May 1 6. 1901] 



NA TURE 



53 



like that of the female. Young males appear to have a 

 more powerful syrinx than adult females. 



The chapter dealing with the development of song and 

 other forms of display are full of thoughtful matter. 

 Special mention is given to Rohweder's recent interpre- 

 tation of the curious bleating or drumming of the snipe. 

 This observer contends that this strange music is caused 

 by the rapid vibration of the horizontally e.\tended and 

 half-closed wings, which drive a strong current of air 

 against the stiffened outer tail feathers, setting them in 

 rapid vibration, and causing the curious tremulous 

 bleating sound. This explanation differs somewhat from 

 that of Meeves and others, and is probably the most 

 nearly correct explanation we have yet had. 



We heartily commend the book to the notice of 

 ornithologists. W. P. P. 



Physikalisch-chcinische Propiideiitik. Zweite Halfte, 1-3 

 Lieferungen. \'on H. Griesbach. (Leipzig : W. Engel- 

 mann, 1896-1900.) 



This book, the first part of which has already been 

 reviewed in N.\ture, is chiefly intended for those inter- 

 ested in medical science. In it Prof. Griesbach dis- 

 courses of everything from the law of gravitation and 

 the conception of potential to the chemical nature of dis- 

 infectants and the morphology and physiology of bacteria. 

 There is no particular arrangement in the book ; chapter 

 xxiii, on molecular mixtures, occupies 232 pages, whilst 

 chapter xxiv, on the factors of energy, occupies 4. It must 

 not be supposed, however, that the book is on this 

 account uninteresting — far from it ; it is excellent read- 

 ing, and is both wonderfully accurate and wonderfully 

 complete. Indeed, the struggle after completeness seems 

 to be the author's chief failing. In connection with semi- 

 permeable membranes, he happens to mention sugar. 

 This at once prompts him to give the means of detecting 

 sugar : — smell of caramel, " French word from Latin 

 canna inellis, honey-cane, i.e. sugar cane," and reduction 

 of Fehling's solution, which necessitates a short biography 

 of Fehling. Exact instructions for the preparation and 

 use of Fehling's solution are then given. This, of course, 

 involves reference to Rochelle salt, whence " Pierre 

 Seignette, born when and where ? physician and apothe- 

 cary in Rochelle, died at Rochelle, 11 March, 1719." 

 After nearly two large and closely printed pages we get 

 back once more to semipermeable membranes. This is 

 propaedeutic with a vengeance. 



Despite its faults of method the book is a mine of 

 valuable information, and can be cordially recommended 

 to any medical man with a taste for the physical 

 sciences. 



Annals of Politics ,tiid Culture (1492 -1899). By G. P. 

 Gooch, M.A., with an introductory note by Lord Acton. 

 Pp- 53°- (Cambridge : University Press, 1901). Price 

 ys. bd. net. 



The object of this work, as set forth in the preface, 

 may at first -sight appear pretentious and impossible of 

 achievement, viz., to present " a concise summary of 

 modern times, embracing the life of mankind in its entire 

 range of thought and action.'' As soon, however, as the 

 reader has mastered the plan of the book it will be found 

 that the author has carried out his object — originally 

 suggested by Lord Acton — with remarkable skill and 

 completeness. Politics occupy the left and culture the 

 right hand series of pages. At the top corner of each 

 page is the date in conspicuous type, and a further sub- 

 division under the two headings enables the reader to pick 

 out at once the particular subject or country. The poli- 

 tical subjects are classified under countries and the culture 

 subjects under various headings, such as art, science, 

 philology, history, philosophy, literature, education, eco- 

 nomics, archaeology, social, deaths, &c. Of course it is 



NO. 1646, VOL. 64] 



the scientific references that will chiefly appeal to our 

 readers, and so far as we have tested these they appear 

 to be both accurate and complete. The author has evi- 

 dently been well advised in his choice of scientific events 

 and due proportion as to the relative importance of dis- 

 coveries in different branches of science which, under a 

 chronological classification, have necessarily to be 

 brought into juxtaposition, has on the whole been care- 

 fully observed throughout the long period of more than four 

 centuries covered by the work. A very complete index, 

 composed both of names and subjects, is correlated with 

 the contents of the volume by reference numbers and 

 not pages, ordinary numerals referring to politics and 

 italicised numerals to culture subjects. As a book of 

 reference, workers in the history of science will find 

 Mr. Gooch's volume of great value. R. M. 



The Child: His Nature and Nurture. By VV. B. 

 Drummond. Pp. 146. (London : J. M. Dent and 

 Co. ; no date.) Price, \s. net. 



In the preface of this primer it is stated that the book is 

 intended as an introduction to the study of the physical 

 and mental development of the child, and it is admirably 

 fitted for this purpose. It covers a wide range, but is 

 concise, clear and interesting, and brings within a small 

 compass the result of recent work in the study of chil- 

 dren. It is a book which should be in the hands of 

 every one who has to do with children, and besides being 

 a practical help in dealing with the infant and growing 

 child, we think it will stimulate further child-study. 



LETTERS TO THE EDITOR. 



[The Editor does not hold himself responsible for opinions ex- 

 pressed by his correspondents. Neither can he undertake 

 to return, or to correspond with the writers of rejected 

 manuscripts intended for this or any other part of Nature. 

 No notice is taken of anonymous communications,^ 



The Smithsonian Solar Eclipse Expedition. 



The Smithsonian Institution lias sent out a small party to 

 Sumatra, under the immediate charge of Mr. C. G. Abbot, to 

 continue certain of the observations described in Nature of 

 July 12, 1900, where these, on account of the narrowness of the 

 eclipse track and the brevity of the time, were indeterminate. 



The expedition sailed on February 16 in the Government 

 transport Sheridan, and the Institution has learned of the 

 arrival of the party at Padang, Sumatra, on the General 

 Alava, a United States naval vessel. 



The objects principally sought are, such a thorough photo- 

 graphic search in the neighbourhood of the sun, for possible 

 intramercurial planets, as may be apt to set the question of their 

 existence at rest ; and also a further and more complete study, 

 by the bolometer, of the heat of the corona. 



The observations of May 1900 were three in number : — 



(1) One on the radiation from the screen. This was arbitrary 

 and may be called zero. 



(2) One on the dark moon, giving on the millimetre scale 



- 18, showing that the bolometer was radiating to the moon. 



(3) One on the inner corona, giving - 13, showing that the 

 bolometer was radiating to it, though in a less degree than to 

 the moon. 



The algebraically increased reading for the coronal radiation 

 then (-l3-(-lS)= -1-5) was probably due to this coronal 

 radiation, together svith possibly something from the different 

 radiations of the closely neighbouring parts of the sky used in 

 the two observations. 



Since the Wadesboro experiments the bolometer has been set 

 on a screen of its own temperature, giving zero ; on the bright 

 moon, giving -fSS, and on the night sky near the moon, giving 



- 30. 



From my study of the visual photometric observations made 

 at Pike's Peak in 1878, and at other places, it appears that the 

 average visual brightness of the portion of the corona covering 

 the bolometer at Wadesboro was approximately equal to that of 

 the full moon. 



I infer, then, that the full moon being of the average brightness 



