On September 20, 1862 Brig. Gen. Oliver O. Howard filed his official report "of the part taken by General Sedgwick's division" in the West Woods on September 17.
At the conclusion of the report, Howard gives the totals for that day's fighting: 355 killed, 1,577 wounded, and 321 missing. Of those wounded between 15 and 20% would die.
What of the missing?
We know that some who were listed as missing eventually returned to their regiments. But many did not. Of these, a certain percentage deserted. "During the war deserters could either remain at large or return to fight again, either willingly or under duress. Roughly a quarter of 'returned' deserters surrendered voluntarily, including those under presidential amnesty proclamation. The rest had been arrested and sent back to the service."
Some deserters returned to their villages and city neighborhoods. If the the community was anti-war, they might be able to settle back into civilian life; if, however, the community was pro-war, they often faced ostracism. This community pressure eventually prompted many deserters to leave the community--often for less populated areas. "After 1863, deserters fled their home communities... [and] were likely to be found in Canada, the Territory of Wyoming, and the mountainous, wooded, and sparsely settled regions of Pennsylvania." .
Others who went missing were captured. Early in the war, most who were captured were paroled or exchanged. Lists of captured soldiers were created by both sides and those on the list were revised from "missing" to "captured."
The likely fate of most of the missing is that they are among the ranks of the unknown who lie buried at the National Cemetery, or in Shepherdstown, Frederick, or Hagerstown.
In honor of Memorial Day, I wanted to see what I could learn more about some of those who went missing in the West Woods.
The 72nd Pennsylvania was an outfit recruited in Philadelphia in the summer of 1861. Also called Baxter's Fire Zouaves, the 72nd was a veteran regiment. On September 17, they stood on the far left of Sedgwick's Division, in Howard's Philadelphia Brigade and as such bore the brunt of the flanking assault by Confederate brigades coming from the south. Casualties in the regiment were high and of those, five soldiers from the 72nd were reported missing. 
William H. Butler, sergeant, Company B.
Charles C. Cooper, private, Company E
John Cornwall, private, Company D
Joseph Henry, private, Company F
John J. McCanna, private, Company D
Theodore Pike, private, Company A
William H. Butler enlisted on October 8, 1861 in Philadelphia. At the time of his enlistment he lived with his family in Philadelphia's center city 13th Ward which was bounded by Poplar Street on the north, Vine on the south, 10th on the west, and 6th on the east. Most of the 72nd were recruited from adjacent wards. The 1860 census lists William's age as 18 and shows that his father was a city alderman and that he was the oldest of eight brothers and one sister. No mother is listed.
The family shows up in the 1870 census (as "Butter"). This time William is not listed but five of his siblings are. William's brother, Lyell, joined the 119th Pennsylvania on August 28, 1862 at age 18 and died in Washington, D.C. on November 18, 1862.  William's other brother, Zachary Taylor Butler is neither listed in the household nor enumerated in the 1870 census.
The 1880 census still has the family living in Philadelphia (his father is now the Secretary of Building Inspectors). Five of William's siblings are still living together but William, Zachary and, of course, Lyell are again not listed.
In the 1900 Pennsylvania census, Zachary Taylor Butler shows up. He is now married, living in Philadelphia and has one son, Lyell, named after his deceased brother.
There is more that needs to be done to find William H. Butler. For now, all that can be said is that he went missing in the West Woods on September 17, 1862.
Next post: Finding Charles C. Cooper.
 Dora L. Costa, Matthew E. Kahn, Heroes & Cowards: The Social Face of War (Princeton University Press, 2008), p. 171.
 Ibid, pp. 170-73.
 Civil War Research Database, retrieved May 1, 2009.
 The Pennsylvania Civil War Project / Pennsylvanians in the Civil War (Penn State University), by Steve Maczuga, Population Research Institute. Retrieved May 21, 2009 at http://cairo.pop.psu.edu/cw/.