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itract S4.

IN GUNNERY, 1791.

133

Whole length of bore, to extremity of the bottom

Diameter of the bore.

Centre of gravity below the axis of motion . .

Centre or axis of the bore below ditto . . .

Weight of the gun alone.

Ditto with all the iron work . -.

174. July 14, 1791.

Barometer 300 ; Thermometer 66.

Began firing the above suspended gun, as follows.

80-5 inc.3'6585-892'21370lb1618

N°

Pow-

der

Vibration of

Point

struck

Plugs

wt

Values of

Velocityof theball

gun

pend

p

g

n

oz

inches

oz

lb

inches

feet

1

32

649

458

84-7

18

1627

7610

40-20

1686

2

630

452

87-4

11

1634

15

22

1620

3

635

465

88-2

10

1641

20

24

1658

4d

24

569

462

91-9

9

1648

25

26

1588

5

549

410

86-2

8

1654

30

28

1508

6

*

549

409

85-9

9

1661

35

30

1517

The guns distance was 30feet; diam. of balls 3'55 inches,wt. Gib lioz. Length of the first charges was 98 inches; ofthe latter 8 - 3.

O zo

My Eprouvette .

Chords Vers. Arc-

42i 9 24*32'

42i 9 24 32

The powder of last years ex-periments gave only between35 and 36 recoil on the chordsof the eprouvette, which an-swers only to 6 on the versed sines: so that the powder ofthis year is considerably stronger than before: yet the men,who had the care of it, asserted that it was the same that re-mained of the former ; but I suspect there is some mistakeon that point, and that it had been removed or changed, andthat they either did not know it, or would not confess it.

The cartridges were now, and hereafter, made of finelawn paper, nicely rounded at the bottom, so as to fit exactlythe bottom of the bore, which is an exact hemisphere; andthe balls were let close into the same paper bags, upon thepowder, with a thread tied round the bag, both below th«