Possible, the file is tagged 1991. Could be a scan from a 1991 revision of the 1961 book?

While 1991 does seem too recent for the text, 1961 is not possible given it makes several references to later years, up to 1965/1968.

I am curious if this article has been scanned by a machine that attempts to use OCR to improve quality - at the expense of occasional mistakes. "dress" in place of "chess" looks close in font appearance, but far to mistype on a keyboard.

Are you referring to "(so goes an old joke in modern dress)"? I'm pretty certain that is intentional. It's an old joke that has dressed up modern.

I'm pretty sure this first appeared in Gardner's "Mathematical Games" column in the March 1962 issue of Scientific American. Gardner later collected some of his columns and published them in books, which is what you see in this HN submission.

[1] https://www.jstor.org/stable/24937263