In this story from my collection Sleepytime Cemetery, our two hapless protagonists contend with life underwater. Why is it so much harder to breathe there, anyway? Here’s how it begins…

INTO THE SEA

“I’ve never done this before,” admitted Morris.
“Me neither,” said Winchell.
“Well, let’s see what it’s like,” said Morris.
They jumped off the cliff and into the sea.
“I thought it would be warmer,” remarked Winchell, as they sank into the blue-green depths.
“It’s kind of cold for such a hot day,” said Morris.
“Not unpleasantly so,” said Winchell.
A ray flapped toward them from below, veered away, and swam off to their left, gradually disappearing into the opalescent murk.
“But now my clothes are all wet,” said Winchell, gazing in dismay at his billowing shirt and pants. “I should have thought of that.”
“And it’s hard to breathe, isn’t it?”
“Well, there’s no air down here.”
“But water’s just hydrogen and oxygen,” said Morris. “Why isn’t it like air?”
“It’s in liquid form,” explained Winchell. “You have to boil it to make it a gas.”
“Nonsense,” said Morris. “The air outside is hydrogen and oxygen, but it’s not boiling. It’s warmer than this water, but it’s not boiling.”
“It has other stuff in it too, like carbon dioxide,” said Winchell.
“That shouldn’t make any difference,” said Morris.
“And the sea has salt in it, too,” Winchell added.
“That doesn’t matter either. When you pour salt on land, the air doesn’t liquefy,” Morris objected.
“True,” admitted Winchell…