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MINUTES OF PROCEEDINGS OF 
the distance of the guns from the object to be hit is never known, hence 
that distance has to be judged by sight or with imperfect instruments; 
thus, there is nothing more probable than an error in such an estimate. 
But it must be observed that the objects to be fired at have always a known 
height, so that if the fall of the projectile is not calculated with perfect 
accuracy, or in other words, if the distance has not been accurately estimated, 
it may happen, that while we aimed at the centre of the object (that 
is, calculating the fall so as to strike the centre of the object) we strike 
either its foot or its upper extremity. Now this is a matter of supreme 
indifference in action. 
Turning then to the supposition we have made, and further supposing 
that we want to strike an object situated at 1090 yards from the muzzle of 
the gun and 6 feet in height: supposing once more that we fire at that 
object with two different guns, having the following fall at the distance 
mentioned:— 
Distances.900 yards.1000 yards.1100 yards. 
Fall of projectile of the 1st gun, . 48 feet. 50 feet. 54 feet. 
n // a 2nd a . 72 n . 77 n . 84 « 
Supposing now that judging the distance at sight, we estimated it at 
900 yards instead of 1000 yards, as it is in fact. 
Tiring from the first gun we aim at a point 48 feet higher than the 
centre of the object to be struck; but as that object is situated not at 900 
but at 1000 yards, the projectile will fall not 48 but 50 feet; the target 
will be struck at 2 feet below its centre. 
Making the same error in the estimation of the distance with the second 
gun, we aim at 72 feet above the object; but as the projectile has fallen 
77 feet, it must pass 5 feet below the centre of the target, that is, at 2 feet 
below its lower edge; hence the object will not be struck. Now, as the 
same error has been supposed to be made in both instances,—the guns 
being supposed to fire with the same degree of accuracy or that one gun 
shoots as well as the other—the two guns give very different results : for 
with the one, despite the error, the target is struck, while with the other 
the object will not be touched. Suppose, then, that the fall of the 
projectile is very small, this will have the effect of making the difference 
of fall at two adjacent distances trifling; and granted that projectiles 
can be made which may be thrown at a high velocity, i.e. with high 
charges: this will be the immense advantage gained by the new guns. 
This reasoning is so true that in the new instructions of the Prussian army 
it is laid down that rifled guns should be fired at long ranges, for at such 
their accuracy of fire makes them advantageous, as the fall of the 
projectile, for reasons which it is unnecessary to enter into here, is less than 
that fired from the smooth bore; while at short ranges the latter species of 
ordnance is to be used, for accuracy of practice at such ranges is of less 
importance as the fall of the projectile is less than that fired by the rifled 
gun. Practice when the fall of the projectile is small is said to give a 
grazing fire. 
A charge of one-third of the weight of the projectile, that is in the same 
ratio as the charges of the smooth-bore guns, introduced with this new gun 
results in uniting the grazing fire of the old artillery (the fire of the new 
