Profit in silk and spices lured them into Arctic straits, but the chilling reality of the Little Ice Age blocked their passage. And so Henry Hudson and his mutinous crew turned westward armed with vague charts and supposed sightings of the Indian Ocean across a narrow sandy isthmus. Upon their arrival, crowds of curious Manhattans greeted them in canoes made from tree trunks. Dressed in animal skins and mantles woven of turkey feathers, they offered...