About the effect of canister

ABOUT THE EFFECT OF CANISTER

("Ueber die Wirkung der Kartätschen")

Translated by Geert van Uythoven

Source:

- D.......r: "Ueber die Wirkung der Kartätschen", in ‘Militair-Wochenblatt’ 7. Jahrgang (Berlin 1822) pp.2471-2472, 2477-2478

"Without any doubt, the greater part of the military is of the opinion that the effect of canister is far more fearful and murderous then it really is. With the effect of canister it is the same as with many things in life, which seem fearful at first glance, but which are far from that after careful examination and exposure. If not, how would it be possible for regiments, as has been the case during the battle of Dennewitz and several other affairs, to be thrown back often three times by the heaviest canister fire, only to attack for a fourth time and take the battery by storm?

If we compare the effect of canister with that of roundshot, we always find that the first one is far more uncertain and that, in seemingly comparable circumstances, the results of canister shots can differ greatly from one shot to another. And is this maybe the reason that canister is fearful today, only to have a minor effect tomorrow? By practising, experience, and good and efficient construction of his gun, the artilleryman is indeed able to become master of his roundshot. But he will never become a master of his canister shot.

The effect of canister is influenced by many factors, and only an efficient co-ordination of all of these will give a certain result. Therefore, a careful examination of these factors is preferable. They are:

1. The amount of bullets in a canister round

When from a canister shot every ball would hit; and would every ball have enough kinetic energy [‘Perkussionskraft’] to kill a human being or a horse, or at least be able to inflict a bad wound; undoubtly the best canister would be the one which contains the most balls. Because however, the total weight of a filled canister may not exceed a certain maximum; and the necessary kinetic energy defines the size of every single ball, the amount of bullets which contains a canister can be defined.

When the filled canister round exceeds a certain weight, it will influence the range disadvantageously, as well as the velocity of every single ball; if it is to light, the balls will spread to much. When one maintains the usual powder charge, experience has learned that the weight of 1 ½ roundshot is the most effective weight of a filled canister round. And because of the fact that the amount of balls is inversely proportional to the weight of a single ball, it is necessary to define the weight or size of these. So:

2. Weight of every single ball

The effective range of canister is proportional to the size of its balls. How and in which way this proportion will increase, is still unknown to us. Suppose it will increase with its size proportionally, because of the fact that a 2-löthige ball will have a range 300 paces, a 3-löthige should have a range of only 416 paces; a 6-löthige only 527 paces; a 12-löthige only 663 paces; and a 1-pdr only 948 paces. However, these distances are much to short. Therefore, there must be another factor of a still unknown proportion.

While from the above can be taken that balls with a bigger size will have a proportional greater range as smaller ones, one can note this as a disadvantage for using the latter ones. But this is not the only factor: as canister is used at the shorter ranges, every error in estimating the right distance will be far more sensitive then when using balls with a bigger size. And because of the fact that in such situations one will easily estimate the range to the enemy much closer then it really is, one will often use balls of a smaller size at a range they are not suited for, and gain nothing as a result.

If one would have only canister with balls of a bigger size instead, one would only have to define at which range they will start to be effective. And as a result one would achieve much better results then as it is now, were one has to define many distances, seldom making the right estimation.

As now, such as has been stated, when using balls with a bigger size:

1) have a proportional greater range;

2) estimating distances is simplified, and

3) these have much more kinetic energy,

one cannot doubt anymore that a smaller number of balls with a bigger size has to be preferred above a greater number of smaller balls, and that bigger canister balls have to be preferred above smaller ones in any case.

Regarding the mass of a canister round, it remains to be noted that the greatest weight in the smallest space possible will give the best balls. For this reason one should cast them from lead. Because however this metal is not elastic at all, and that when using canister, ricochet shots will give the best results, one makes them out of wrought iron, a metal which after lead has the best characteristics for this purpose.

3. The way the balls are packed inside the canister, and the position of the sabot

Only when the balls are packed regularly, all have the same size, and every ball is completely round, a summary is possible. Accepting this, the balls can be packed inside the canister in two ways:

1) one ball vertical on the other, so that their diameter is in a straight line, and

2) three balls lying against each other with on them a fourth one, like a pile of roundshot.

When we look at the first possibility, it is clear that not only the first layer of balls on the sabot, but all the following layers of balls will receive an exact central punch. The balls will receive the maximum velocity this way, and their spread will only be minor. Because however this way of packing the balls will never be perfectly possible in reality, but only the second possibility, we will have a look at this more closely. The first layer of balls will also receive a central punch from the sabot, but this will not be the case with the second layer. Instead, every ball in this layer will receive a punch from all three balls beneath it, in three different directions. As will every ball in the next layers. In this way, the parallelogram’s of forces will come into effect; which however will be uneven because of the imperfect position of the balls inside the canister round, as well as the uneven size of the balls. Therefore, every calculation of these forces will fail.

However, the following is clear:

1) the second possibility will cause more spread then the first one, and

2) using the second possibility, the velocity and direction of every ball inside the canister round will be different, and as such not two canister rounds will be exactly the same.

Until now, we have assumed that the position of the sabot is completely parallel to the first layer. But will the punch of it still be central when it will become no exact parallel position when the canister is made and filled with balls? Surely not. And when because of this the first layer of balls will receive no central punch, the next layers will receive it even more less.

Some state that hollow sabot will keep the balls in place much better, but this will still has to be proven yet.

4. Direction and elevation

Although in most cases not much attention is paid to both factors, I still hold the opinion that when firing canister both factors are even more important. A roundshot with too less or too much elevation, could possibly have the effect of a ‘rolling shot’ in the first case. On the contrary, a canister round which is fired with too less or too much elevation, will go completely lost in most instances; as by the least unevenness of the terrain the canister fired with too less elevation will stuck into the ground, while canister fired with too much elevation will go over the heads of the enemy without doing any harm.

Not only the range to the enemy, but also the kind and the state of the terrain define the elevation when using canister. Assuming that, with a certain elevation, when using 2-löthigen balls, an completely level terrain, it is possible to fire effectively at an enemy at a distance of 300 paces, one will hardly be able to do the same with the same elevation on uneven terrain. When one would maintain the same elevation, all balls which will hit the ground before 300 paces will stuck into it, and only a minor part of them will hit the enemy at 300 paces.

The smaller the size of the balls is, the earlier they will stuck into the ground, and the earlier one should fire at a higher elevation. The more elevation however, the bigger the angle of elevation will be, and the more uncertain the shot will be. From this it is clear that:

1) the elevation must be higher on uneven terrain;

2) smaller balls need more elevation, and

3) the probability of a hit is inversely proportional to the amount of elevation.

Also in this case, balls with a smaller size are at a disadvantage compared with balls of a bigger size.

5. Position of the guns

How and in which way one will position a gun in relation to the terrain in front of him, has clearly a great effect on the shot itself. As the angle of incidence can become bigger or smaller this way. The gun would be positioned best when its tube would be aimed straight at the horizon. As this can never be the case in the field, one has to content himself by position the gun itself on level ground. Because of the reason that canister will got stuck into the ground far more easily then roundshot, these will requisite even far more level terrain, especially because of the reason that the greater part of its balls will have only effect when they are able to ricochet. Therefore, it is clear that:

1) the smallest unevenness of the ground will have an important result on the effect of canister, and the terrain needs only to be bit uneven to make canister completely ineffective;

2) because part of the balls will hit the ground close in front of the gun, this ground must be completely level in order for these balls the ricochet, and

3) the guns will have to be placed into an incision [‘eingeschnitten seyn’], or at least being positioned on level terrain.

Because of the reason that condition no. 2 and 3 are contradicting the tactical positioning of artillery, as a result guns can be perfectly positioned to fire roundshot, but badly positioned to fire canister, and the other way round.

Is one able to change position during combat when switching from roundshot to canister or the other way round? Hardly, and even less when in a defensive position. However, as one usually positions guns to fire roundshot instead of canister, it is clear one will chose a position to fire the former. The most important reason that the effect of fired canister is so worse.

6. Formation of the enemy

The effect of canister is diminished by the tactics used during these days. Previously, when the infantry attacked in long thin lines, one had an excellent target for canister, and these seldom failed to reach their goal. Nowadays, when infantry attacks in columns, one can expect a much better effect from roundshot then from canister.

Because of the fact that attacking infantry usually will advance quickly, without firing much; the defending infantry however will be placed in long lines, using their fire to defend, it is clear that canister is much more suitable for attack then for defence.

The cavalry will act by surprise, or in mass attacks. In the former case, the artillery will always come out worse; in the latter case, canister with balls of a bigger size will be more effective them smaller sized ones. When enemy cavalry is standing in position, to be attacked by its own cavalry, canister can be very effective in supporting the attack, when during the attack or even better during the advance of the cavalry the horse artillery manages to unsteady the enemy by firing several quick successive canister rounds into them. In such case, it is preferable to fire as much balls as possible into the enemy in a short period of time. So in this case, balls with a smaller size are to be preferred above balls with a greater size."