Saphroneth
Lt. Colonel
- Joined
- Feb 18, 2017
An idea sparked from noticing something about Vicksburg.
There is an inspection report of the Vicksburg garrison just after the siege started, which shows only ca. 17,000 muskets and rifles defending the place. This means that the upper bound for the number of troops which could be used to defend Vicksburg at any one time is about 17,000 (effective infantry).
Grant, after the battle of Big Black River, had about 46,000 PFD with his army when he reached Vicksburg proper, and got over 25,000 (PFD) reinforcements during the siege. He was never able to break in successfully and ultimately took Vicksburg by siege.
The 30 April 1862 reports on strength at the Yorktown position in Virginia give effective strength by regiment, and adding up the regiments present on the 5th-6th of April (when McClellan contacted the line) gives:
(Infantry effectives only)
5th:
McLaws 1,977
Cobb (some of which arrived on the 6th) 3,748
Colston 1,750
Wilcox 2,552
Pryor 2,250
Ward 890
Rains 1,830
6th
Rodes 2,960
(most of) Early 2,300
Rest of Cobb
For about 20,250 infantry effectives in position on the 6th of April, not counting Gloucester Point or the (significant) artillery. This number also assumes no sickness took place over the whole month of April, when contemporary reports suggest the 30 April figures were after 10%-20% of the army took sick in the trenches.
(Note that on the 7th Kershaw's brigade arrives with another 2,490 infantry effectives, and on the 9th Featherston and Griffith's brigades arrive with a total of over 4,600 further infantry effectives. So within days it's more like 27,000 infantry effectives.)
McClellan's PFD when making contact with Yorktown is five divisions and one brigade. We don't have exact returns for them, but even with the much larger size of Federal divisions in 1862 it seems unlikely there'd be more than 60,000 PFD involved.
So, here's the point I was leading up to...
What about Vicksburg makes it so that Grant can't break in in two months with more than three times the PFD that his opponent has effectives, when McClellan is criticized at Yorktown for not taking it in much less than a month with less of an advantage?
There is an inspection report of the Vicksburg garrison just after the siege started, which shows only ca. 17,000 muskets and rifles defending the place. This means that the upper bound for the number of troops which could be used to defend Vicksburg at any one time is about 17,000 (effective infantry).
Grant, after the battle of Big Black River, had about 46,000 PFD with his army when he reached Vicksburg proper, and got over 25,000 (PFD) reinforcements during the siege. He was never able to break in successfully and ultimately took Vicksburg by siege.
The 30 April 1862 reports on strength at the Yorktown position in Virginia give effective strength by regiment, and adding up the regiments present on the 5th-6th of April (when McClellan contacted the line) gives:
(Infantry effectives only)
5th:
McLaws 1,977
Cobb (some of which arrived on the 6th) 3,748
Colston 1,750
Wilcox 2,552
Pryor 2,250
Ward 890
Rains 1,830
6th
Rodes 2,960
(most of) Early 2,300
Rest of Cobb
For about 20,250 infantry effectives in position on the 6th of April, not counting Gloucester Point or the (significant) artillery. This number also assumes no sickness took place over the whole month of April, when contemporary reports suggest the 30 April figures were after 10%-20% of the army took sick in the trenches.
(Note that on the 7th Kershaw's brigade arrives with another 2,490 infantry effectives, and on the 9th Featherston and Griffith's brigades arrive with a total of over 4,600 further infantry effectives. So within days it's more like 27,000 infantry effectives.)
McClellan's PFD when making contact with Yorktown is five divisions and one brigade. We don't have exact returns for them, but even with the much larger size of Federal divisions in 1862 it seems unlikely there'd be more than 60,000 PFD involved.
So, here's the point I was leading up to...
What about Vicksburg makes it so that Grant can't break in in two months with more than three times the PFD that his opponent has effectives, when McClellan is criticized at Yorktown for not taking it in much less than a month with less of an advantage?