However this presently appeared. Gustavus Adolphus was the first who tried to introduce method and coördination into infantry fire. Others, eager for innovations, followed in his path. There appeared successively, fire by rank, in two ranks, by subdivision, section, platoon, company, battalion, file fire, parapet fire, a formal fire at will, and so many others that we can be sure that all combinations were tried at this time.
Fire by ranks was undoubtedly the first of these; it will give us a line on the others.
Infantry was formed six deep. To execute fire by rank all ranks except the last knelt. The last rank fired and reloaded. The rank in front of it then rose and did the same thing, as did all other ranks successively. The whole operation was then recommenced.
Thus the first group firing was executed successively by ranks.
Montecuculli said, "The musketeers are ranged six deep, so that the last rank has reloaded by the time the first has fired, and takes up the fire again, so that the enemy has to face continuous fire."
However, under Condé and Turenne, we see the French army use only fire at will.
It is true that at this time fire was regarded only as an accessory. The infantry of the line which, since the exploit of the Flemish, the Swiss and the Spaniards, had seen their influence grow daily, was required for the charge and the advance and consequently was armed with pikes.
In the most celebrated battles of these times, Rocroi, Nordlingen, Lens, Rethel and the Dunes, we see the infantry work in this way. The two armies, in straight lines, commenced by bombarding each other, charged with their cavalry wings, and advanced with their infantry in the center. The bravest or best disciplined infantry drove back the other, and often, if one of its wings was victorious, finished by routing it. No marked influence of fire is found at this time. The tradition of Pescani was lost.
Nevertheless fire-arms improved; they became more effective and tended to replace the pike. The use of the pike obliged the soldier to remain in ranks, to fight only in certain cases, and exposed him to injury without being able to return blow for blow. And, this is exceedingly instructive, the soldier had by this time an instinctive dislike of this arm, which often condemned him to a passive role. This dislike necessitated giving high pay and privilege to obtain pikemen. And in spite of all at the first chance the soldier threw away his pike for a musket.
The pikes themselves gradually disappeared before firearms; the ranks thinned to permit the use of the latter. Four rank formation was used, and fire tried in that order, by rank, by two ranks, upright, kneeling, etc.