LXXX.] 
OF SELBORNE. 
219 
distance is only 258 yards, or near 75 feet to eacli 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 tliis 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 tlie air thin and 
weak, and deprives it of all its springiness ; and a ruffling wind 
quite defeats the whole. In a still, clear, dewy 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 entertaining, 
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 removed from their bee-gardens, 
he adds 
" — — — — — — aut ubi concava pvilsu 
Siixa sonant, vocisque offensa resultat imago." i 
[There is a natural occurrence to be met with upon the highest 
part of our downs in hot summer days, which always amuses me 
much, without giving me any satisfaction with respect to the 
canse of it; and that is a loud audible humming as of bees in 
the air, though not one insect is to be seen. This sound is to be 
^ " Nor place them where too deep a water flows, 
Or where the yew, their poisonous neighbour, grows ; 
Nor near the steaming stench of muddy ground. 
Nor hollow rocks that remcler hack the sound, 
A nd double images of voice ri boiuid.'' 
(DiiY den's J'irg. Gcorg. \ v. 47-50.) 
