Upon reaching the head of Cook Inlet, Bligh was of the opinion that both Knik Arm and Turnagain Arm were the mouths of rivers and not the opening to the Northwest Passage.
Ao chegar ao fondo da enseada de Cook, Bligh era da opinión de que tanto o brazo Knik como o Turnagain eran desembocaduras de ríos e non a apertura do Paso do Noroeste.