( 434 y 
wfiere t was too far ofF ; and from the Mid- way betwixt 
thtm I meafured to the Wall, which Mealure doubled, 
was the Space that the Sound moved in half a Second. 
Here follow the Numbers of Englifl) Feet which a 
Sound moved in one Second of time at leveral Trials. 
I have here added Four o? her Numbers,- Two of them 
Merjenntu mentions, but the firft is that which he relies* 
upon, being the Refult of many Experiments that he 
tried ; he (peaks of it in his Balliji, prop, 39. and elfe- 
where. The Second is grounded upon an Experiment 
which he did not try himfelf, and he queftions whether 
the Obfervation were accurate : He fays, the Sound of a 
great Canon, which was heard in rhe Night \ i" after 
firing, pafled every Second 19x0 French Foot [Tom. 3. 
pa, 163 ] The Third you have in the Book of the Flo- 
Experiments : The Academy del Cmento C2i\kkd 
Six Harquebuffes and Six Chambers to be fired one after 
another at theDiftance of 5739 Englijh Feet, and from 
tiie Flafli to the Arrival of the Report of each was 5'' : 
And repeating the Experiment at the mid-way, the Mo- 
tion was exadly in half the time. 
Feet. 
Feet, 
9. 1291 
10. 1378 
11. I29t 
iz. 1185- 
13. 1178 
Florentine Exper. 3. 1148 
Mr. Boyle'j above 4. l^oo 
f. 1256 
6. 1507 
7. ffitf 
8. 1 1 50 
14. itgo 
If. 1100 
The 
