Merril says, "I think the details on the tombstone of James, said he was born in Ireland in 1892, but one would need to check this due to the condition of the tombstone, so maybe we need to see if we can find out who he was."

UPDATE from Winnie Solon Bell:
Headstone at St. Bernard's Cemetery in Watertown, WI is very old and difficult to read,
but on 26 Jun 2005, we determined that the following is on the headstone:

In Memory of
JAMES SOLAN
Native of the Co. Mayo
Born Loved
Died
?????????(probably date he died--maybe a 12)
Aged 40 yrs.
& 6 months
May his soul rest in peace
Amen

This is probably the James who came to Dodge County, WI in 1848 with Thomas, Martin and Julia Solon.