( 3U ) 
• / 
It pen arm’d the firffc 25 Vibrations in 2 
The next 25 Vibrations in 2 
D 
5S 
27 
The fo in 525 
Which gives for each Vibration at a Medium 6 , 5 
The Needle dipp’d 73 0 15' 
EXPERIMENT II. 
Then I fhifted the Needle fo as that Side, which 
before refpe&ed the Eaft, was now turn’d Weft, and 
caufing it to vibrate in the fame Arch, as before, it 
perform’d 
The fir ft 25 Vibrations in 
The next 25 in 
The 50 Vibrations in 
That is, each Vibration in 
The Dip 
73° 5°' 
/ // 
2 49 
2 39 
5 28 
6, 56 
EX P ERIMENT III. 
I now touch’d the fame End of the Needle, a 
fecond Time, on both Sides, upon the fame Stone' 
and fufFering it to vibrate, as before, 
It perform’d 25 Vibrations in 2/ 49" 
That is, one Vibration in 6 , 76 
The Dip 73 ° 
20 ' 
EXPE- 
