Mail began to be carried on the Lake in the late 1800’s, but the first official date was 1892 when Rural Free Delivery Route #7 was set up under contract to Dr. George Saltmarsh with the vessel Robert and Arthur the first mailboat. In 1896 the Dolphin replaced it in service, and in 1906 the mail contract put the newly launched Uncle Sam onto the run as the third mailboat. In 1916, by Act of Congress (the only such incident in the United States to date), the Uncle Sam became the only floating-post office. For the years 1932 & 3 the Marshall Foch took the honors, but it was displaced in ’34 by the Uncle Sam I, which ran uninterrupted until destroyed due to old age after the end of the 1961 season. 1962 saw a new Uncle Sam II, a 72 foot converted PT-Boat, brought in by rail and launched for the increased traffic from many countries.
My dad was stationed at the naval supply station in Newfoundland during WWII. When the mailboat goes by, he mentioned it was a 'Higgins'.
https://www.lakewinnipesaukee.net/boating/mail-boats/