TROUT RS) Bis VE) WE: 185. 
of a diameter fufficient for the worm to extend its full 
length, as far as I could difcover. The humours of the 
eye were beginning to grow opake like a chilled jelly, and 
became altogether fo afterwards, as I was informed. 
As this is a very uncommon circumftance and may af- 
fe& fome philofophical doctrines, it is much to be lament- 
ed that the horfe had not been purchafed, and the eye 
diffected for better examination. ‘That there was a living, 
felf-moving worm within the ball of the horfe’s eye, free 
from all deception or miftake, Iam moft confident. How 
this worm got there, or if bred in fo remarkable a place, 
where its parents came from, or how they contrived to 
depofite their femen or convey their egg into the eye of 
an horfe, I leave for others to determine. 
N° XIX. 
An improved Method of Quilling a Harpfichord, by 
F. Hopkinson, £/quire. 
Read Dec. UCH of the pleafure and effec in perform- 
a: ing on a harpfichord depends on the equa- 
lity of what is called the touch ; and this is principally 
owing to a continuance of uniformity in the fpring of the 
little quills, which by their impulfe fet the ftrings in vi- 
bration. ‘Thefe quills, in the prefent manner of applying 
them, will not retain their elafticity for any length of 
time, but require conftant repair; which is one of the moft 
troublefome and difficult operations in keeping the inftru-- 
ment in order. To remedy this inconvenience, I have 
fought for a fubftitute for the crow quill, and tried a va- 
riety of fubftances, but without fuccefs.. I then confider- 
ed whether an improvement might not be made in the 
application of the quills themfelves, and to this purpofe I 
examined: 
