Trying to trace my gg-grandfather's first wife. Here's the info I have from the Howe Genealogies:
"John H. Howe...born in Guildhall, VT, 5-1-1830; married Mrs. Alvira Nichols (a widow, ancestry unknown). She died, and he married second, Jane Hagget of Lowell, MA. Children: Sabra Emma, b.abt. 1852; Ithamar, b.abt. 1854; Albion [my great-grandfather, b. Mar 1858]; and Nina [no date].
Albion was married in Pelham, VT in 1882, and Alvira was listed on the back of the marriage certificate as "deceased" and "birthplace unknown." John H. Howe and second wife Jane had a child together in Jan. 1869, meaning that Alvira was dead for at least a year by 1869. I have not found Alvira's death record yet (the family seems to have moved around a lot and I'm not sure where to start looking).

But since she was listed as a widow in the Howe Genealogies, I'm following that lead. Have you gotten any more information on your Alvira? Could we be talking about the same woman? Please reply by email, since I don't check these boards too often. Thanks!