many people, and even to cause damage to buildings ; 

 moreover, the direction of overthrow is now known 

 to indicate little or nothing regarding the wave 

 motion of the earthquake. After this it is not sur- 

 prising that the description of the horizontal pendu- 

 lum seismograph should be wrong both as to theory 

 and practice. 



This brief review of some of the more striking 

 faults in the book must not be supposed to mean 

 that it is altogether bad. As an introduction to 

 seismology, or even to seismic geology, it is the most 

 misleading that we know, but for the reader who 

 comes to it with sufficient previous knowledge it con- 

 tains suggestive passages, and as we perused the book 

 we were haunted by the consciousness that its author 

 was capable of better work ; we searched for the word 

 which would describe its character until a marginal 

 heading, in block type, supplied the want in " crude- 



GERMAN SCHOOL BOTANY. 

 (i) Mikroskopisches und physiologisches Praktikum der 

 Botanik fur Lehrer. By G. MuUer. Pp. xvi + 224. 

 (Leipzig and Berlin : B. G. Teubner, 1907.) 

 Price 4.80 marks. 



(2) Handboek der botanische Micrographie. By Dr. 

 J. W. Moll. Pp. .\xii + 3SO. (Groningen : J. B. 

 Wolters, 1907.) Price 4.25 francs. 



(3) Grundziige der Pflanzenkitnde. By Prof. K. 

 Smalian. Zweite Auflage. Pp. 288; with 36 coloured 

 plates. (Leipzig : G. Freytag; Vienna : F. Tempsky, 

 1908.) Price 4 marks. 



(4) Anatomischc Physiologie der Pflanzen und der 

 Menschen. By Prof. K. Smalian. Pp. 86. (Leipzig : 

 G. Freytag; Vienna: F. Tempsky, 1908.) Price 

 1.40 marks. 



(1) A LTHOUGH it is the general practice among 

 i\ teaching botanists to combine in lectures the 

 explanation of physiological principles with descriptions 

 of the organs involved, the combination of microscop- 

 ical anatomy with physiology in a practical book is 

 unusual. In the present instance there is complete 

 separation into a course of microscopical exercises that 

 occupies about three-quarters of the volume, and a set 

 of physiological experiments and deductions. The ana- 

 tomical course begins with a description of the neces- 

 sary apparatus for microscopical technique, after which 

 there follows a series of studies of the cell, stem, leaf, 

 and root, nearly identical with the types in Stras- 

 burger's " Botanisches Praktikum," in so far as these 

 relate to flowering plants. This part of the book is 

 excellent, especially for teachers who wish to become 

 thoroughlv conversant with all details and skilled 

 in manipulation. The directions are explicit, the hints 

 on reagents and methods are practical, and the accom- 



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