760 THE POPULAR SCIENCE MONTHLY. 



the idea among insects ; and developments in anthropology teach 

 that savages depend solely for directions upon a skillful use of the 

 external signs of Nature. 



All this may be true. It still remains an utter impossibility 

 that a homing pigeon can return from a distance of over a thou- 

 sand miles if unaided by some special " sense of direction." Such a 

 view is rarely held by a practical pigeon fancier. He knows too well 

 how many birds he loses, even with most careful short-distance 

 training. He has observed that his birds, until they have learned 

 the country, generally consume time enough to enable them to 

 hunt over mile by mile a vast area, and that they can do nothing 

 in a fog or snowstorm, or if blindfolded or hooded. Twenty years 

 ago Leonard * wrote as follows : " Some writers, chiefly poets and 

 romancers, would have us believe that the carrier pigeon finds his 

 way home from remote places by a kind of instinct ; but this is 

 not the case. Its flight is guided by sight alone. When let loose 

 from confinement, it rises to a great height in the air by a series 

 of constantly enlarging circles until it catches sight of some famil- 

 iar landmark by which to direct its course." 



Had " poets and romancers " continued sole occupants of the 

 field, the following notes would have served no other than the 

 private purpose for which they were taken, f As it is, a number 

 of attempts have recently been made by men of high scientific 

 attainments to prove theories of " direction-sense " by feats of the 

 homing pigeon. In general, such attempts are made in line with 

 one or the other of two assumptions. According to the one, " di- 

 rection-sense " is ascribed to some mysterious, direct, and imme- 

 diate perception or sensation of location or direction in space. 

 More often it is supposed to be a sort of " dead reckoning" which 

 the organism has become able to keep that is, the animal has 

 come to have a feeling, definite or vague, as to how long, how fast, 

 and which way it has traveled or has been carried. Two papers 

 may be cited as giving possibly the best expositions of these two 

 views. The one by Prof. Exner J adduces evidence to prove the 

 " dead-reckoning " theory ; the other, by Prof. Caustier,* attempts 

 to establish that of immediate perception. Both agree as to the 

 organ viz., the membranous labyrinth, especially the semicircu- 

 lar canals. 



There is nothing impossible about Exner's explanation. All 



* E. B. Leonard. Pigeon Voyagers. Harper's Monthly, vol. xlvi, p. 659, 1873. 



f My own experiments related to a study of extreme fatigue of the nervous system, and 

 for this purpose homing pigeons were furnished me by the generosity of Dr. S. Weir Mitch- 

 ell. It thus became necessary, in order to credit accurately the amount of effort put forth 

 in any given instance, to observe their habits and methods of flight. 



| S. Exner. Das Rathsel der Brief tauben. Wien, 1892. 



* E. Caustier. Les Pigeons Voyageurs. Revue de PHypnotisme, July, 1892, p. 10. 



