In case this wasn't already posted (sorry if it was, I may have missed it): The Baron Trump books are available in pdf form in the Internet Archives. I've provided links, but feel free to go to the archives to find the pdfs for yourself.
The Adventures of Baron Trump And His Wonderful Dog Bulger.
https://ia600809.us.archive.org/16/items/travelsadventure00lock/travelsadventure00lock.pdf
Baron Trump's Marvelous Underground Journey
https://ia801903.us.archive.org/21/items/barontrumpsmarve00lock/barontrumpsmarve00lock.pdf
1900 or The Last President - All by Ingersoll Lockwood
https://ia801201.us.archive.org/23/items/1900orlastpresid00lock/1900orlastpresid00lock.pdf