In 1911, Hamilton teamed up with Ted Geary, a young yacht designer, to create a number of unique seaplane designs that were seen around Seattle's Lake Washington and various aerial demonstrations of the day. The total number of known aircraft built by Hamilton's Seattle company is estimated to be around 10 to 25 aircraft, though a more accurate account of his aircraft built during the 1909 to 1914 period is yet unknown. His designs were a combination of other designs of the era and his own unique ideas incorporated into the aircraft.
In 1911, Hamilton collaborated with Ted Geary, a young yacht designer, to develop several distinctive seaplane designs that were exhibited around Seattle's Lake Washington and various aerial shows of the time. The total number of known aircraft produced by Hamilton's Seattle firm is estimated to be between 10 and 25, although an exact count for his aircraft built during the 1909 to 1914 period remains uncertain. His designs were a blend of other era designs and his own innovative ideas integrated into the planes.