Newbie question


First, a confession: I am not a sci-fi junkie. :)

I hope you guys can help me identify a short story I read nearly twenty years ago, in an anthology.

The premise of the story was a society of human-like beings whose planet, for reasons I can't recall, was no longer habitable. They collected their own DNA, altered it, and re-introduced it into the ocean to "evolve" back into beings which could breathe and live in the water. Like all intelligent beings, the new beings wondered about their origins. They had some records from their "creators" but because the records had been partially lost or damaged, there were many unanswered questions. One particular thing I recall is that they had knowledge (from the books) of chemistry, but were unable to practice it because the chemicals would float away whenever they'd begin an experiment; this lead them to believe that they had once lived on land.

It was wonderful story and for the better part of two decades, I've tried in vain to remember the title or author.

If anyone here can help, I would be most appreciate.




This is news, Vincenzo, NEWS!
short story 'surface tension' similar; the humans reconfigure their dna into microscopic aquatic creatures; at one point they make a 'spaceship' to travel to another puddle! they munch on diatoms and live in fear of somethings (hydras?)

in Wikipedia; author James Blish. actually written in the 50s, but in tons of anthologies (I first read it in early 70s)