R I F 



ncfs from the breech to the muzzle, than thofe that are 

 intended for fliot only. In every barrel there is an undu- 

 lating vibration communicated to the metal by the explo- 

 fion. This is molt remarkable in a thin barrel, and when 

 the charge is great, and in an equal degree, whether the 

 piece be rifle or plain, and therefore ought to be equally 

 attended to by gunfmiths in both cafes. For more on the 

 fubject of rifle mufket barrels, fee Robins' Tracts, vol. i. 

 p. 328, &c. ; fee alfo Nicholfon's Philofophical Journal, 

 vol. i. p. 3H2 ; and for rifle ordnance, fee the Memoir 

 of the National Inltitutc mentioned in the following ar- 

 ticle. 



Rifle Ordnance. After the important advantages at- 

 tending rifled barrel mufkets were well underftood, the 

 idea naturally occurred of carrying the fame improvements 

 into cannons and field-pieces, and many experiments have 

 been made with a view of conltructing thefe on fimilar 

 principles to the mufket. The firft attempt of this kind 

 was made by Dr. Lind, and Capt. Alexander Blair, of the 

 69th regiment, in 1774. The pieces are of call iron, and 

 are not bored like the common cannon, but have the rifles 

 moulded on their core, after which they are cleaned out, and 

 furnifhed with the proper initruments. 



Guns of this dclcription, which are intended for the field, 

 ought never to be made to carry a ball of above one or two 

 pounds weight at molt ; a leaden bullet of that weight being 

 fufficient to deitroy either man or horfe. A pound gun of 

 this defcription, of good metal, need not weigh above an 

 hundred weight, and its carriage about another hund-.ed, 

 and may therefore be eafily tranfported from place to place 

 by a few men, and a couple of good horfes may tranfport 

 fix of thefe guns and their carriages, if put into a cart. 

 But for other purpofes, in which a greater momentum is 

 neceffary, there is nothing to prevent them being made of the 

 ufual calibre. 



The following are the dimenfions that have been recom- 

 mended for thele kinds ol cannon. The length of the gun 

 being divided into'feven equal parts, the length of the firft 

 reinforce is two of thefe parts ; the fecond reinforce I-j-£ 

 of the diameter of the calibre ; the chafe 3-^ diameter of 

 the calibre. The diftance of the hind part of the bafe ring 

 to the beginning of the bore is l T V calibre. The trunnions 

 are each one calibre in length, and the fame in breadth ; their 

 centres are placed -fths of the length of the gun from the 

 hind part of the bafe ring, in fuch a manner, that the axis 

 of the trunnions pafs through the centre line of the bore, 

 which prevents the gun from kicking, and breaking its car- 

 riage. The length of the eafcable is 144 °f a calibre. 



The calibre of the gun being divided into 16 equal parts ; 

 then 



The thicknefs of metal from the bafe ring to the 1 n 

 bore, is- - - - - J J 



At the end of the firft reinforce - - 17 



At the fame place for the beginning of the fecond 1 

 reinforce - - - - j ' 



At the end of the fecond reinforce 15 



At the fame place for the beginning of the chafe '3-75 



At the end of the chafe, or muzzle, the mouldings 1 

 excluded - - - - ■J 



At the fwelling of the muzzle 



At the muzzle fillet ... 



At the extreme moulding ... 



Bafe ring ..... 



Ogee next the bafe ring ... 



The aftragal, or half round - 



Its fillet ..... 



12 



9-5 



8 



5-5 

 5-5 



4-75 

 1 



R 1 F 



Total aftragal and fillets at the vent-field - 4. 



Firft reinforce ring .... .r 



Second reinforce ring ... , » 



Its ogee ..... j 

 Its aftragal ----- i.r 



And its fillet .... 1 



The muzzle, aftragal and fillet a 



Breadth of the fillet at the bafe ring - 1 



Diftance of the fillet at the button from the fillet at 1 

 the bafe ring - - - - 3 



Breadth of the fillet at the button - - 1 



Diameter of the fillet at the button - . 18 



Diftance of the centre of the button from its fillet \z 



Diameter of the button - - - 18 



Diameter of its neck ... 10. c 



The vent Ihould be placed about half an inch from the 

 bottom of the chamber or bore, that the cartridge may be 

 pricked, left fome of the bottom of the cartridges fhould be 

 left when the gun is fponged, which might retard the firing 

 till the ball be again drawn, which is very difficult in pieces 

 of this kind. 



The rifles in this gun make one fpiral turn in the length of 

 the bore, but go no nearer to the breech, in their full fize, 

 than two calibres, and terminate in a gentle flope in half a 

 calibre more, fo as not to prevent the cartridge, with the 

 powder, from being eafily fent home to the bottom of the 

 gun, which would otherwife coullantly happen with the 

 flannel cartridges, and even fometimes with paper ones, if 

 not made to enter very loofely. The fhape of the rifles is 

 iemicircular, their breadth being equal to the diameter, 

 which is -tths of the calibre, and their depth . c ths of a ca- 

 libre. The bullets are of lead, having iix knobs calt on 

 them, to fit the rifles of the gun ; and being thus made of 

 foft metal, they do not injure the rifles. 



Rifle ordnance, however, of any calibre, might be made to 

 carry iron fhot for battering, or for other purpofes ; pro- 

 vided holes, that are a little wider at their bottoms than at 

 their upper parts, be calt in a zone round the ball, for re- 

 ceiving afterwards leaden knobs to fit the rifles of the can- 

 non ; by which means the iron fhot will have its intended line 

 of direction preferved, without injuring the rifles more than 

 if the whole ball was of lead, the rotatory motion rouisd its 

 axis, or the line of its direction, which corrects the aberra- 

 tion, being communicated to it by the leaden knobs follow- 

 ing the fpiral turn of the rifles in their progrefs out of the 

 gun. It is particularly to be obferved, that the balls mult 

 be made to go eafily down into the piece, fo that the car- 

 tridge with the powder, and the bullet, may be both fent. 

 home together withafingle pufh of the hand, without any 

 wadding above either the powder or the ball, by which 

 means the gun is quickly loaded, and the ball flies farther 

 than when it is forcibly driven into the gun, as was found 

 from many experiments. The only reafon why, in common 

 rifle mufkets, the bullets are forcibly rammed in, is, that 

 the zone of the ball which is contiguous to the infide of the 

 bore, may have the figure of the rifles imprefled upon it, in 

 fuch a manner, as to become part of a male fere w, exactly- 

 fitting the indents of the rifle, which is not at all neceflary 

 in the prefent cale, the figure of the rifles being, in the 

 firft initance, calt upon the ball. Thefe knobs retard the 

 flight of the ball in fome degree, but this fmall difadvantage 

 is fully counterbalanced by the eafe with winch the gun is 

 loaded, its fervice being nearly as quick as that of a com- 

 mon field-piece, and the retardation and quantity of the 

 whirling motion which is communicated to the bullet being 

 conftantly the fame, it will not in the lealt affeft the experi- 

 ments 



