David Lawson wrote the following concerning Charles A. Buck's booklet, Paul Morphy: His Later Life
(Paul Morphy: the Pride and Sorrow of Chess - page 213)

Charles A. Buck, Author of a little pamphlet on Morphy, Paul Morphy, His Later Life , written some seventy-five years ago, appears to be responsible for a number of erroneous statements that have been widely accepted.

Then gave this background information (pp. 214-215)

Buck first published Paul Morphy in the Evening Gazette of Cedar Rapids, Iowa, on December 29, 1900, and it was later reprinted in the American Chess World of January 1901. Will H. Lyons published it in the pamphlet form in January 19902 and added His Later Life to the title. Evidently, Buck did not consult Morphy’s Chess Monthly, the Ledger, or other major sources, for the pamphlet contains numerous errors in addition to that already cited. He apparently just talked to “old-timers” and did little research for his article.

along with this cautionary enumeration

The Following corrections to false statements in Buck’s pamphlet should be especially noted:
-Stanley did not win one of his match games with Morphy at the odds of Pawn and move.
-Morphy annotated thirty-five Labourdonnais-M’Donnell games, not fifteen as Buck states.
-Morphy did complete his contract with the Ledger, although Fuller helped.
-Fiske, in a letter to Will Lyons dated February 5, 1901, says Buck “errs when he states that Mr. Morphy contributed very little to the Chess Monthly.”
-There is no evidence that Morphy was rejected by anyone because he was “a mere chess player,” even though Frances Parkinson Keyes corroborates Buck in this contention. Keyes’s novel about Morphy is more fiction than fact.
-Morphy returned to New Orleans in 1864, not 1865 as Buck states.
-He did play some chess after 1869.
-Zukertort did not meet Morphy in 1882 as Buck states he did, nor is it likely that they ever met. Zukertort first visited New Orleans in 1884.
-Buck mentions an incident concerning a lawyer, a piece of candy, and a remark that he says Morphy made, about all of which nothing whatsoever can be authenticated. It is like to have as much substance as other statements by Buck called into question here.
-The New York Chess Club never acquired Morphy’s chessmen as Buck states it did.
The “apochryphal”: game was played between Löwenthal and a Mr. Murphy of London in 1855.
-Morphy was co-editor of the Chess Monthly for three years, not five.
-It is not difficult to determine the first symptoms of his malady. Rumors of a Morphy mental condition started in 1875, not 1871 as Buck states. Maurian says he first noticed something was wrong with Morphy in 1875.
-Morphy was taken to the Louisiana Retreat in 1875, not in 1882.
-Colonel Mead in his address of welcome at the testimonial reception did not refer to chess as a profession. Morphy did not resent anything he says. Mead did not retire in confusion and mortification, but remained as chairman throughout the proceedings as previously stated.