...nd 80,000 would be required for the march, of which 20,000 could act as a rear guard in Maryland, to hold off the Yankee reinforcements, while 60,000 investigated once more the bravery of the gallant Bull Run ners. To the unthinking mind, nothing would seem more simple than the forward movement of our army. But it has to be fed, and baggage trains have to be provided, and a thousand other things, invol...