Frances Dinkelspiel is the author of this wonderful book "Towers of Gold: How One Jewish Immigrant Named Isaias Hellman Created California". Her book, published by St. Martins Press, just recently hit the shelves of bookstores everywhere.
Isaias Hellman is the great great grandfather of Frances. About 8 years ago she wanted to learn more about her family history and started looking at the California Historical Society in San Francisco. There she found literally dozens of boxes full of papers about Hellman.
From her website :
Best news of all for me? Remember the research I posted about my sister-in-law's family? You can find them here, here and here . Well....Isaias Hellman had a daughter Clara. Clara married Emanuel Heller. Emanuel is the brother of SIL's 2nd great grandfather!