IN MEDICINE 141 



year after year for seven consecutive years, 

 at the end of the seventh summer she will 

 leave this precious stone in the nest. A 

 French fable gives still another version. It 

 tells us that the parent swallows search for 

 the stone in the sands of the sea, and when 

 found they take it home and use it to heal 

 the eyes of their nestlings, even restoring the 

 sight when they are blind. It is to this folk 

 tale that Longfellow refers in the opening 

 lines of Evangeline : — 



Oft in the barns they climbed to the populous nests on the 



rafters, 

 Seeking with eager eyes that wondrous stone, which the 



swallow 

 Brings from the shore of the sea to restore the sight of its 



fledglings ; 

 Lucky was he who found that stone in the nest of the 



swallow ! 



How was this magic stone used by man ? 

 For long centuries it was a popular remedy 

 for all manner of eye troubles; and many were 

 the cures, including even blindness, which it 

 was claimed to perform. But more astonish- 



