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Sounds move quicker than little ones, \_Ph0ji. fm. 14. ] 
Dr. Plot aKo tells us, the Echo returned the Sound ot a 
Piftol much quicker than a Voice and that it repeated 
more Syllables in the Night than in the Day, [Oxf. pa, 
7.3 whence it follows that the Sound moved flower in 
the Night than in the Day. Kircher fays, that an Echo 
which in the Night repeated Fourteen Syllables, repeat- 
ed but Seven ot them in the Day, IMufurg. li. 9. pa.i^^,'] 
which feems very odd. Becaufe there feems to be 
fo great AflSnity betwixt the Undulation of Water, and 
the Propagation of Sound, therefore the Academy del 
Cimento tried fome Experiments about the firft,- and 
they tell us, that the larger the Stone is which is thrown 
into the Water, and the greater the Force, by fo much 
is the Undulation fwifter : Though Gajjendus had before 
affirmed, that the Undulations of Water are all equally 
fwift. And I have often obferved, that when a Stone 
has been thrown into the Water, the further the Undu- 
lations removed from the Center, the greater was the 
Diftance from one another, even of thofe that rolled the 
fame way : So that the Motion of each precedent Undu- 
lation was quicker than that which followed it. If this 
may be allowed for any Argument, it makes for A7r- 
cher s Opinion. 
By fome of thofe Experiments that I tried, I am incli- 
ned to think, that the Sound moved quicker when it was 
Calm, than in a Wind, even when the Sound moved 
half way with the Wind. Some other Experiments feem'd 
to me to confirm an Opinion oiKircber\ who fays, That 
a Sound moves fwifter at firft than afterward, as is ufual 
in other violent Motions. > 
There is feldom any Echo, where there is not fome 
Wall, Wood, Bank, or fuch like, diredly oppofite, that 
may rcfledt the Soutid to the Perfon that makes it but 
in St> Johns-Grove, if you ftand near the Gate leading 
from 
