Many years before 1957, this man became wealthy through prospecting. After gaining his wealth, he took up inventing and poured much money and time into building a "sunlight telegraph", a giant telescope-esque gadget that would reflect concentrated sunlight many miles away from itself and allow for a quick method of message-sending. After the electric telegraph was invented, he realized there was no longer a market for his invention, which he had spent all of his fortune. Now poor and sad, he planned to become a prospector again and even discovered a rich gold vein in Peaceful Valley. However, he was too old and weak to mine it and died sometime before 1957.
He seems to have not had any children of his own. If he did, it can be assumed that they were all deceased by 1957, as his great-great-nephew Hank was his sole heir by then.
Behind the scenes
Hank's great-great-uncle was mentioned in the July of 1957 installment of The Phantom Fires. Though he did not physically appear in the story, his invention, the "sunlight telegraph", and his great-great-nephew, Hank, played a major role in the story.