BTW, manpower - our false ideas of Union manpower especially - has been a theme here. I was therefore interested in this bit from a letter written by an officer of the Second Maryland USV to Ambrose Burnside after Antietam:
General, at reveille his morning, less than 100 men answered the roll call out of 953 men who reported to you in North Carolina in April, not five months ago.
One regiment does not an army make. And obviously 853 were not killed in one battle, but I hope you find this nugget suggestive.
If you are a conventional historian and the payroll muster is your authority to make statements like "Union forces outnumbered Rebel forces by X to Y," and "McClellan's inexcusable failure to pursue," you need desperately to meditate on the Zen of 1/10th of regimental strength. And Meade's letter to his wife in which he tallies Hooker's present for combat numbers. And the entire Lincoln-McClellan dialog on shirking and wastage. (The least part of it is filed in pop history under "Fleas, barnyard shoveling.")
Fortunately, the Union surgeons compiled and published the numbers from morning roll calls just like these. Forgive me for flogging that dead horse yet again. Surgeon's numbers have been available to reseachers forever - and they paint an irrefutable picture of the baseline of Northern strength figures contrary to muster rolls and what "everyone knows." Some day, even Pulitzer-winning Civil War historians will discover the morning roll call tallies and the eternally awful state of the AOP.