It has been a long time. Very few discoveries have been made during that time. But it seems that the moment I came back to my research, I was rewarded with results.
1. James Marryatt, my international man of mystery, became a naturalized U.S. citizen in late August 1873. Days later, at the start of September, he registered to vote in San Francisco. Another book, detailing the life of his one-time employer, Charles King, told of Marryatt accompanying King to New Haven, Ct., also in the early 1870s. He married Adaline Hawkins at about that time as well.
2. My great-grandmother, Narciss Hughes DeLeon, has parents: Lizzie and Woodford Hughes. And grandparents: Caroline and Isham (Isam?) Hughs, the latter born in 1799 — my first 18th-century ancestor.
Thus I have new leads to pursue, along with the colder trails.