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Second stage breathing regulator
Second stage breathing regulator

Second stage breathing regulator

Date1953
Object number00031668
NameBreathing regulator
MediumMetal, rubber
DimensionsOverall: 125 x 100 x 250 mm, 1.7 kg
ClassificationsTools and equipment
Credit LineANMM Collection Gift from P Piggot
DescriptionThis second stage breathing regulator is part of a the Porpoise Breathing Appliance Company's underwater breathing apparatus (SCUBA) kit made in Melbourne, Victoria. The set consists of a leather case, first stage breathing regulator and second stage breathing mouth piece with hose. The stage two regulator incorporated a mouth piece with a strap to fit around the head. The black rubber hose was attached to the bottom of the regulator which joins the first stage regulator.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 breathing regulator is associated with the first example of an Australian manufactured modern SCUBA system, of which very few are known to exist. Early models represent the pioneering days of SCUBA diving, and demonstrates the evolving design of diving equipment in Australia and around the world.