July 1 8, 1878] 



NATURE 



299 



Such a superiority is less obvious than usual in Dr. 

 Spengel's production. Either Dr. Spengel was gene- 

 rously unwilling that the difference should be too striking, 

 or Prof. Huxley's malign influence has extended to the 

 German engraver and printer. 



Considering the view which the translator appears to 

 take of Huxley' s " Manual," we were rather surprised 

 that he should jeopardise his great reputation by under- 

 taking the translation of so inferior a work. Our astonish- 

 ment may easily be imagined on finding ort the back of 

 the work that the authorship is attributed to Spengel as 

 well as to Huxley. The outside of the book, as seen on 

 the book-shelf, reads thus : — 



HUXLEY-SPENGEL 

 Anatomie 



DER 

 WIRBELLOSEN THIERE. 



The only explanation which occurs to us of this unusual 

 blending of the names of author and translator is that 

 Dr. Spengel felt that the prominence of his name was 

 necessary in order to ensure, for the production of so 

 feeble an anatomist and so imperfect a writer as Prof. 

 Huxley, a circulation large enough to bring about the 

 pecuniary result for which the translation was made. 

 Men have been known to make translations for the sake 

 of a sort of parasitic, or rather "commensal" reputa- 

 tion; but in this case, since Dr. Spengel seems to be the 

 superior of Prof. Huxley, some other object must have 

 been foremost in view. 



Seriously speaking, we hardly think Dr. Spengel can 

 have fully realised the effect which such a preface would 

 have upon the ordinary reader. Had he done so his 

 behaviour towards Prof. Huxley would have been of a 

 kind for which we should hesitate to use adjectives 

 adequately descriptive. F. M. B. 



MERRIMAN'S ''METHOD OF LEAST 

 SQUARES" 

 Elements of the Method of Least Squares. By Mansfield 

 Merriman, Ph.D., Instructor in Civil Engineering in the 

 Sheffield Scientific School of Yale College. (London : 

 Macmillan.) 



THE method of least squares has an extensive litera- 

 ture of its own. Our author, in a sketch appended 

 to his work, gives the titles of forty-seven of the most 

 important memoirs and books which treat of this subject 

 and of the law of errors of observation. He further " takes 

 the wind out of the sails " of his reviewers by saying : " It 

 would be easy to greatly extend the limits of this list. The 

 titles have, in fact, been selected from a list of about four 

 hundred, which I hope some time to publish, accompanied 

 by historical and critical notes." Though this is an 

 unkind cut, inasmuch as a reviewer will hardly care to 

 bring forward any references of his own, we yet trust Dr. 

 Merriman will be sufficiently encouraged to bring out 

 this promised contribution to the history of a particular 

 branch of mathematics. The writer's objects are "to 

 present the fundamental principles and processes of the 

 method in so plain a manner and to illustrate their appli- 

 cation by such simple and practical examples as to render 

 it accessible to civil engineers who have not had the 

 benefit of extended mathematical training ; and secondly, 



to give an elementary exposition of the theory which 

 should be adapted to the needs of a large and constantly- 

 increasing class of students." Hence the book is both a 

 practical and a theoretical one. The first part is con- 

 cerned with the adjustment and comparison of engineering 

 observations in which, after giving an introduction on the 

 principles of probability and the method of least squares, 

 he treats of direct observations upon a single quantity 

 and independent observations upon several quantities, 

 conditioned observations, and the discussions of physical 

 observations. 



The second part is devoted to the theory of least 

 squares and probable errors ; in this, after a deduction of 

 the fundamental principles, he proceeds to the develop- 

 ment of practical methods and formulse. 



In an Appendix he gives Gauss's method of solving 

 normal equations, a list of literature (referred to above), 

 remarks on the theory of least squares, and a few other 

 short notes. A full index is given at the end. There is 

 frequent evidence that the writer has carefully consulted 

 the memoirs he cites in his list, so that while there is 

 nothing of novelty in his treatment that treatment is 

 founded upon the best authorities. 



" As I have not written for mathematical experts, they 

 will doubtless find considerable {sic) in the book at which 

 to gamble." He points out what may be considered 

 blots in his book. One is that he has adopted Gauss's 

 development of the law of probability of error as the 

 best adapted to an elementary presentation ; " If this be 

 objected to as defective, I claim at least the credit of 

 knowing and of pointing out just what and where those 

 defects are." 



A consequence, perhaps, of having the work printed in 

 this country is the list of errata. We would suggest in 

 the event of the publication of the historical list, that 

 the dates of reading of the memoirs should be given 

 rather than (or at any rate in addition to) the dates of 

 their publication. 



We welcome this work as an evidence of the increasing 

 attention that is being given to mathematics by the 

 author's fellow-countrymen, and hope he will be en- 

 couraged by its reception here to follow up its publication 

 with a promised work containing extended applications of 

 the method to higher geodetic surveying and the other 

 problems to which it can be and has been applied. 



OUR BOOK SHELF 



Holmes' Botanical Note-Book, or Practical Guide to a 

 Knowledge of Botany. By E. M. Holmes, F.L.S., 

 Curator of the Museum of the Pharmaceutical Society 

 of Great Britain, late Lecturer on Botany at West- 

 minster Hospital. (London : Christy and Co., 1878.) 



From the author's experience at the Pharmaceutical 

 Society, together with that gained during the time he 

 held the lectureship at Westminster Hospital, he is 

 likely to know pretty well the requirements of the 

 students at the pharmaceutical and medical schools. It 

 is not always, however, that a teacher, well acquainted 

 though he may be with what is wanted by the students, 

 is capable of providing the best material to supply those 

 wants. In this note-book we think Mr. Holmes has 

 succeeded in smoothing the path of the botanical course, 

 often so uninteresting and consequently amounting to 

 drudgery to many a student. The plan adopted of 



