Queensland State Archives posted a photo:
Lytton Fort. The First Shot.
The first shot since the declaration of war was fired from Lytton Fort last evening. Shortly before 10 o’clock a small motor boat was observed gliding across the water in contravention of the regulations providing that no boats shall cruise in the Bay at night. The fort authorities were taking no risks, and immediately one of the guns spoke, and a shot tore across the water in front of the little craft. The occupants of the boat promptly put in to Lytton, and it was ascertained that they were fishermen.
Description source:
The Brisbane Courier, 19 August 1914
View the original record at the Queensland State Archives:
Item ID 2692229