Mackintosh, like Shackleton, was a former Merchant Navy officer, who had been on the Nimrod expedition until his participation was cut short by an accident that resulted in the loss of his right eye.
Mackintosh, ca Shackleton, era un un fost ofițer al Marinei Comerciale, care a luat parte în Expediția Nimrod, până când a trebuit să fie dat afară din cauza unui accident care i-a provocat pierderea ochiului său drept.