... Army of the Potomac the discharge of 58 regiments had reduced its strength since Chancellorsville by 25,000 effectives, partly replaced by 5 brigades numbering less than 12,000 men. At the battle of Gettysburg the 7 army-corps consisted of 19 infantry divisions, 7 of which had 2 brigades, 11 had 3, and 1 had 4; in all 51 brigades. [See lists of organizations and commanders in The opposing forces in the G...