Penelope Gilliatt's new novel is something of a tease. It is shot through with high purpose and flashes of wit, but the reader must dig and sift for meaning at every turn, making the whole exercise of appreciation much more laborious than the author could have intended. Penelope Gilliatt is well known, after all--as befits a writer in The New Yorker--for her swift, crisp, piercingly intelligent style. What makes "Mortal Matters" so disappointing is not that she abandons her usual quirky voice, but that she lets the quirkiness run on unchecked, somewhat as if this were the exuberant first draft of a good novel rather than the disciplined end product one has come to expect.

It is doubly disappointing in that the raw material of "Mortal Matters" offers--or offered--such arresting possibilities. Like all Gilliatt's stories, it begins in medias res with a largely eccentric cast of characters caught up in hilariously improbable situations, which yet seem to resonate with familiar moral, and mortal, concerns.

Lady Averil Corfe is the 80-year-old widow of a Northumbrian shipbuilder, and a Northerner herself, living unhappily in London with her vain, faithless, all-too-modern son, Tony; his ill-used wife, Eliza; their neglected young son, Tony; and assorted provincial domestics. Presently, however, the focus zooms in on Lady Corfe, who, with the courage born of desperation, takes a train journey back to her native Northumberland and thus, in a manner of speaking, to the past. The book returns with her to the early years of the century and gradually plots her life up to the present, when she comes back to London and is able to face with renewed grace the apparent inanities of her contemporary family.

There are some obviously fine things in this story. With her unerring eye for the telling detail, Gilliatt gives us a moving view of old age. "Averil sat down on a footstool and rested her chin on her hands, her cane between her knuckles, as if it were her better limb." She captures the peculiar loneliness of little boys, Simon "practicing on his skateboard to the ruination of the polished floor" and the unique misery of the rejected wife "speaking rapidly to herself in what she knew would be an unheard monologue."

Above all, there is the intrinsic interest of the novel's central premise, the juxtaposition of generations, which Gilliatt uses to draw a delicate line of contrast not only between past and present but also between provincial industrial Northumberland and the great cosmopolitan melting pot of London. Not surprisingly, all that is rooted and solid and fine is found in the past and the provinces, and all that is brittle, rotting and false holds sway in the modern city. Despite the comparative unoriginality of this idea, "Mortal Matters" is an attempt at social history, with fiction as its cutting edge (to borrow the title of Gilliatt's last novel), no less serious in intent than many a scholarly period study.

Unfortunately, good intentions are no guarantee of success. Several things go wrong with the novel. In the first place, much of the account of Lady Corfe's life is made up of large, unassimilated chunks of historical fact or anecdote, covering everything from suffragettes to shipbuilding, often quoted verbatim from contemporary sources. Even more distracting is what I referred to earlier as the unchecked quality of the language. Gilliatt has always written very high-class English, literate and lapidary, with her mastery of the aphoristic throwaway line and her ear for dialogue serving as her virtual trademarks as a writer. It is a pity, then, that in "Mortal Matters" this polished, Latinate, aphoristic quality should have been developed to a point where the reader is either seriously delayed, trying to plumb the meaning, or else left in the dark altogether. Here is a passage describing Tony at the age of 4:

"He adored making beloved men of the unloved and to know that the craft was his. His character, still in the making and sometimes of sharp worry to his parents and adult friends, seemed to strangers to be founded in infant goodness, an instinct for the beneficent that was almost premoral. Few but his parents, tardy to find fault but in this case all too swift to mourn, saw in his baby acts of courteous divinity the roots of a man who could be engaged in excellence but be not totally the more attractive for it."

Well, yes; but the sustained effect of this kind of writing is one not of profundity but of caricature. Even the characters' own speech is infected. From Lady Corfe on down to the night-sleeper attendant on the London-Newcastle train, they all seem to sound the same, which is to say as if Penelope Gilliatt engaged in parodying her own most distinctive virtues.

"Mortal Matters" is, in sum, a fascinating example of a-good-book-somewhere-in-there-trying-to-get-out, fatally imprisoned by its own style.