April 13, 191 1] 



NATURE 



211 



'Ihe Gyroscope: An Experimental Study. From 



Spinning-Top to Mono-Rail. By V. E. Johnson. 



Pp. 52. (London : E. and F. N. Spon, Ltd. ; New 



York: Spon and Chamberlain, 1911.) Price is. 6d. 



net. 

 This is an admirable little book suitable from every 

 point of view as a present for a boy with a mechanical 

 turn of mind. As the extended title indicates, the 

 properties of the gyroscope are illustrated by a series 

 of experiments, always with a view to its application 

 to a mono rail car. The reader is expected to be able 

 to drill holes in metal and tap threads in them and 

 perform simple constructional operations. He is thus 

 encouraged to prepare his own apparatus and make 

 each experiment as he goes along". 



The originality of some of the experiments and the 

 conclusions to be drawn from them, the home-made 

 gyroscope, with the flywheel of a sewing machine as 

 centre feature, and the general scheme of the book 

 are all excellent, and any boy who works through the 

 examples will find himself imperceptibly acquiring the 

 gyroscopic sense, and he will greatly enjoy the pro- 

 cess. One of the later devices illustrated is an elec- 

 trically-driven monorail and gyrostat, for further de- 

 tails of which the reader is referred to the number 

 of The Model Engineer in which it was first described. 

 No doubt this is the apparatus that was shown at 

 work at the last exhibition organised by The Model 

 Engineer. C. V. B. 



Simple Lessons in Nature Study. By J. O'Neill. 



Pp. 122. (London : Blackie and Son, Ltd., n.d.) 



Price IS. net. 

 This book comprises about twenty-five lessons on 

 plant characters and ten referring to animals ; buds, 

 the work of leaves, the dandelion, birds, the hedge- 

 hog, talks on tadpoles, are a few of the subjects dis- 

 cussed. It has been prepared for the use of teachers; 

 as such it has no obvious merit, because it cannot be 

 said to present simple facts and natural inferences in 

 anv new light, nor does it penetrate sufficiently deeply 

 into the subject to impart the knowledge required 

 for teaching. 



Aphorisms and Reflections from the Works of T. H. 



Huxley. Selected by Henrietta A. Huxley. Pp. 



86. (London: Watts and Co., 1911.) Price 6d. 

 Messrs. Watts and Co. have issued these aphorisms 

 and reflections of Huxley for the Rationalist Press 

 Association, Ltd., by permission of Messrs. Macmillan 

 and Co., Ltd. The price at which the book is now 

 obtainable will, it is to be hoped, make Huxley's clear 

 thinking and lucid expression known to a new circle 

 of readers and send many of them to the complete 

 works from which the apothegms are selected. 



The Flight of Birds. By Giovanni A. Borelli. Pp. 



X4-40. (London : For the Aeronautical Society of 



Great Britain by King, Sell, and Olding, Ltd., 



191 1.) Price IS. net. 



We have hero a translation of the section called " De 



Volatu " in the first volume of Borelli's " De Motu 



Animalium," first published in Rome in 1680-81. 



This is the first time this part of the seventeenth- 



centurv classic has been translated into English. The 



bookl( I will make an appeal to all who are interested 



in the conquest of the air. 



Life Histories of Familiar Plants. By John J, Ward. 



Pp. xx+204. (London: Cassell & Co., Ltd., 1911.) 



Price 3s. 6d. 

 This popular edition of a book whirli appeared in 

 1908 should prove of service to ii iclni^ df n.iiure- 

 study and field botany. The ("ir^i ((liiicn was re- 

 viewed in those columns on .Ma\ .'n. \<,<i') (vol. Ixw., 

 p. 344), and the present issue remains iinciianged. 



NO. 2163, VOL. 86] 



LETTERS TO THE EDITOR. 



[The Editor does not hold himself responsible for opinions 

 expressed 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 0/ anonymous ccmtnunications.] 



The Fox and the Fleas. 

 The belief that the fox rids himself of fleas by the 

 device to which Prof. Hughes has directed attention in 

 Nature is a long-established one. This is shown by the 

 following passage from Allan Ramsay's " Gentle Shep- 

 herd," which appeared in the year 1725 : — 



"As fast as flaes skip to the tate o' woo, 

 Whilk slee tod lowrie bauds without his mow, 

 When he to drown them and his hips to cool. 

 In summer days sHdes backwards in a pool." 



The language is the variety of English which prevailed, 

 and of course still prevails, in North Britain. " Tate o' 

 woo " means tuft of wool, " slee tod lowrie " means the 

 sly fox, and " bauds without his mow," holds outside his 

 mouth. A. N. Meldrum. 



Hamilton, N.B., April 10. 



Referring to the letter of Prof. McKenny Hughes on 

 the fox and the fleas, in Nature of March 23, may I be 

 allowed to say that I heard exactly the same story, several 

 times over, in my youth, which means about fifty years 

 ago? I must confess that I thought it had ori'ginated 

 somewhere in Gascony, the home of Cyrano of Bergerac. 

 It seems now to turn out to be true. If really authenti- 

 cated, as Mr. T. Day appears to suppose it, it would be 

 worth while to make its exact authentication known, 

 as it may be looked upon as a most prominent proof of 

 reasoning on the part of an animal. 



Paris, March 24. T. S. Grey. 



Many years ago a few friends were chatting in Kirkby 

 Lonsdale Vicarage, and one of us remarked that almost 

 everybody had within his own knowledge some story that 

 he could not expect his friends to believe. The vicar 

 (Henry Ware, afterwards Bishop of Barrow) told us his 

 story. He was coming out of the vicarage with Arch- 

 deacon Evans and the parish clerk, when they saw in the 

 lime avenue in front of them a chaffinch fluttering up and 

 down with the tip of its wing attached to one of the long 

 pendulous twTgs of a lime tree. The clerk got steps and 

 a hook or something by which he pulled it down, and 

 they found that the bird's wing was stuck, as they thought, 

 by the honey dew to the leaf, while the plav of the twig 

 never let it get sufficient lateral pull to disengage it. 

 DE ANIMAL. SYLVES. 



Dc dolofo ingcnio VuJpium- 



My story was that, when I was a boy, walkiiiq lK>mi' 

 along the banks of the Bawddwr. which w.i^ ih( n Uo/ju 

 over, I saw a trout through tin; «IiMr iir ami t<.)ok a shat 

 at it with a stone. The stone made a small hole in the 

 ice, through which the trout jumped out. I thought that 

 the pressure on the ice due to the impact caused an up- 

 rush of water, which caught the trout as he darted away 

 and carried him out head first. 



It may not have been altogether the Iioitv d w that 

 stuck the bird's wing to the leaf, and tlif iip i haiiics of 

 my trout's leap may be better explained, but the stories 

 are true. 



So in the often repeated and much discussed story of 



