November 4, 1509] 



NATURE 



same way that the other regulates our recognition 

 of Becoming. 



• Examining the character and contents of human 

 experience by the aid of this theory of faith, the 

 author finds that it yields no support to the belief in 

 a continued personal existence. On the contrary, he 

 detects in the moral consciousness a recognition that 

 the permanent element in us is an Entelechy that 

 produces our " personality " as a purely temporary 

 phenomenon, and will in due time pass upon its way. 

 It draws from an underlying sea of infinite, un- 

 imaginable Being, and our individualities are, as it 

 were, merely the waves in which, from moment to 

 moment, the ceaseless movement of this sea expresses 

 itself. 



It is unlikely that the reader will be able to agree 

 with all Count Keyserling's views; in particular, 

 he will probably feel that the concept of faith as a 

 purelv formal fmjction is by no means clear. His 

 dissatisfaction with this part of the argument will 

 not, however, interfere with his appreciation of the 

 abilitv with which the author has conducted his 

 inquiry and of the stimulating manner in which he 

 has presented his results. T. P. N. 



DESCRIPTION OF XEW MINERALS. 

 Second Appendix to the Sixth Edition of Dana's 

 System oj Mineralogy. By Edward S. Dana and 

 William E. Ford. Pp. xii+114. (New York: 

 John Wiley and Sons; London : Chapman and Hall, 

 Limited, 1909.) Price 6s. 6d. net. 



THE debt of gratitude that mineralogists, and, 

 indeed, all interested in the physical and 

 chemical characters of the inorganic products of 

 nature, owe to the Danas, pere et fils, is immense, 

 and can scarcely be realised owing to the human 

 propensity to take for granted all that is provided to 

 hand. The task of compiling such a compendium is 

 without ending. Mineralogy, like all branches of 

 science, does not stand still, and no sooner has an 

 edition appeared than it begins to need expansion and 

 revision. The larger a work of this character 

 becomes, the greater is the difficulty in bringing out 

 fresh editions at short intervals ; yet something must 

 be done if pace is to be kept with the growth of 

 mineralogical science. In the present instance the 

 problem has been solved by the issue of a series of 

 appendices. The last edition, which was the sixth, of 

 the "System of Mineralogy," was produced by Prof. 

 E. S. Dana in 1892 ; the first appendix was issued in 

 1899, and now, ten years later, the second appendix 

 has appeared- 



In the present volume the same plan has been 

 followed as in the first appendix. It opens with a 

 list of the principal works that have been published 

 within the period dealt with, and a list of new 

 mineral species classified according to the arrange- 

 ment of the system. The rest of the book is occupied 

 with a concise but complete description of the im- 

 portant characters of the new minerals, such as the 

 crystallographical and optical constants, the values of 

 the principal angles, the colour, the specific gravity, 

 the chemical composition and the response to the 

 NO. 2088, VOL. 82] 



ordinary reagents, and the locality whence they were 

 obtained ; and, further, with an abstract of work 

 that has been done on species previously known. The 

 alphabetical arrangement renders it easy to look up 

 any species, and the reference to the original paper, 

 which is in all cases given, enables the information 

 to be traced to the source. We regret to learn from 

 the preface that the continuous strain proved too 

 much for Prof. Dana, and his breakdown in health 

 nearly three years ago compelled him finally to relin- 

 quish the work. Fortunately he had at hand a 

 colleague, Prof. Ford, who was able to complete it 

 for him. Lack of time, however, prevented the 

 course, followed in the "System" and in the first 

 appendix, of re-calculating from the data the crystallo- 

 graphical constants and the important interfacial 

 angles being strictly adhered to. 



The rate of discovery of new mineral species shows 

 no sign of abatement, contrary to what might have 

 been expected. The present volume includes about 

 sixty definitely new species. It would, indeed, appear 

 as if any careful search in new or little-known 

 localities could not fail to be fruitful in bringing to 

 light new species. Thus this volume includes de- 

 scriptions of the interesting results of Dr. Flink's 

 collecting trip to Greenland, many of Mr. Solly's 

 remarkable discoveries in the famous Lengenbach 

 quarry near Binn, the new mercury minerals from 

 Terlingua, and the curious zinc phosphates from the 

 Broken Hill mines, Rhodesia. G. F. H. S. 



OUR BOOK SHELF. 



Principles of Reinforced Concrete Construction. By 

 F. E. Turneaure and E. R. Maurer. Pp. x + 429. 

 Second edition, revised and enlarged. (N'ew York : 

 John Wiley and Sons ; London : Chapman and 

 Hall, Ltd., 1909.) Price i^s. 

 Ix this edition a considerable number of changes have 

 been made, and much new material has been added. 

 In every case records of experiments have been 

 brought right up to date : this is especially the case 

 in regard to the adherence between the concrete and 

 the reinforcing metal, to the shear strength of beams, 

 and to the strength of columns. The properties of 

 concrete and steel are fully dealt with in chapter ii. 

 The important question of the value of the modulus 

 of elasticity of concrete is discussed in the light of 

 the most recent experiments. The authors are of 

 opinion that for most calculations in regard to 

 strength the value of the modulus should be taken 

 as 2,000,000 lb. per sq. in. The tests on bond by Mr. 

 W'ithev seem to show that the intensity of the bond 

 per square inch is not affected by the size of the bars, 

 and that the average bond strength as determined by 

 direct tension is much higher than in the case of 

 beam experiments. The difficulty of carrying out these 

 latter tests prevents their more usual adoption. In 

 determining the strength of reinforced-concrete beams, 

 the authors have wisely, for the greater part of the 

 book concerned with tfiis problem, assumed that the 

 stress-strain curve for concrete is practically straight 

 within the limits of the working stresses adopted in 

 practice ; in sections 60 to 70 they have, however, de- 

 duced a series of flexure formulae on the assumption 

 that the stress-strain curve is a parabolic arc. In both 

 cases the concrete is assumed not to take any tension. 

 Engineers engaged in structural work involving the 



