Recent Ornithological Publications. 517 



are far more simple than they probably are. He then describes 

 a machine by which he satisfied himself of the correctness of his 

 views, and obtained some of his data (for the calculation of which 

 he gives a sketch), leading him to the marvellous conclusion that 

 it requires the force of one horse-power to raise a weight of 

 30 lbs. by the action of wings. Consequently a Pigeon weigh- 

 ing I lb. exercises the sixtieth part of a horse-power in rising, 

 and a Lsemmergeier of 15 lbs. employs half a horse-power. He 

 says nothing about the rapidity with which this expenditure 

 of energy would enable the birds to rise, but implies that no 

 smaller force would permit them to do so — all of which it is 

 needless to refute. Mr. Krarup-Hansen would appear not to have 

 thoroughly mastered the difficult subject of the dynamics of mo- 

 tion in a resisting medium ; it is therefore not very easy to follow 

 the steps by which he arrives at his conclusion ; but we take 

 leave to question altogether one of his assertions. *' It is not 

 seldom,^^ he says (p. 7), " we hear the wings of pigeons^ rising 

 into the aii-, strike together beneath and, though more rarely, 

 above the body of the bird." That the wings strike together 

 above, almost every Pigeon-fancier knows ; but that they ever do 

 so beneath is more than doubtful. On the whole, we may say 

 that the author, having assumed an entirely imaginary method 

 of flight, proceeds to reason very fairly on his premisses — but 

 these being (as we imagine) false, his argument comes to the 

 gi'ound. 



7. Saviss. 

 We are much obliged by the receipt of the second part of the 

 second volume of the * Bulletin de la Societe Ornithologique 

 Suisse,' which contains an excellent Bibliography of Swiss Orni- 

 thology by Dr. Carl Stoelker, giving the titles of more than 130 

 separate publications or papers connected with the subject, 

 besides references to a vast number of mostly shorter notices, 

 the whole being the work of nearly 120 authors. Besides this, 

 there is an interesting essay by M. Jean Saratz on the Birds of 

 the Upper Engadine, which may be -read in connexion \(\i\\. the 

 remarks of Dr. Baldamus published in 1867 (Zeitschr. gesammt. 

 Naturwiss. Ivi. pp. 99, 10,0), and then a paper communicated 

 by M. Victor Patio, with the chief points of which our readers 



