126 NATURAL HISTORY OF SELBORNE 



lucky, the identical spot, because the ground rises or falls 

 so immediately, if the speaker either retires or advances, 

 that his mouth would at once be above or below the 

 object. 



We measured this polysyllabical echo with great exact- 

 ness, and found the distance to fall very short of Dr. Plofs 

 rule for distinct articulation ; for the Doctor, in his history 

 of Oxfordshire, allows 120 feet for the return of each syllable 

 distinctly ; hence this echo, which gives ten distinct 

 syllables, ought to measure 400 yards, or 120 feet to each 

 syllable; whereas our distance is only 258 yards, or near 75 

 feet to each syllable. Thus our measure falls short of the 

 Doctor's, as five to eight ; but then it must be acknowledged 

 that this candid philosopher was convinced afterwards, that 

 some latitude must be admitted of in the distance of echoes 

 according to time and place. 



When experiments of this sort are making, it should 

 always be remembered that weather and the time of day 

 have a vast influence on an echo ; for a dull, heavy, moist 

 air deadens and clogs the sound, and hot sunshine renders 

 the air thin and weak, and deprives it of all it's springiness; 

 and a ruffling wind quite defeats the whole. In a still, 

 clear, dew T y evening the air is most elastic ; and perhaps 

 the later the hour the more so. 



Echo has always been so amusing to the imagination, 

 that the poets have personified her ; and in their hands she 

 has been the occasion of many a beautiful fiction. Nor 

 need the gravest man be ashamed to appear taken with 

 such a phenomenon, since it may become the subject of 

 philosophical or mathematical inquiries. 



One should have imagined that echoes, if not entertain- 

 ing, must at least have been harmless and inoffensive ; yet, 

 Virgil advances a strange notion, that they are injurious 

 to bees. After enumerating some probable and reasonable 

 annoyances, such as prudent owners would wish far re- 

 moved from their bee-gardens, he adds 



" aut ubi concava pulsu 



Saxa sonant, vocisque offensa resultat imago." 



