Self-propelled shark proof cage
Maker
Jim Ellis
Date1975
Object number00004201
NameShark cage
MediumAluminium, nylon
DimensionsOverall: 1060 x 2040 x 1080 mm, 87 kg
ClassificationsTools and equipment
Credit LineANMM Collection
DescriptionThe self-propelled shark proof cage was invented in 1975 by abalone diver James Ellis of Port Lincoln, South Australia.HistoryJames Ellis began construction of the Self Propelled Shark Proof Cage in January 1975 for use in the abalone diving industry as protection against shark attacks. It proved to be successful and the diving cages were quickly embraced by the abalone diving industry. Mounting the motor in rotatable gimbals in the front of the cage made the vehicle highly manoeuvrable. This enabled it to change direction instantly to all points of the compass, both vertically and horizontally. Direction was achieved by pointing the motor where required, and speed by rotating the same ‘joy stick’. Later adaptions included hot water pumped to the diver in the cage and the reduction of the bends because of the reduced physical effort. The original vehicle had a forward mounted rudder with an attached propeller powered by compressed air. Newer vehicles use hydraulic power. The diver inside it can work close to the seabed in complete safety from sharks.
Lincoln Sheet Metal built many diving cages for James Ellis and for the Port Lincoln abalone diving industry. This version was built in mid-late 1975 by Lincoln Sheet Metal for diver Ray Edwards and was acquired by the museum in 1988.
SignificanceThe self-propelled shark cage highlights the dangers and technological innovations in the abalone industry.
