Sir Alexander Mackenzie is known to schoolchildren as a great Canadian explorer who gave his name to the country's longest river, but hardly anyone could name the man who mentored Mackenzie and mapped much of northwestern Canada before him. Soldier, fur trader and explorer Peter Pond, the subject of this long overdue book, is a man whose legend has been forgotten in favor of those who came after him. Much of Pond's life is shadowed in mystery. Historian...