Historical Aided Diving

Antiquated mechanized diving 

The Diving Bell
The earliest form of aided ocean diving was written about in the 4th century BC: "...they enable the divers to respire equally well by letting down a cauldron, for this does not fill with water, but retains the air, for it is forced straight down into the water."

 The diving bell was one of the oldest forms of travel from the surface of the water to the depths, these were used mainly as a recovery tool when shipwreck recovery attempts were made. Hence the antique block prints which show two rigged ships sending divers to the depths of the ocean floor.

 That's not claustrophobic. I hope they were getting paid good.