A search of copyright renewals was done in publications for the years 1963 and 1964. The search found no information on Railway Age. Therefore there's no evidence that the publication renewed any of its 1936 issues and doesn't continue to claim on this material.
Note that it may still be copyrighted in jurisdictions that do not apply the rule of the shorter term for US works (depending on the date of the author's death), such as Canada (70 years p.m.a.), Mainland China (50 years p.m.a., not Hong Kong or Macao), Germany (70 years p.m.a.), Mexico (100 years p.m.a.), Switzerland (70 years p.m.a.), and other countries with individual treaties.
{{Information |Description=Photo of the New York Central's Mercury. |Source=[https://www.ebay.com/itm/New-York-Central-Railroad-MERCURY-STREAMLINER-DEBUT-1936-article-/370859237826?pt=LH_DefaultDomain_0&hash=item5658eee1c2&nma=true&si=aXb3E7LU1xKbm9DlFa...