C 840 ) 
or znO^dve^ or the like) willac the fame time tremble of its 
own accord. The caufe of it , (having been formerly difcuired 
by divers,) f do not now inquire into. Buc add this to the for- 
mer Obfer vat ion ; that, not the whole of that other ftring doth 
thus cremble,buc the feveral parts fcverally , according as they 
are Unifons to the whole, or the parts of that ftring which is fa 
ftruck, Forinftance, fuppofingAC to be an upper Odiave to 
and therefore an Unifon to each half of it, flopped at : 
^ Q 
Now if, while is open, AC be ftruck ; the two halves of this 
other, that is^ee/S and /3>,will both tremble ; but not the middle 
point at /3. Whichwilleafily beobferved, if a little bit of pa- 
per be lightly wrapped about the ftring ny, and removed fuc- 
ceffively from one end of the ftring to the other. In like man- 
ner, if A D be an upper Twelfth to d,J^y and confequently an U- 
A D 
a, r 1 —J" 
/2 y 
mfon to its three parts equally divided in y. Now if, «J^ be- 
ing open, AD be ftruck,its three parts, «^, ^y, yj^ will fcverally 
tremble, but not the poms./,y ^ which may be obferved in like 
auniM^ras the former. In like manner^if AE be a double Oftave 
A E 
iS y <A 
£0 6^ the four quarters of this will tremble, when thaijs 
ftruck, but not the points p.y,^. So if AG be a Fifth to «»; and 
D 
A — — G 
y s 
conrtqiieatly each half of that flopped in D, an Unifon to each 
third parr of thu flopped in • while that 'is ftruck, each part 
of thps m\\ tremble feverally , but not the points ; and 
while is ftruck, each of will tremble , but not the 
point D. The like will hold in lefTer concords; but the left 
remarkably as the number of divifions increafes. 
Th's was fi ft of aIl,C{hat I knowof )difcovered by l/lr^WiHi- 
#w AW^j, a. Mafter of Arts of Mmon-Cdedge '^ and by him 
fiiewed 
