As he ended up reaching the Arctic Ocean on 14 July, it is conjectured that he named the river "Disappointment River" as it did not lead to Cook Inlet in Alaska as he had expected.
Selv om han nåede helt frem til Nordishavet kaldte han floden Disappointment River («Skuffelsesfloden»), da den ikke førte til Cook Inlet i Alaska som han havde forventet.