Twenty-seven years later, upon a request from Tacitus, Pliny the Younger provided an account (obtained from the survivors from Stabiae) of his uncle's death. Suetonius wrote that Pliny approached the shore only from scientific interest and then asked a slave to kill him to avoid heat from the volcano. Jacob Bigelow, after summarizing the information about Pliny's death contained in Pliny the Younger's letter to Tacitus, concluded that Pliny had died from apoplexy or heart disease. In 1967, science historian Conway Zirkle similarly stated that "there is widespread and persisting misinformation" about Pliny's death. He suggested that despite his rescue attempt, Pliny never came within miles of Mount Vesuvius and no evidence has been found that shows he died from breathing in fumes, and like Bigelow, concluded that he died of a heart attack.