[ 27° j 
compofed in a flat third ; and if the mufic of the 
Turks and Chinefe is examined in Du Halde and 
Dr. Shaw, half of the airs are alfo in a flat third. 
The mufic of two centuries ago is likewife often 
in a flat third, though ninety* nine compofitions out 
of a hundred are now in the lh.trp third. 
The reafon, however, of this alteration feems to 
be very clear: the flat third is plaintive, and confe- 
quently adapted to Ample movements, fuch as may 
be expe&ed in countries where mufic hath not been 
long cultivated. 
There is on the other hand a mod ftriking bril- 
liancy in the fharp third, which is therefore proper 
for the amazing improvements in execution, which 
both fingers and players have arrived at within the 
laft fifty years. 
When Corelli’s mufic was firfl: publifhed, our 
ableft violinifts conceived that it was too difficult to 
be performed ; it is now, however, the firfl com- 
pofition which is attempted by a fcholar. Every year 
alfo now produces greater and greater prodigies upon 
other inftruments, in point of execution. 
I have before obferved, that by attending to a nigh- 
tingale, as well as a robin which was educated under 
him, I always found that the notes reducible to our 
intervals of the o£fave were precifely the fame ; which 
is another proof that birds ling always in the fame key. 
In this circumftance, they differ much from the 
human finger j becaufe thofe who are not able to 
Jing at fight , often begin a fong either above or be- 
low the compafs of their voice, which they are not 
therefore able to go through with. As birds, how- 
ever, form the fame palfages with the fame notes, 
6 at 
