Gettysburg and the ridges to the west of Gettysburg were already occupied by two brigades of cavalry, and those, with a cockiness begotten of big lumps of armed friends approaching from the rear, determined to go on occupying. This, in a spirit of great courage, with slowly increasing forces, against rapidly increasing forces, they did, until the brisk and pliant skirmish which opened the business of the day had grown so in weight and ferocity that it was evident to the least astute that the decisive battle of the New World was being fought.