f 5*1 ) 
In this cafe (the vibrations of the equal parts of a 
String being Synchronous) there is no contrariety in their 
motion to hinder each other, whereas it is other wife if 
a Note is unifon to f, in the Fig. D, that does not divide 
the String into equal parts, for then the vibrations of the 
remainder r not futing with thofe of the other parts, 
immediately make a confufion in the whole. 
Nowln the Trumpet-Marine you do not flop clofe as 
in other Inftruments, but touch the String gently with 
your Thumb, whereby there is a mutual concurrence 
of the upper and lower part of the String to produce the 
found. This is fufficiently evident from that, if any 
thing touches the String below the flop, the found will 
be as efFe&ually fpoyled as if it were laid upon that part 
which is immediatly (truck with the Bow, 
From hence therefore we may colled, that the Trum, 
pet-Marine will yield no Mufical found but when the flop 
makes the upper part of the String an aliquot of the 
remainder, and confequently of the whole : otherwife as 
we juft now remark'd of Fig. £>> the vibrations of the 
parts will crofs one another, and make a found fu table 
to their motion, altogether confus ? d. 
Now that thefe aliquot parts are the very flops which 
produce rile Trumpet Notes fliall be plainly fliown in 
treating of the fecond enquiry, viz. What is the reafon 
that the 7th. nth. 13th. and 14th. Notes are out of 
Tune, and the reft exadily in Tune. 
All Writers of the Mathematical part of Mufick agree , 
(half 
That by\a third part 
fliortningA fourth 
a String Oa fifth 
vafixth 
an eighth 
1 |a fifth 
,the found J fourch 
Yftiarp third 
a flat third. 
From 
