Before the Republic, armies were small and professional. To fight the counter revolutionaries, that were invading from all sides. The French raised vast armies through conscription. With hundreds of thousands of raw recruits, the French adopted new tactics. The trained men were sent ahead (votlages) who would snipe at the enemy. The rest were formed into columns that would drive through the enemy lines. By staying in column marching to the beating drum, even raw recruits would stay together.
Napoleon used this tactic again and again, and was able to beat everyone but Wellington. The British, having learned a thing or two in America, focused on rapid fire with live ammunition. Only the British were able to stop the French columns.
After the Napoleonic wars, large armies that could be raised in week became the norm. The cost of calling out the reserves, was crushing, so if you called out the reserves, it was war. Which was one of the causes of world war 1.
