Jan. I, 1874] 



NATURE 



161 



in many cases obtained by calculations beyond the grasp 

 of the less advanced pupils ; and the Translators have con- 

 siderably improved what was already good by several 

 Appendices, among which one of the most important is 

 that on Thomson's electrometer. Some preliminary 

 sections are devoted to the reduction of observations 

 made with the mirror and scale to angular measure, to 

 the determination of the position of equilibrium and time 

 of oscillation of a magnetic needle and similar topics, 

 while the methods of reading the various magnetometers 

 and galvanometers, and the measurement of resistance 

 and electromotive force, are afterwards discussed. 



On the whole the principal fault we have to find with 

 the book is a want of fulness, especially in the earlier por- 

 tions. It aims at supplying a want already felt, and 

 which will become still more pressing as the number of 

 those who make some progress in the study of Natural 

 Science increases, and we are not aware of the existence 

 of any manual which gives the information contained in 

 it in an equally compact and handy form ; while the 

 tables, thirty in number, which fill the concluding pages, 

 will often save time and trouble to those engaged in labo- 

 ratory work. Although, then, as we have already 

 pointed out, we consider it capable of very considerable 

 improvement, yet probably most teachers of Experi- 

 mental Physics will obtain some useful hints from its 

 perusal, even if they do not adopt it as a text-book for 

 their pupils. A. R. 



OUR BOOK SHELF 



Plicasanis for Coverts and Aviaries. By W. B. Teget- 



meier, F.Z.S. (London I'Horace Cox. 1S73.) 

 Any work on animals which appeals to so many different 

 human weaknesses as the Pheasants, must be popular 

 if the least effort has been made to do the subject 

 justice. The one before us has merits which make it 

 peculiarly acceptable. It is by the hand of an author 

 who has devoted his life to the careful study of the na- 

 tures and habits of the GalHnaccous birds and Pigeons, 

 and who has long since made himself well known by 

 works on some of the genera, which have become the 

 standard literature of the points on which they treat. 

 In the handsome volume before us ]\Ir. J. W. Wood's 

 excellent and truthful illustrations add greatly to its 

 value, though the absence of coloration has made it more 

 than difficult in some cases to produce an approach to 

 the gorgeous appearance of some of the species depicted. 

 Among those that suffer most from this deficiency, are 

 the Japanese Pheasant {Pliaiianus versicolor), whose 

 chief beauty consists in the richness and delicacy of the 

 shades of its plumage, and the Golden Pheasant [Thaii- 

 melia pieta), with its ally, the Amherst Pheasant {T. ain- 

 itersticr), whose resplendent hues even the best artist finds 

 it difficult to represent. The Reeves' Pheasant {P. reevesii), 

 and the Eared Pheasant {Crossoptilon mantchi/ricimi), 

 however, form excellent and most truthful pictures, colours 

 in them not being such important features. Mr. Teget- 

 meier, besides describing each of those species which are 

 the love of the sportsman and the pride of the aviary, 

 devotes the earlier part of his work to the discussion of 

 points of great practical interest. After a short history of 

 the Pheasants as a family, from which it is clear that they 

 were introduced into this country from Asia Minor, the 

 native home of the common Pheasant {P. cole/iiciis), as 

 early as the reign of King Harold, and probably by the 

 Romans, a series of chapters is given on the management 

 of the bird in preserves and in confinement, together with 



an account of the diseases to v^-hich it is most liable. 

 These are replete with practical detail that must be most 

 valuable to the many who spend such large sums on pre- 

 serving game, and to those who have the actual superin- 

 tendence of the coverts themselves. Particular attention 

 is drawn to the great difference between birds, like the 

 common Fowl {Gatliis baiikiva), which are capable of 

 domestication in the true sense of the word, and the 

 Pheasants, which, though individuals are frequently 

 known to become tame, can never be really domes- 

 ticated ; even the young ones taking to the woods on the 

 earliest opportunity, whilst the opposite inherent pecu- 

 liarities of the poultry have given rise to the proverb — 

 " Curses, like chickens, come home to roost." Alto- 

 gether this work supplies a long-felt want, and its perusal 

 will well repay anyone who takes it up. 



LETTERS TO THE EDITOR 



\TIie Editor does not hold himself responsible for opinions expressed 

 by Ins corresfondents. No notice is taken of anonymous 

 communications. ] 



Wasps 



Perhaps it may be of interest to some of your readers, who 

 make entomology their study, to know that the wasps in a nest 

 about a mile from this were still tolerably active on the I3tli of 

 this month, when my attention was attracted by the loud buzzing 

 of three or four wasps at the entrance, apparently ventilating it 

 with their wings after the manner of bees. I again visited the 

 place on the 23rd. There were at first no signs of life outside ; 

 but stamping on the ground above caused a considerable number 

 to come out after a minute or a minute and a half and hover in 

 the air above the entrance. I attribute this unusual circumstance 

 to the mildness of the season (the minimum temperatures having 

 been 26° in October, 25° in November, and 29" on the loth and 

 nth of December, and the 13th having been mild, and so also 

 the 23rci) and the bad conducting power of the nearly cut out 

 peat bog in which the nest was situated. 



Birr Castle, Parsonstown, Dec. 24, 1873 RosSE 



The Potato Disease and Lord Cathcart's Prize 



No one acquainted with botanists and botanical science can 

 feel surprised at the decision of the committee in this matter, 

 and it must be confessed that, however well meant, the offer of 

 the 100/. prize was a great mistake which has only ended in pro- 

 ducing ninety-four unsatisfactory essays and the loss of a year. 



Little else could have been expected, for the Council of the 

 Royal Agricultur.il Society must surely be aware that the men 

 (in this country at least) who are competent to write anything 

 ncio on the subject could certainly be counted in units, and these 

 men could not enter into the competition for more reasons than 

 one, not If.e least being the loss of status such a proceeding would 

 entail. 



It appears to me that the committee have even now hardly hit 

 the light nail upon the head in recommending a grant of money 

 to " some competent mycologist " to investigate the life history of 

 the fungus during a certain period of its life. If the investiga- 

 tion is carried on by any one man it is sure to end iu failure. It 

 would be far better lor the committee to recommend that 

 five or six competent botanists should each write an essay 

 on the subject from his own point of view, each essay 

 to be published in the Society's journal. There are many 

 reasons why this would be best. I will give one. Payen 

 has figured and described certain ciliated bodies found in spent 

 potatoes, and which Berkeley and other botanists have looked 

 upon as the probable resting-spores of the Piionospora. Mon- 

 tagne has lefeiTed these same bodies to the Sepcdoniei, whilst I 

 am by no means sure that the objects do not belong to the Stil- 

 bacci, and are no other than Voltitella ciliata. However this may 

 be, I have met wdth the last in spent potatoes in immediate con- 

 nection with \he Peronospora itself. Where competent observers 

 differ in opinion it is better to get the views of all. It would be 

 very unwise to restrict the observations to any particular period 

 o( the growth of the plant, and very little would be added to our 

 knowledge were the resting spores themselves found; ior, resting 

 spores orno resting spores, it is an ascertained fact that the living 



