S4 Bird Life Stories 



then attempt by the powers of mathematics to calculate the 

 length of the various lines it describes. Alas! even his omnipo- 

 tent fluxions would avail him little here, and he would soon 

 abandon the task in despair. 



Yet, that some definite conception may be formed of this 

 extent, let us suppose that this little bird flies in his usual way 

 at the rate of one mile in a minute, which, from the many 

 experiments I have made, I believe to be within the truth, and 

 that he is so engaged for ten hours in every day, and further 

 that this active life is extended to ten years (many of our 

 small birds being known to live much longer even in a state of 

 domestication). The amount of all these, allowing three hun- 

 dred and sixty-five days to a year, would give us two million, 

 one hundred and ninety thousand miles, upward of eighty-seven 

 times the circumference of the globe. 



The Barn-swallow arrives in parts of Pennsylvania from 

 the south on the last week in March or the first week in April, 

 and passes on to the north as far at least as the river St. 

 Lawrence. On the east side of the great range of the Alle- 

 ghany, they are dispersed very generally over the country, 

 wherever there are habitations, even to the summit of high 

 mountains, but on account of the greater coldness of such situ- 

 ations they are usually a week or two later in making their 

 appearance there. On the i6th of May, being on a shooting 

 expedition on the top of Pocono Mountain, Northampton^ 

 where the ice on that and on several successive mornings was 

 more than a quarter of an inch thick, I observed with surprise 

 a pair of these Swallows which had taken up their abode on a 

 miserable cabin there. It was then about sunrise, the ground 

 white with hoar frost, and the male was twittering on the roof 

 by the side of his mate with great sprightliness. The man of 

 the house told me that a single pair came regularly there 



