Fortunately for innovation, postal service to the backwoods of Pennsylvania was so slow that the letter arrived a day or two after Drake and UncleBilly had, at a depth of 69 and a half feet, struck oil.
The letter was forgotten as, on Aug. 29, 1859, Drake and UncleBilly and his sons got feverishly busy pumping oil and filling wash tubs and whiskey barrels (why we speak of "barrels" of oil today) with the black liquid.