National Geographic : 1952 Mar
+ A Great Lakes Carrier Hauls 14,000 Tons of Iron Ore Down St. Marys River to Speed the Nation's Remobilization Back and forth along this life line of liberty steam approximately 300 ore ships moving 70-80 million tons a year. This 600-foot vessel canload inthree-and-a-half hours and discharge in six. Below: Lake of the Clouds is a jewel of the Upper Peninsula'sPorcupine Mountains. © National Geographic Society 313 Kodachrome byAndrew H.Brown . . 4.