Sky Sweepers 257 



generally discarded. Tt is certain that here and there people 

 will be found who still believe that it is a regular and. com- 

 mon practice. As late as the middle of the eighteenth century 

 men had made affidavits that they had seen swallows revived 

 after winter burial in the mud. Some of the attestants were 

 well known and of good standing. Many of the scientists con- 

 tinued to point out that if fish and mammals hibernated there 

 was no reason to believe that birds did not or could not. 



Most superstitions have vanished, if slowly. We no longer 

 accept the idea that swallows avoid certain places cursed by 

 the gods. Nobody believes that the bodies of swallows are 

 of value for making love potions or for use in auguries. Few 

 could be persuaded that the birds ever went yearly to a 

 sacred island and worked for three days to save it from the 

 floods. Nor do we accept, offhand, Pliny's statement that 

 swallows are never preyed upon by the hawks, for we know 

 that at least two English birds, the hobby and the merlin, 

 do take them. 



As men went into the field, much of the information col- 

 lected was local which could be compared to that which I 

 might gather if this district had been continually isolated 

 from others. If I were fortunate enough to watch the arrival 

 and departure of the seven species of swallows which visited 

 this area, I would not know where they came from or where 

 they were going. I could learn much about the four species 

 which remained to nest: the sites they chose, the date when 

 nesting began, the number of broods raised, the number of 

 young in each brood, the time they left the nest, and their 

 early behavior. I would find that if I blew small feathers 

 from my hand during the nesting season, the barn and tree 

 swallows would swoop down and pick them up before they 

 struck the ground. I would be able to recognize the young 

 birds by their unsteady flight and would often see the old 

 birds feed them on the wing. I might make thousands of such 

 limited observations, but I would have little opportunity to 



