...e mounted guard of the Confederates at a little settlement called Prairie Grove. Divested of his cavalry, he had only about 4,000 effective men. Ignorant of the near presence of a heavy force under Hindman , he left a strong position, drove the Confederate cavalry across the river, and was there confronted by about 20,000 men, well posted on a wooded ridge. Herron did not suspect their number, and, ...