Clay Jenkinson welcomes back David Nicandri for a discussion about Sir Ernest Henry Shackleton, the explorer who led three British expeditions to the Antarctic. They also talk about Thomas Jefferson's influence on exploration. Nicandri is the author of River of Promise: Lewis and Clark on the Columbia and Captain Cook Rediscovered: Voyaging to the Icy Latitudes. Books mentioned on this episode. Subscribe to the Thomas Jefferson Hour on YouTube. Support the show by joining the 1776 Club or by donating to the Thomas Jefferson Hour, Inc. You can learn more about Clay's cultural tours and retreats at jeffersonhour.com/tours. Check out our merch.  You can find Clay's books on our website, along with a list of his favorite books on Jefferson, Lewis and Clark, and other topics. Thomas Jefferson is interpreted by Clay S. Jenkinson.