In 1909 Matthew Henson and his Eskimo friends (Today they are called Inuit) went across the Arctic Ocean with Commander Peary. It was very dangerous and very cold. When they found open water blocks of ice were used as rafts to get across. To sleep they built ice shelters called igloos and warmed themselves inside with alcohol burning stoves Matt had made from tin metal. It was 50 and sometimes 60 degrees below zero.  When the wind blew the wind chill made it feel like 100 degrees below zero! Only a man as tough as Commander Peary could have led men through such dangers to reach the North Pole.