Pneu ma tics.

V s let us call », be multiplied by some Num-

'*■ w ‘ll produce a Number of Turns N that shall’■he Rarefaction R in any Receiver proposed. Now

we {hall have n X m —

mX I/. R

L.C

L. 2

whence we have m

1 r °m hence a Table of Multipliers expressing thepo r(; - e of when the Receiver is in any given Pro-Of i larger than the Barrel, is easy to be constructed,aich the following is a Specimen.

Ce ‘*er.

Multiplier-

Capacityof Re-ceiver.

Multiplier.

Capacityof Re-ceiwer*

Multiplier.

1.

20

14,207

300

208,29*1

1,710

3 °

21,139

28,071

400

277,605

2,409

' 40

500

346,920

3,106

59

35,003

600

416,235

3,802

60

4 L 934

709

485,549

4,497

70

48,866

809

554,864

5,191

80

55 , 79 b

900

624,179

5-885

6,579_ 7 , 2.73

9 °

too

200

62,729

69,661

lZb -976

fO.OO

693,494

’’tthi ' means of these two Tables, those who know^lT ar n S of Algebra may find how many Turns are ne rT-gJ to rarify the Air in the Receiver to any giventhat 0 f ’ ^hen the Ratio of the Receiver’s Capacity to^e Ce ; v ^ Barrel, is known. For Example : Let the’hjuj be xo tines as big as the Barrel, and let it behirif v *7 to find how many Turns of the Winch will'►ill j . A* r xoo times. First seek the Number thatM]i C L°T rvhen the Receiver is equal to the Barrel;♦’arts f fiy the first Table is 6 Turns, and 6440 1 oqo of another. Then, against xo in theO 3 second

197