

NOTES AND QUERIES. 379 



Mr. Butterfield is convinced "from repeated observations that Swallows 

 very rarely exceed 100 miles per hour." An experiment made between 

 Pavia and Milan (Zool. 1886, p. 299) gave the rate of speed at 87| miles 

 per hour. Another experiment, made in Sligo (Zool. 1888, p. 308) with 

 a House Martin, taken from a nest containing young, and liberated at a 

 distance of 10 miles, resulted in the bird reaching the nest in 12 minutes, 

 a rate of speed equivalent to 50 miles per hour. A similar experiment was 

 made with a Swallow, which was taken from the nest near Roubaix and 

 liberated in Paris (Zool. 1889, p. 399). It returned home in an hour and 

 a half, at the rate of two miles a minute, or 120 miles per hour. If these 

 cases are to be relied on, Mr. Butterfield's estimate of 100 miles per hour 

 as the average speed of Swallows is doubtless very near the mark ; for we 

 may assume that a bird having young in the nest, as an incentive to return 

 quickly, would travel at greater speed than on ordinary occasions. Nine 

 persons out of ten accustomed to observe the flight of birds would probably 

 consider the speed of a Swallow to be infinitely greater than that of a Blue- 

 throated Warbler, or — to take an allied species with which they would 

 be more likely to be better acquainted — a Eedstart. What then are we to 

 think of Herr Gatke's estimate above quoted, which places the sustained 

 speed of the Bluethroat when travelling from Egypt to Heligoland at 180 

 miles per hour ? It seems to us incredible, and at all events cannot, we 

 think, be regarded as a definitely ascertained fact. — Ed.] 



The Autumnal Movements of Swallows.— Almost any fine forenoon in 

 September astonishingly large numbers of Swallows may be seen thronging 

 the Sussex coast during their passage eastward. The flights commence 

 generally shortly after sunrise, and continue up to, or even beyond, noon. 

 At first detached parties, more or fewer in number, appear and pass onward ; 

 these being succeeded — but not always immediately — by the more regular 

 stream, which proceeds with an uncertain continuity to the usually somewhat 

 abrupt termination — reminding me indeed, throughout, of a snow-storm. In 

 confirmation of the opening sentence, I may be allowed to transcribe from 

 my note-book some particulars of a migratory flight which took place on the 

 morning of September of last year. A friend and I took up our quarters 

 on the coast a little to the west of St. Leonards, where a projecting bluff 

 enabled us to remark every bird that passed its outermost point, and during 

 four hours (from 8 to 12) I counted the passing birds for one minute each 

 time the minute-hand of my friend's watch reached the successive numbers 

 — i. e. I made twelve counts per hour at intervals of four minutes. The 

 average proved to be 53 per minute, or, roughly, 3000 per hour. This 

 means that 12,000 individuals passed us during the four hours of our stay. 

 It should be borne in mind that this number does not represent the actual 

 passage of birds. Likely enough many thousands passed before our arrival. 

 I think this may be taken as a fair example of what happens more or less 



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