22 t 
A I R 
pounds; and forty atmofplicres may be injected withfuch 
a fyringe, as well as ten with the larger. 
There are air-guns of various conftruftions; an eafy 
and portable one is reprefented in the annexed Plate, Jig. i. 
which is a fetbion lengthways through the axis, to (hew 
the infide. It is made of brafs, and has two barrels; the 
inner barrel A, of a fmall bore, from which the bullets 
are (hot; and the larger barrel E S C D R, on the outfide 
of it. In the flock of the gun there is a fyringe M N P S, 
whofe rod M, draws out to take in air; and, by puffing 
it in again, the piflon N, drives the air before it, through 
the valve P, into the cavity between the two barrels. 
The ball K, is put down into its placein the fmall barrel, 
with the rammer, as in another gun. There is another 
valve at S L, which, being opened by the trigger O, per¬ 
mits the air to come behind the ball, fo as to drive it out 
with great force. If this valve be opened and (hut fud- 
denly, one charge of condenfed air may make feveral dif- 
cflarges of bullets; becaufe only part of the injefted air 
will then go out at a time, and another bullet may be put 
into the place K : but if the v hole air be difcharged on a 
Angle bullet, it will impel it more forcibly. This dif- 
charge is effefted by means of a lock (Jig. z.) when fixed 
to its place as ufual in other guns ; for, the trigger being 
pulled, the cock will go down and drive a lever which 
opens the valve. 
Dr. Macbride mentions an improvement of the air-gun, 
made by Dr. Ellis; in which the chamber for containing 
the condenfed air is not in the flock, w hich renders the 
machine heavy and unweildy, but has five or fix hollow 
fpheres belonging to it, of about three inches diameter, 
fitted to a fcrew on the lock of the gun. Thefe fpheres 
areVontrived with valves, to confine the air which is forced 
into their cavities, fo that a fervant may carry them ready 
charged with condenfed air : and thus the gun of this 
conflruttion is rendered as light and portable as one of the 
fmallefl fowling-pieces. 
Fig. 3, rep relents an air-gun made by the late Mr. B. 
Martin, of London, and now by feveral of the mathema- 
tical-inftrument and gun makers of the metropolis; which, 
for fimplicity and perfection, perhaps exceeds any other 
that has been contrived- A, is the gun-barrel, of the fize 
and weight of a common fowling-piece, with the lock, 
flock, and ramrod. Under the lock, at B, is a round flee! 
tube, having a fmall moveable pin in the infide, w hich is 
puflied out when the trigger is pulled, by the fpringwork 
within the lock; to this tube B, is fqrewed a hollow cop¬ 
per ball C, perfectly air-tight. This copper ball is fully 
charged with condenfed air by means of a fyringe, previ¬ 
ous to its being applied to the tube B. Hence, if a bullet 
be rammed down in the barrel, the copper ball ferew ed 
fafi, and the trigger be pulled, then the pin in B, will 
forcibly pufh open a valve within the copper ball, and let 
out a portion of the condenfed air; which air will ruth up 
through the aperture of the lock, and forcibly act againfl 
the bullet, driving it to the diftance of fixty or feventy 
yards, or farther. If the air be ftongly condenfed at eve¬ 
ry difeharge, only a portion of the air efcapes from the 
ball; therefore, by re-cocking the piece, another difeharge 
may be made ; and this repeated fifteen or fixteen times. 
An additional barrel is fometimes made, and applied for 
the difeharge of (hot, inftead of the ball above deferibed. 
Sometimes, in a more fimple conftruciion, the fyringe is 
applied to the end of the barrel C, (Jig. 4.) the lock and 
trigger Unit up in a brafs cafe D, and the trigger pulled, 
or the difeharge made, by pulling the chain B. In this 
contrivance there is a round chamber for the condenfed air 
at the end of the fpring at E, and it has a valve acting in 
a fimilar manner to that of the copper ball. When this 
ir.ftrument is not in ufe, the brafs cafe D, is made to Aide 
oft', and the inftrument then becomes a walking-flick: 
from which circumftance, and the barrel being made of 
cane, or brafs, &c. it has been called the air-cane. The 
head of the cane unferew's and takes off at A, where the 
extremity of the pifton-rod in the barrel is (hewn. An 
Vo l. I. No. 14. 
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iron rod is placed in a ring at the end of this, and the air 
is condenfed in the barrel in a manner fimilar to that of 
the gun above; but its force and attion are not near fo 
flrong as in the gun. 
Magazine Aiv.-gws. This is an improvement of the- 
common air-gun, made by that ingenious artift, L. Colbe. 
By his contrivance, ten bullets are fo lodged in a cavity, 
near the place of difeharge, that they may be fucceflively 
drawn into the barrel, and (hot fo quickly as to be nearly 
of the fame ufe as fo many different guns; the only motion- 
required, after the air has been injected, being that of 
(hutting and opening the hammer, and cocking and pull¬ 
ing the trigger. Fig. 5, is a longitudinal fefiion of this 
gun, as large in every part as the gun itfelf; and as much 
of its length is (hewn as is peculiar to this conftruiffion 
the reft of it being like the ordinary air-gun. A B C, is 
part of theflbek; G, is the end of the injecting fyringe, 
with its valve H, opening into the cavity F F F, between 
the barrels. K K K, is the fmall or (hooting barrel, which 
receives the bullets, one at a time, from the magazine D 
E, being a ferpentine cavity, in which the bullets are- 
lodged, and doled at the end D; from whence, by one 
motion of the hammer, they are brought into the barrel 
at I, and thence are (hot out by the opening of the valve 
V, which lets in the condenfed air from the cavity F F F* 
into the channel V K I, and fo along the inner barrel K K, 
whence the bullet is difcharged. L L, is the key of a 
cock, having a hole through it; W'hich hole, in the pre- 
fent (ituation, makes part of the barrel Iv K, being juft of 
the fame bore: fo that the air which is let in at every 
opening of the valve V, comes behind this cock, and, ta¬ 
king the ball out of it, carries it forward, and fo out o£ 4 - 
the mouth of the piece. 
To bring in another bullet to fucceqd I, which is done 
in an inftant, bring the cylindrical cavity of the key of 
the cock, which made part of the barrel K K K, into tfia 
(ituation M N, fo that the part I may be at K ; then turn¬ 
ing the gun upfide-down, one bullet next the cock wfill 
fall into it out of the magazine, but will go no farther in¬ 
to this cylindrical cavity, than the two little pieces ss will 
permit it; by which means only one bullet at a time will 
be taken in to the place I, to be difcharged aghin as be¬ 
fore. 
Air-hole, f. A hole to admit the air. 
AIRINESS, J'. Opennefs; expofure to the air. Light- 
nefs; gaiety; levity.—The French have indeed taken, 
worthy pains to make claflic learning (peak their language; 
if they have not fucceeded, it muft be imputed to a cer¬ 
tain talkativenefs and airinefs reprefented in their tongue, 
which will never agree with the fedatenefs of the Romans, 
or the folemnity of the Greeks. Felton. 
AIRING, f. A (liort journey or ramble to enjoy the 
free air. It is a term peculiarly ufed for the exercifing 
horfes in the open air. It purifies the blood ; purges the 
body from grofs humours; and, as the jockiesexprefs it, 
teaches the horfe how to make his wind rake equally, and 
keep time with the other motions of his body. It alfo 
(harpens the ftomach, and keeps the creature hungry; 
which is a thing of great confequence, as hunters and ra¬ 
cers are very apt to have their flomach fall oft, either from 
want of exercife, or from the too- violent exercife which 
they are often expofed to. Itlikewife greatly contribute* 
to bring a horfe to perfeft wind, and found courage. 
AIR-JACKET,_/! a fort of jacket made of leather, in- 
which are feveral bags, or bladders, compofed of the fame 
materials, communicating with each other. Thefe are 
filled with air through a leather tube, having a brafs flop- 
cock accurately ground at the extremity, by which means 
the air blown in through the tube is confined in the blad¬ 
ders. The jacket muft be wet, before the air be blown 
into the bags, or otherwife it will immediately efcapo 
through the pores of the leather. By the help of thefe 
bladders, which are placed near the bread, the perfon is 
fupported in the water, without making the efforts ufed 
in fwimming. 
3L 
AIRLESS, 
