LOCKS. 173 



The former is always adopted with shot-guns and sporting 

 rifles, while the latter is generally applied to military 

 arms. Thus a gun of 12 gauge carries a ball weighing 

 the twelfth part of a pound avoirdupois ; a 14 gauge 

 carries one of fourteen to the pound, and so on. For 

 sporting purposes, shot-guns are now generally made of 12 

 or 14 bore : but where great lightness is required, 16 or 18 

 even may be adopted. These gauges measure severally in 

 inches or parts of an inch, as shown in the opposite table : 

 It is therefore easy for any one knowing the gauge of his 

 gun or rifle to get an approximate idea of its diameter in 

 inches; and on the other hand, if the diameter is known in. 

 inches, a sufficiently accurate guess for practical purposes 

 may be made at its gauge, or in other words, at the weight 

 of the spJierical ball which it will carry. The diameter of 

 the intermediate gauges is not exactly in proportion to 

 those above and below, as the scale between 4 and 16 

 does not descend in a straight line, but in a slightly concave 

 one. Without actual measurement, therefore, the precise 

 diameter in decimal parts of an inch cannot be given, but 

 for practical purposes the fractional parts here introduced 

 are sufficient. 



LOCKS. 



The first spring locks for the use of the flint-gun were made 

 in the beginning of the sixteenth century, but they were rude 

 in the extreme, and though they effected the discharge of 

 the gun, they took their time to do it. Previously to this, 

 the powder was exploded by a match, which would forbid the 

 use of the barrel except towards sitting objects. The spring 

 flint-lock was therefore a considerable step, and by the aid of 

 various clever inventors, it was brought to great perfection. 

 Indeed, so useful and deadly was the flint-gun in the time of 

 the Mantons, that they were long before they could be in- 

 duced to adopt the next invention, to which we are now 

 indebted for the quick shooting which all our modern kinds 

 give. This was the discovery of the mode of firing gunpowder 

 by exploding close to it a small quantity of a composition 

 -which would take fire on being sharply struck with a hard 

 body. From this circumstance the plan was called the per- 



