While technical innovations are usually focused upon in war, changes can also develop from other sources. In France, the invention of the divisional system in the eighteenth century, or of the infantry squad in 1917, are very important structural innovations. At the core of this battle group, considering that simple sergeants can be entrusted with tactical responsibilities, is a cultural innovation. There are also many methodological innovations; for example, at the end of 1917, the artillery sought the enemy's neutralization by firing for a few hours (which allowed them to keep the effect of surprise) rather than seeking its total destruction through several days' bombardments. Each of those innovations is, in fact, rarely autonomous. Other incremental technical innovations (rapid fire artillery, gas bombshell, ballistic calculation) preceded the concept of artillery neutralization. The emergence of an innovation in one field sparks off other, secondary changes. When the parachute (technical innovation) appeared, the French claimed that it would promote pilots' cowardice by offering them a way to escape the conflict. It was only in 1916, thanks to the evolution of the equipment, that the French reluctance faded away.