32 



KNOWLEDGE. 



January. 1915. 



extent to which it has modified the landscape over vast 

 tracts of country, should have sprung into existence is 

 small matter for wonder ; and it is particularly satisfactory 

 that the author has been at great pains, as the result of 

 his large personal experience, to get at the truth in 

 such cases. 



One of the points in dispute is whether beavers plaster 

 over their " lodges " (i.e., their dwelling chambers) wdth 

 mud dredged from the bottom of the pools in which they 

 are built. Some observers have stated that the lodges 

 are roofed only with sticks ; but, although he admits that 

 this is often the case in the earlier part of the season, Mr. 

 Dugmore states that in most cases which ha\'e come under 

 his own observation they are thickly daubed at the com- 

 mencement of winter with mud, which is, of course, soon 

 frozen hard. Verv remarkable is the statement that a 

 beaver's couch of wood-fibre in the lodge is always kept 

 perfectly dry, despite the fact that the owner has to effect 

 an entrance under water, thus indicating that the animals 

 must have some means of drying themselves before resorting 

 to their beds. 



Far more extraordinary is, however, the author's theory 

 that beavers designedly construct a ventilating apparatus 

 in the lodge, either in the form of a thin patch in the roof 

 or, when the structure is built round a tree, in the shape 

 of a chink at the junction of the roof with the latter. " The 

 very idea of making pro\asions for ventilation," remarks 

 Mr. Dugmore, " is one of the many exhibitions of the clever 

 animal's thoughtfulness. The e.xistence of these ventilation 

 flues has sometimes been questioned, but it has been more 

 or less clearly exhibited in all of the many scores of lodges 

 which I have examined." That such apertures do exist 

 may be freely admitted, but tliis is far from con\'incing 

 us that the beaver constructs them \\-ith a definite knowledge 

 of their effect as ventilators, more especially when we recall, 

 as the author mentions, that the beaver's brain is of a low 

 type, even for a rodent. 



Such psychological opinions do not. however, in any 

 wav detract from the general excellence and interest of 



this beautifullv illustrated volume, which we may con- 

 fidently recommend to the best attention of our readers. 



R L. 



Zoological Philosophy. — By J. B. Lamarck. Translated, 



with an introduction, by Hugh Elliot. 410 pages. 

 9-in. X 6-in. 

 (Macmillan & Co. Price 15/- net.) 



It is surprising how long it often takes for_a mistake to 

 be corrected owing to one author copying from another, 

 and half-truths are liable to be handed down for an even 

 longer time, especially when they refer to a man's opinions. 

 This is because in our days of hurry few have the time or 

 take the trouble to read what was originally written, 

 particularly when the words belong to a foreign language. 



Now that Mr. Hugh Elliot has translated Lamarck's 

 " Zoological Philosophv," and written an introduction 

 which is a valuable summary of the views expressed in it, 

 there is really no ,pxcuse for anyone to look upon Lamarck 

 merely as a zoologist who believed, what few do now, 

 that acquired characters are inherited. Mr. Elliot would 

 be the last to deny that Lamarck considered the inherit- 

 ance of acquired characters to be one of the main 

 factors of evolution, but the fame of Lamarck depends 

 upon the fact that he believed in evolution fiftr\' years 

 before Darwin's " Origin of Species " appeared, and, 

 further, to use Mr. Elliot's words, " he defended the doctrine 

 of organic evolution at a time when it was opposed, not only 

 to the entire authoritv of the Church and people, but also 

 to the judgment of the leading men of science. For half a 

 centurj-, his writings stood as almost the only public repre- 

 sentation of a belief which no one now questions." 



After giving a most interesting account of Lamarck's 

 life, Mr. Elliot re\dews his zoological work, goes into details 

 as to his ideas on evolution and the advances he made in 

 classification, and discusses liis physiology and psychology'. 

 We have also to thank Mr. Elliot for gi\'ing us a literal 

 translation of the " Zoological Philosophy," and at the same 

 time for breaking up some of his ponderous sentences. 



W. ]\L W. 



NOTICES. 



OUR MICROSCOPICAL COLUMN.— We have great 

 pleasure in announcing that in future the Microscopical 

 Column in " Knowledge " will be conducted by Mr. J. E. 

 Barnard, F.R.M.S. 



CLASSES IN PHOTOGRAPHY.— Mr. Edgar Senior's 

 classes in photography begin again on Tuesday-, January 

 12th, 1915, at the Battersea Polytechnic, and on Monday, 

 January 11th, at the South Western Polytechnic. 



GEOLOGICAL AND MINERALOGICAL BOOKS.— 

 Messrs. John Wheldon & Co. have issued a classified 

 catalogue of second-hand books, to the number of nearly a 

 thousand, dealing with mining, geology, and palaeontology. 

 It is so arranged that the titles of works dealing with any 

 particular subject can be read through at once. 



NATURAL HISTORY PHOTOGRAPHY.— We have 

 received a catalogue from Mr. Armytage Sanders, which 

 reminds us that he is still supphnng his special cameras 

 for natural history photography from 26, Charing Cross 

 Road. He also undertakes all kinds of photography, 

 lantern-slide making, and caters for the requirements of 

 lecturers. 



FOREIGN BOOKS ON SCIENCE.— We learn from 

 Nature that arrangements have been made whereby books 

 published outside the LTnited Kingdom which are re\'iewed 

 in its columns shall be on view at the offices of that paper, 

 St. Martin's Street, W.C, for six months (after the re\aews 

 have appeared) freely to anyone who cares to call and see 

 them. The step has been taken owing to enquiries that 



are continually being received, and it is hoped that many 

 men of science will welcome the opportunity thus afforded 

 to them. 



SECOND-HAND INSTRU.MENTS.— The sale of second- 

 hand apparatus by !Mr. C. Baker has now reached such an 

 importance that it has been found necessary to separate 

 that dealing with photographic work from the rest. The 

 present issue of the classified list still, however, contains 

 ten sections, and describes instruments and accessories 

 used in microscopy, surveving, astronomy, and advanced 

 physical research. Field glasses and books are also included, 

 and a list is added of instruments and apparatus wanted in 

 the various sections. 



FLIGHT - LIEUTENANT LAN - D.WTS. — FUght- 

 Lieutenant C. F. Lan-Davis, who is a director of Messrs. 

 J. H. Dallmeyer, Limited, well known to our readers as 

 the makers of photographic and cinematograph lenses, 

 has had a lucky escape from drowning. We learn from the 

 Daily Chronicle that, while fljdng about ten miles from 

 Y'armouth, liis aeroplane, wliich is attached to Yarmouth 

 Air Station, was completely smashed up through the bursting 

 of the engine. The aeroplane dropped into the sea, and the 

 North Shields drifter " Noreen " saved the lieutenant 

 and his mechanic, Hendry, bringing them to Crossley Hos- 

 pital, Yarmouth. When the aeroplane fell, Hendrj' swam 

 clear, but Flight-Lieutenant Davis was unable to do so, 

 being strapped in his seat. Hendrv', however, gallantly 

 dived underneath the aeroplane and unstrapped the airman, 

 who was rescued only just in time by the " Noreen 's " 

 boat. 



