JuLv 1 8, 1895] 



NA TURE 



267 



AN ECLECTIC HISTORY OF SCIENCE. 

 Progress of Sciemc. liy J. X'illin Marmery. Pp. 357. 

 (London : Chapman and Hall, Limited, 1895.) 



THE custom of inserting laudatory prefaces or in- 

 troductions, written by well-known men, in works 

 of science by lesser lights, which was commented upon 

 in these columns a few weeks ago, reaches the ridiculous 

 in the case of this book. A letter from Mr. Samuel 

 Laing to the publishers is printed, in the course of which 

 he says : " I have now had time to read .Mr. Marmery's 

 book, and find it a work of great learning and research 

 . . . and I can confidently recommend it as alike in- 

 teresting and instructive." What induced the publishers 

 to print this purely business letter as a testimonial to 

 the book's good qualities, passes our comprehension. A 

 book usually finds its proper level, and the effort to 

 force it into a higher position by means of a letter of 

 introduction from a more or less distinguished individual, 

 must pro\e futile ; for in literature, scientific or other- 

 wise, authors are judged entirely by their own works. 



Ever)' one will recognise that to attempt to condense 

 the history of science into a volume of about three hundred 

 and fifty pages, is to court failure. .-Ml that can be ac- 

 complished in so small a space is to describe the well- 

 defined steps of advancement along the road of natural 

 knowledge, and to exhibit the continuity of scientific 

 developments. Mr. Marmery has done this with a fair 

 amount of success. After briefly noting the knowledge 

 of the Egyptians and Chaldeans so far back as 3000 B.C., 

 he surveys the successive stages in the history of science, 

 and devotes a few lines to men and matters of first- 

 rate importance in each. His statement of the progress 

 made by the .Arabians from the ninth to the fifteenth 

 centuries, brings into view the substantial achievements 

 of a people which then stood in advance of the wi-.ole 

 world. Our obligations to the Arabs are indubitable ; 

 nevertheless, i^w European historians ha\e expressed 

 them. " Eminence m science is the highest of honours" 

 was a maxim which represented the bearing of Islam 

 towards scientific knowledge at a period when Europe 

 was ruled by monkish philosophy, and when investigators 

 were stamped as heretics. 



The review of the science of the Greek, the Arabian, 

 the Mcdiiuval, and the Revival periods, leads to the 

 science of the Modern period, from the end of the 

 sixteenth century to the present time. And here the 

 author treads upon dangerous ground. He has had, 

 perforce, to create invidious distinctions by selecting from 

 the host of scientific workers those that appear to him 

 to have added most to the store of knowledge. Huxley 

 got over the difficulty in his address on " The Progress 

 of Science," published among his collected essays (vol. i.), 

 by omitting references to all living men, and by dealing 

 only with results. Mr. .Marmery might ha\e saved him- 

 self from hostile criticism by following the same method ; 

 but, in that case, his volume would have wanted the 

 \ery information which is the chief justification for its 

 existence. H is selection of names has, he says, been deter- 

 mined " by what appears typical origiiui/itv in the work, 

 rather than by what is imposing in extent and weight." 

 Hero and there we fancy this criterion has not been 

 applied : but in a book covering so wide a scope, such 

 NO. 1342. VOL. 52] 



deficiencies may well be excused. Modern investigators 

 are divided into seven groups, viz. (i) biologists, (2) 

 geologists, (3) chemists, (4) mathematicians, (5) astro- 

 nomers, (6j physicists, (7) eminent practical men. Short 

 accounts of the main achievements of the individual 

 workers in each group are given, and are fairly trust- 

 worthy. In an appendix, the names of foremost men of 

 science in all the periods are tabulated, and a copious 

 index makes it easy to find the sketch of the works of 

 any one of them. 



Many imperfections the book certainly has, but in spite of 

 them we think it deserves some words of commendation. 

 Those who wish to know something about the evolution of 

 scientific knowledge, and the multitude of readers who 

 like to dip into a book to find what this or that man 

 of science has done, may obtain from this handy volume 

 the information they seek. We could easily enumerate a 

 score of names which ought to find a place in the book, 

 but are wanting. Probably it was because the author 

 was aware of the incompleteness of his record, that he 

 omitted the definite article from the title of his book. 



MICROSCOPIC STUDY OF ROCKS. 

 Petrology for Students : an Introduction to the Study of 

 Rocks under the Microscope. By .A.. Harker. (Cam- 

 bridge L"niversity Press, 1895.) 

 THIS latest addition to the Cambridge Science 

 Manuals is intended by the author as a guide to 

 the study of rocks in thin slices under the microscope 

 In scarcely another English text-book on the subject has 

 the treatment of rocks from the purely petrographical 

 point of view of microscopic examination been so strictly 

 adhered to throughout as in the book before us. 

 " Microscope " is almost the first word in the book, and 

 sounds the key-note of the whole. 



.\fter a short introduction, containing a few notes on 

 the optical properties of minerals, the author plunges at 

 once into the systematic description of the different rock 

 species. The usual chapters on the characters and 

 methods of separation and determination of the rock- 

 forming minerals are omitted altogether ; for all such 

 niineralogical points, the reader is referred to standard 

 works on the subject. The book, therefore, corresponds, 

 though on a much smaller scale, to the second volume of 

 such text-books as those of Rosenbusch and Zirkel. 



In the classification of the massive igneous rocks the 

 author divides them into plutonic, intrusive and volcanic, 

 but is careful to point out that the divisions themselves 

 are based upon the structural characters resulting from 

 the different conditions of consolidation. This classi- 

 fication resembles that of Rosenbusch, but the author's 

 intrusive groups do not correspond exactly with the 

 Ganggesteine of Rosenbusch, for he extends them to the 

 basic family, whereas even Rosenbusch considered this 

 to be impracticable. In this connection we notice that 

 those much abused terms "diabase" and " porphyrite "' 

 receive new definitions. Diabase is in this book used to 

 designate, not pre-Tertiary or altered dolerites, but the 

 group of intrusive basic rocks corresponding to the 

 volcanic basalts, while porphyrite is applied to the 

 intrusive rocks corresponding to the volcanic andesites. 

 The author, of course, follows the British school in admit- 



