Fiction Chronicle.

AUGUST By Gerard Woodward. Norton, paper, $14.95. It doesn't seem possible Woodward would allow anything bad to happen to the affable members of this slightly eccentric English family, whose lives he details over the course of 15 years. That the years happen to be 1955 through 1970 offers a clue, though, that at least a few of them are going to have trouble adapting to a world where solid British manners are being tested by modernity. A good-natured art teacher named Aldous Jones looks forward each year to the month when he, his wife and children can vacation in the Welsh countryside, their arrival ''a cataloging and celebration of sameness'' that anchors them spiritually. But when his son Janus -- an aptly named piano prodigy who can't keep his creative and destructive halves in balance -- begins to fall apart, the aftershock sends another family member seeking chemical comfort, leaving Aldous to wonder whether ''the territory of madness is entered by a doorway of crystallized normality.'' Some readers may already know what becomes of the Jones family, as this novel is the first in a trilogy whose American publisher strangely saw fit to release the second and third volumes, ''I'll Go to Bed at Noon'' and ''A Curious Earth,'' before this one. No matter. What ultimately becomes of the Jones family may not be a mystery, but how it all happens is the stuff of great, if sad, suspense. [ABSTRACT FROM PUBLISHER]