23 3 Mr. Thompson’s Experiments 
Fig. 9. reprefents a perpendicular feftion through the line* 
2., 2, fig. 8. and in a line perpendicular to the length of the 
barrel. 
This figure is defigned to {hew the manner in which the 
muzzle of the piece was fupported, and confined in the ring n r 
fig. 8. 
a, 0, are the two ends of the bar that are feen cutoff 
n, is the ring, and 
0, p, are the fcrews bv which it is faflened to the two parallel 
fides of the bar, the ends, of which form the trunnions 2, 2, 
fig. 8. 
d, is a tranfverfe {eflion. of the barrel, and 
r, s, /, are the three fcrews by which, the barrel is fupported: 
and confined in the center of the ring. 
Fig. io» is the fame as fig. 9. but upon a larger fcale.. 
Fig., it. reprefents the two ends of one of the pendulous: 
rods by which the barrel was fufpended ; and fig. 13. {hews the 
fame feen fide ways. 
a, b r is the rod which as feen broken off. 
c\ d, are the pivots by which it was fufpended by a pair of 
hooks or grooves that were fafiened to an horizontal beam, in 
the fame manner as the- pendulum for meafuring the velocities, 
of the: bullets was fufpended. 
e, f, are the hooks which receive the trunnions that are fixed 
to the carriage. ' : 
o 
The dimenfions of every part of this apparatus may he feen 
in the table, p. 242. 
The chord of the arc through which the barrel afcended in 
its recoil was meafured by a ribbon, and the lengths of thofe 
chords, expreffed in inches and decimal parts of an inch, are 
fet .dowri in the tables. The method of computing the vek> 
6 • ■ city 
