Twin tank set with cloth harness

Datec 1950

Object number00031670

NameAir tank

MediumSteel, cotton

DimensionsOverall: 560 x 340 x 195 mm

ClassificationsTools and equipment

Credit LineANMM Collection Gift from P Piggot

Terms

DescriptionThis twin air tank with a cloth harness allowed divers to breathe underwater. The tanks are equipped with two pillar valves and a joining manifold and one is stamped with the mark of the US government. Joining two individual air tanks together like this allowed the user to double the amount of time underwater. This tank was used between 1953 and 1958 for diving in NSW, Queensland and the Great Barrier Reef.HistoryIn 1837 the first diving suit as we know it today was made by Augustus Siebe. It consisted of a waterproof suit and airtight helmet. The diver was supplied with air from a hose attached to a surface air pump. The system was problematic because divers could not regulate their air flow and were only permitted small quantities of air. The development of the high pressure compressor in the 1900s and the Ohgushi Peerless Respirator in 1918, allowed divers to manually adjust their air flow with a valve. During the 1940s Jacques Cousteau, Emile Gagnan and M Melchoir working for the French company L'Air Liquide developed a twin hose diving regulator known as the aqualung, that allowed divers to breathe underwater. The company took out worldwide patents to protect their revolutionary development. In an effort to get around the French patents the Melbourne based engineer Ted Eldred separated the components of the aqualung into a first and second stage regulator linked by a single rubber hose. To manufacture his single hose regulator Eldred founded a company called the Breathing Appliance Company and began selling Porpoise Breathing Sets in Australia. The Porpoise Kit was first sold in Australia in 1953. It was made up of a second stage regulator with a mouth piece and strap to fit around the wearer's head. A black rubber hose then attached to the bottom of this regulator and the stage one regulator. The air tank was linked to the stage two regulators via two separate screw-on sections. The system featured a silver hexagonal valve to regulate the diver's air flow.SignificanceThis air tank reflects technological advancements in diving equipment during the 20th century. The development of underwater breathing equipment has been integral to commercial, recreational and professional diving in Australia.