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There are explanations of gear choices such as gauges and tanks, and compressors and regulators, and sections on earth sciences and diving.

Some sections explain gear choices such as gauges, tanks, compressors, and regulators, while others describe earth sciences and diving.

The best way to describe the scene is similar to heat waves that rise off of hot pavement as divers pass through the boundary into a warmer layer of saltwater.

The best way to describe the scene when divers pass through the boundary into a warmer layer of saltwater is to think of the heat waves that arise from hot pavement.

After slipping underwater a short swim brings the diver into another world.

After slipping underwater and swimming a short distance, the diver enters another world

The day when a diver can press a simple button to call for help sits on the horizon is taking shape on the drawing board.

The day draws close when a diver can press a simple button to call for help.

The region is one of the few places on earth where alluvial copper is found in quantity, and, according to some researchers was the source for the metal that helped usher the world into the Bronze Age.

Some researchers say that as one of the few places on earth where alluvial copper is found in quantity, the region was the source for the metal that helped usher the world into the Bronze Age.