Infantry can take several formations upon the sighting of an opposing close order cavalry formation. Regardiess of the technical name of the formation close order square, open order square, divisional square, battalion mass each of the possible formations entail the packing together of a large quantity of men into a small area, to present as dense a mass as possible.

This tactic is designed to take advantage of a horse's natural instinct to survive, by it's refusal to run into a stationary object. The mounts of a cavalry formation, unlike their more gallant riders, are not willing to do something that is bound to hurt them a great deal; they are not able to rationalize the fact that if a horse runs into a man or several men the men are going to suffer the most.

Horses are not motivated by glory; they are not willing or interested in giving their lives for their country. The evolution of horses, like all animals, correlates injury with death; a horse will always try to veer to the side or stop before contacting a solid object.

Breaking a Square

However, many cases, of which I am aware, of cavalry breaking an unshaken square are the result of a horse being shot and killed immediately in front of the square and the momentum of the horse propelling it into the mass of men, creating a large undefended section of the square's perimeter through which other horsemen can enter the square's vulnerable interior. Therefore, if the men of the square are sufficiently drilled and their morale is high enough to stand their ground in the face of a cavalry charge, a cavalry charge will almost never come into physical contact with a square.

To put it in more modern terms, a heavy cavalry horse and rider could easily weight anywhere from 1400 to 1700 pounds, at least half the weight of a modern car. Most everyone has experienced situations where as a pedestrian, or car passenger, you thought a car was going hit you. Now put yourself in the place of the Napoleonic foot soldier with not one, but hundreds of cars driving at 20 to 30 miles per hour towards you, hubcap to hubcap, and not accidentally, but intentionally trying to run you over; for good measure, since horsemen are armed with swords, carbines, and lances, give the people in the cars baseballs to throw at you, pool cues to thrust at you, and bats to swing at you a rather intimidating situation.

This is an insight to the mind of the Napoleonic foot soldier, your only hope was to stand in Place, remain as close to your mates in the square as you can and hope that everyone else does the same for as soon as order is lost, by failure of morale or a sudden opening in the square's perimeter as a result of enemy firepower, panic ensues. Panic and flight from a threat are contagious "if you're going to run to safety, I'm not going to stand here and die for you."

This defense of presenting a solid continuous front can succeed with a linear formation, instead of a square, however, the length of frontage must be excessive. Typically, linear formations, such as lines, have gaps between each component. Cavalry passing through these gaps can strike the soldiers at the ends of each company and battalion segment. Additionally, the line taken from the end, flanked as it were, presents only three men.

A frontage of three men is completely insufficient to invoke the horse's natural instincts as protection. Each mount slides left or right a couple of feet and the riders can strike each dismounted man in turn as he rides the down length of the formation.

Incoming

A different situation entirely is true when infantry are opposed by artillery. The infantry unit will want to be in as shallow a formation as possible. This is in opposition the needs of the formation when opposed by cavalry (desiring to be as dense and deep as possible). The shallowness of the formation will reduce the number of casualties that are suffered by a formation should a cannonball strike the formation, penetrating only a single file of troops.

It is not unusual in the Napoleonic period for an infantry battalion to lose 25 to 30 percent of its effective force in a single battle due to artillery fire alone, however, a successful cavalry charge can wound, kill, or capture an entire formation or even multiple formations. For the infantry formation, therefore, it is preferable to accept the gradual weakening of a formations manpower by artillery fire than to chance the quick death of a successful cavalry charge. Accordingly, infantry are usually instructed to deploy into square on the first sight of enemy cavalry.

The enigma of dense or thin is the exact aim of the combined arms cavalry assault on infantry. If the infantry find their salvation in forming line, protecting themselves from the artillery, the cavalry may ride them down and will certainly do so if they can gain an advantageous position on the flank of the infantry formation. If the infantry should try to stake their survival on the formation of a square, the artillery can cut them to pieces with round shot through the dense masses of men, or by firing canister at close ranges.

It is recorded that as many as 40 men were killed in a square, by artillery fire, as a single cannon ball passed the length of the square. Most squares being immobile, or virtually so, the infantry cannot chase away the offending enemies, and the firearm carried by infantrymen being of insufficient range they often cannot even trade effective fire with the opposing artillery or cavalry.

Even if the square intended to move, infantry need to be in strict order packed together as tightly as possible to appeal for protecting from the horses natural instincts, and movement or conducting fire can be disorderly to the arraignment of the soldiers, risking the intervention of the very cavalry from which they were intending to safeguard themselves.

Horse Artillery

Horse artillery, having a higher movement rate than foot artillery is the best unit to coordinate with the cavalry in the attack. Cavalry charges, frequently starting as much as a mile from the targeted formation, take about seven minutes to cover 1500 yards. Foot artillery, taking approximately fifteen minutes to cover the same distance, would arrive at the scene of the conflict long after the infantry/cavalry battle was resolved, therefore, the faster pace of horse artillery is required to accompany the cavalry in the attack.

The artillery and cavalry formations must coordinate their approach, to prevent the cavalry formations from physically masking the targets from the accompanying artillery batteries. The cavalry commander must be patient and give the artillery the time necessary to inflict sufficient casualties on the target before he presses the attack, preventing unnecessary casualties to the cavalry and avoiding the possibility of yielding the momentum to the opponent.

The use of the combined arms attack elevates the artillery arm to the primary service. The function of cavalry in this situation is to get the infantry to present the optimum target for the artillery batteries, demoting the cavalry to a secondary or supporting arm for as long as the square remains an intact and functioning entity.

Once the cohesiveness of the square has been disrupted, the cavalry can then regain their ascendancy over the artillery and press the attack, following up with a pursuit of the vanquished foe. Cavalry, regardless of the numerical strength of the opposing mounted forces, can always accomplish great things when properly employed. Combined arms operations against infantry strives to take advantage of the diametrically opposed needs of infantry to be shallow against artillery and deep against cavalry.

Bibliography

Haythornewaite, Philip, Weapons & Equipment of the Napoleonic Wars, Poole, 1979
Jeffries, George, Tactics and Grand Tactics of the Napoleonic Wars, MA, 1982
Jomini, Baron de, Art of War, New York, 1854
Mitchell, H.P., Lieutenant-Colonel J. Thoughts on Tactics and Military Organization, London, 1838