158 Prof. F. O. Guldberg on Movement in a Circle 



while the guiding sense is blinded, movement passes into the 

 pliysiological circular direction, and it returns to the light. 

 The constant repetition of these circles, until the birds often 

 drop exhausted near the lighthouse, as well as the apparently 

 disturbed state of mind of the animals when they are flying 

 and swimming round and round, in our opinion also support 

 such an explanation of this phenomenon. Mention may also 

 be made of the circling flight of the willow-grouse and 

 capercailzie, well known to the Scandinavian peasant-gunners 

 who lie in wait for these birds, in which the instinct of locality 

 alluded to above seems to appear, just as a similar instinct 

 seems to prevail in beasts of prey during the pursuit of game. 

 But the best illustrative evidence in favour of these biological 

 circles is furnished by inammals, which more frequently come 

 into contact with man either as domestic animals or as objects 

 of the chase. — The lecturer here produced in explanation of 

 his statement a series of graphic charts, which were sent to 

 him by the foremost sportsmen in the country (Norway) ; 

 these charts show that the course taken by hunted animals 

 (hares and foxes) when pursued by the hounds exhibits over 

 and over again tlie curve of a biological circle. This applies 

 especially to hares, for the circles, or " Turen," as Norwegian 

 sportsmen call them, described by these animals can often be 

 distinctly followed from one end to the other, since it is only 

 paths, high roads, the animal's own track, defiles, and insur- 

 mountable natural obstacles, or sudden interruptions due to a 

 rencontre with hunter or hound, that produce changes in, or a 

 cessation of, the biological circular course. 



From these charts of circular runs it is also to be seen how 

 the same individual always describes the biological circle 

 towards the same side, whence it appears that the individual 

 in travelling along is bound to go to the right or the left. 



\\ ith reference to mankind the ])henomenon may be re- 

 garded as being so well known that one need only mention 

 the familiar accounts in literature and the stories with which 

 people are acquainted in order to make the comprehension of 

 the subject thoroughly real. There are also a multitude of 

 statements as to rowing in a circle in a fog at sea, and in 

 both cases, in wandering as well as in rowing in a circle, the 

 phenomenon has had such a disturbing effect Ujwn the con- 

 dition of the senses, that the individual in some instances did 

 not even trust the compass, and in others, as has been the 

 case with superstitious folk, actually thought himself in the 

 hands of a higher power. Oi this, indeed, there is proof 

 enough in tales and stories from popular life. 



Tlie eflfectd of circular movement also make themselves 



