September 14, 191 1] 



NATURE 



35i 



yard or two the position of his boundary, and made 

 the fact quite clear to any other robin who did not. 

 Moreover, the author found that it was not easy to 

 drive them out of their own little estate, to which they 

 invariably returned immediately. 



The intention of making life habits the chief feature 

 in the work is fully carried out in the last two sec- 

 tions. A notice inserted in the last part informs 

 readers that in order to render the notes on Distribu- 

 tion more complete, the range of each species outside 

 its breeding area will be briefly indicated. 



Mr. A. \V. Seaby's pictures are as charming, 



spirited, and lifelike as ever — quite the most original 

 and refreshing bird pictures we have seen for long — 

 and there are excellent plates of the rosy pastor, 

 golden oriole, and waxwing by some of the other 

 artists who contribute to the work. 



-1 MONUMENT TO JANSSEN. 

 A N influential committee has been formed to raise 

 **- to the memory of Janssen a durable monument 

 which shall recall to the minds of those who see it the 

 enormous and brilliant services rendered to astronomy 

 by the great French savant. 



A man <i| rare breadth of mind, it was not simply 

 to any one branch of the oldest science that Janssen 

 turned his attention, but he will be remembered chiefly 

 for his fruitful researches in astronomical physics. 

 That brilliant discovery, shared by Lockyer, in 1868, 

 will probably be the lucida of his labours, the method 

 of observing solar prominences, of drawing and mea- 

 suring those enormous solar flames, without waiting 

 for the rare and uncertain seconds of a total solar 



no. 2185, vol. 8;] 



eclipse. Only those whose work it is to observe and 

 to study solar phenomena know how much of our 

 present knowledge is due to the timely discovery of 

 (hi- method. By this have the labours of the dis- 

 coverers, of Respighi, of Young, of Tacchini, Ricco, 

 Hale, and Deslandres, and of many others become 

 productive. Janssen from India and Lockyer from 

 West Hampstead sent messages to the French 

 Academy which arrived almost simultaneously, and 

 immediately a new era in the rapidly expanding 

 knowledge of the sun's physical and chemical attri- 

 butes was opened. 



Janssen also studied with great assiduitv and 

 marvellous results the laws of the absorption and 

 transmission of light travelling through gaseous 

 media, and thereby laid foundations on which have 

 since been erected wonderful superstructures. As an 

 organiser he was in the forefront. His photographs 

 of the solar surface were magnificent and have never 

 been excelled. It is to Janssen that we owe the estab- 

 lishment of the solar observatory on Mont Blanc, 

 whither, in spite of his lameness, he made many 

 ascents. 



All this will count as an imperishable monument to 

 those who know aught of astronomical physics. 

 We heartily sympathise with the aims of the 

 committee which has charged itself with receiving 

 subscriptions to this end, and below give the 

 names of those who have already joined: — MM. 

 Armand Gautier, president de l'Academie des 

 Sciences; G. Lippmann, vice-president; G. Darboux, 

 secretaire perpetuel ; Ph. Van Tieghem, secretaire 

 perpetuel; C. Wolf, doyen de la Section d'Astronomie; 

 Henri Poincare, de l'Academie Francaise ; G. 

 Bigourdan, de ITnstitut ; J. Violle, de l'Institut; B. 

 Baillaud, directeur de l'Observatoire de Paris; Prof. 

 Chauveau, de l'Institut; De Selves, prefet de la 

 Seine; Daumet, de l'Institut; Edmond Perrier, 

 directeur du Museum; Prof. Bouchard, de l'Institut; 

 Alfred Grandidier, de l'Institut; Prof. Lannelongue, 

 Senateur; Dr. Roux, directeur de l'Institut Pasteur; 

 R. Radeau, de l'Institut; G. Lemoine, de l'Institut; 

 H. Deslandres, directeur de l'Observatoire de 

 Meudon ; M. Hamy, de l'Institut; P. Puiseux, 

 astronome a l'Observatoire de Paris. 



PIERRE EMILE LEVASSEUR. 



BY the death of Pierre Emile Levasseur both geo- 

 graphy and economic science in France have 

 sustained a severe loss. Born on December 8, 1S28, 

 Prof. Levasseur devoted his energies during a long 

 life to demonstrating the importance of a right appre- 

 ciation of geography in its application to man and 

 of economic science. As early as 1863 he published 

 a " Precis d'Histoire de France " and a " Precis de 

 G6ographie," and throughout many years of active 

 work in economic geography he always aimed at the 

 highest precision in his studies with the view of build- 

 ing up a truly scientific type of geography and insist- 

 ing upon the educational value of the subject when so 

 treated. He especially directed his efforts towards a 

 thorough understanding of the economic geography 

 of France, but he also travelled widely in order to 

 study economic conditions occurring in other lands; 

 a journey to the United States in 1853 resulted in 

 an important work, " L'Ouvrier AmeYicain," and the 

 same line of investigation, followed up both his- 

 torically and economically, produced important studies 

 on the working classes in France up to the time of 

 the Revolution, and a later work dealt with their 



