A member sent me a link to this eBay auction, now ended, for a Civil War carte-de-visite labeled on the back "A. A. Mitchell / Saddler Sergt. / 2d Me Cavalry / Photographed by / J. S. HENDEE / Rooms, New Block, Water St. / Opposite Stanley House AUGUSTA, ME." I thought I would use this as a case study for tracking Maine people on the Internet. I will do so using only free resources.
The first step is to figure out the soldier's first name. The Civil War Pension Index gives the answer: Albert A. Mitchell was a Saddler Sergeant with the Second Maine Cavalry. A search of the Civil War Soldiers and Sailors System confirms this. A search for "Albert A. Mitchell" in Maine Book Search produces a few good hits in Google Books. Maine in the War for the Union mentions an "Albert A. Mitchell, Canton, Saddler Sergeant" among the field and staff officers of the Maine's Second Cavalry Regiment.
We'll next examine census records. Since Albert served from Canton in the Civil War, there is a good chance he lived nearby in 1860. And indeed, an Albert A. Mitchell, aged 29, lived in Canton, Oxford County, Maine, in 1860. As a "Harness Maker," he would have been well suited to service as a saddler. (To find Albert, I used the free FamilySearch 1860 census index, which links to images at Footnote.com. Using the information gleaned from the index, I was able to find a free image at Internet Archive.)
Albert lived in 1860 with presumed wife Olive F., two children, and a young woman named Susan J. Brown. A search of the FamilySearch Maine Marriages database shows that Albert A. Mitchell married 4 Oct. 1858 in Turner (not far from Canton) Olive F. Brown. This must be the couple shown in the 1860 census. Given the marriage date, the eldest Mitchell child, 5-year-old Frederic, may not have been the biological child of both parents. (Arthur's 1917 obituary confirms that he and Fred were half-brothers.) Notice also that both Albert and Olive would have been older in 1858 than was usual for a first marriage.
We may further speculate that Olive and Susan were sisters, or otherwise closely related. Searching the 1850 census for Susan Browns born about 1836, we find a Susan J. Brown, 14, living in Canton in the family of Russell and Susan Brown. There is no Olive living with the family, but the FamilySearch Maine Births database tells us that Russell and Susan Brown did have a daughter, Olive Fowler Brown, born 12 Mar. 1828 in Pownal. Checking back with the Maine Marriages database, we find that Russell Brown and Susan Tuttle married 29 Dec. 1825 in Pownal.
Returning to Albert, we find him enumerated in Canton in 1850 as "A. A. Mitchell," living in the household of landlord Noah Bosworth and working even then as a harness maker. Peleg and Caroline Mitchell lived nearby, but Hollis Turner's History of Peru does not mention Albert among their children. So who were Albert's parents? We'll revisit that question below.
Let's look for Albert next in the 1870 census. We find him in Canton, now a "Harness Maker & Carriage Trimmer." A third child has been added to the family.
To search the 1880 census, we'll turn to the old FamilySearch site. Here we find that the family has moved to Deering in Cumberland County, and that Albert has become a "Dealer in Agricultural Implements." (We learn from Maine Places that Deering was set off from Westbrook in 1871, incorporated as a city in 1889, and annexed by Portland in 1899.) With a little work, we can turn up a free census image at Internet Archive.
If we look closely at the thumbnail image of Albert's Civil War pension index card at Footnote.com, we can see that the claim was made by his widow in August of 1892. We can presume, then, that Albert died earlier in the year. Since he was notable citizen and native of western Maine, a notice of his death might have appeared in the Lewiston papers. Searching the Google News Archive for [mitchell deering source:Lewiston], and limiting the search to 1892, we find the following in the Lewiston Evening Journal of 1 Apr. 1892:
Albert A. Mitchell, the well known dealer in agricultural supplies in Portland, died at his residence in Deering last Wednesday. Mr. Mitchell was a native of China, Me. He was for several years engaged in business in Canton.
We are very fortunate that Albert was enumerated twice in the 1850 census. As we've seen, he was found by the census taker living in a boarding house in Canton. But Albert A. Mitchell, 19, harness maker, was two days earlier counted in his hometown of China, living in the household of Samuel Mitchell. Living also in that household were an apparent married couple, Jeremiah and Rachael Mitchell.
From their ages, and the order of names, it would appear that Samuel was Albert's grandfather, and that Jeremiah and Rachael were his parents. But Rachael was not Albert's mother, as she married Jeremiah just a year before the census. More likely, Albert's mother was the "Melind" Nelson who married Jeremiah Mitchell 26 Nov. 1829 in China. She died in 1848 and was buried in China Village Cemetery beneath the same stone as Jeremiah.
We have then a tentative genealogical profile of Albert A. Mitchell, son of Jeremiah and Melinda (Nelson) Mitchell, born about 1831 in China; died 30 Mar. 1892 in Deering; married, probably as his second wife, 4 Oct. 1858 in Turner Olive Fowler Brown, daughter of Russell and Susan (Tuttle) Brown, born 12 Mar. 1828 in Pownal. Olive lived as a widow in Portland in 1900 with a son, but probably died before the 1910 census.
Of course, there is much left to do, and not everything can be done online. More and better evidence will be found in town and state records, most of which reside offline. I find in the book Marriage Returns of Oxford County, Maine Prior to 1892 (p. 84) that A. A. Mitchell and Susannah Jones, both of Canton, married in that town 27 Apr. 1851. This was presumably Albert's first wife, and the mother of his eldest son. She, and perhaps others in the family, are perhaps buried in Canton.
Further investigation of Albert's military records would probably tell us approximately when the photograph was taken. His regiment was organized at Augusta between 30 Nov. 1863 and 1 Jan. 1864, and began embarking for the South a week or two later. He appears to be wearing sergeant's insignia on his sleeve.