INTRODUCTION: Demand regulator/tank scuba unit
USE CASE: Breathing underwater
PRIOR SOLUTION: [-]Surface supplied air[/-]
Yves le Prieur manually operated open circuit SCUBA. Credited by Cousteau as the ancestor to the Aqualung in his book,
The Silent World
INTRODUCTION: Wetsuit
USE CASE: Exposure protection
PRIOR SOLUTION: [-]none[/-] Drysuits without waterproof zippers. The Cousteau Constant Volume Suit and Aquala vulcanized drysuits were available in the late 1940s and were used in cold water by the early pioneers. See:
From the archives: Back in the 50s ? Nitrox and Rebreathers, so what?s new? | DIVER magazine
INTRODUCTION: SPG
USE CASE: Determining gas supply
PRIOR SOLUTION: J-valve Edit: or just wait until it got hard to breathe. The majority of valves sold were non-reserve K-valves. You could get away with it because regulators breathed much harder at low supply pressures and gave you plenty of warning
and ascent rates were 60'/minute.
INTRODUCTION: Broad commercial agencies with reach through shops/resort
USE CASE: Training and certification
PRIOR SOLUTION: Clubs and universities EDIT: and dive shops that developed their own curriculum. That was still true when I got my first card in 1962 in the Bay Area.
INTRODUCTION[/B]: Octo/alt reg
USE CASE: Primary failure or otherwise not available
PRIOR SOLUTION: [-]None[/-] Buddy Breathing and free ascents
INTRODUCTION: Low pressure power inflator
USE CASE: BCD inflation
PRIOR SOLUTION: Mouthpiece [-]only[/-] and tiny dedicated HP bottle mounted on the horse collar, see Bouée Fenzy. Surface inflation on Mae Wests were oral and CO
2 cartridges before that, which could not be orally inflated at depth because there was no OPV (Over Pressure Valve)
