Part of the Library of Congress' Chronicling America project. Full-text search across well over a hundred newspapers from around the country, and you can search by state and date range. A lot of this is pre-1923 which also makes a lot of this public domain.
Go to the LoC newspaper search page
I searched for "mermaid" (of course) and found the "Mermaids of the Cliff House Beach" from The San Francisco Call, November 06, 1910, Page 16--including the mermaid on the right typing at a typewriter.
Click the image or the link below for the full page: