As a biographer of Livingston and author of another period novel ("Until the Colors Fade") set in 19th-century England, Tim Jeal has established himself as someone who knows well the tone and texture of Victorian life. So it is not surprising that "A Marriage of Convenience," set in 1860's England, reveals his ability to move his characters across the scenery with a careful eye for detail.

There are varied worlds: the town house and brokerage firm milieu of Esmond Danvers, the elder, illegitimate son of a duke, who is, because of his birth, a self-made man; the swaggering, clubby, military circles of Clinton Danvers, his younger brother - more dashing, legitimate, the possessor of the title; and the theatrical backdrop for Theresa Simmonds, the actress they both love.

A novel of less serious intentions would be overpowered by the wealth of detail Jeal includes. For the most part, however, "A Marriage of Convenience" stays afloat, only occasionally foundering in a plot made more complex by the author's tendency to tell, rather than show, what is happening.

The story, of course, is of a love triangle: two brothers - one successful but dull, the other dashing, but poor - both rivals for one woman. It is Clinton who steals Theresa away from Esmond and marries her in an Irish ceremony he knows to be illegal under English law.

Later renouncing this "marriage of conveninece," even though he still loves her, Clinton becomes engaged to an heiress in order to save his fiscal neck.

Along the way, the action gets bogged down in confusing financial complexities leading up to Clinton's ruin. And then, when he seems almost saved by his second "marriage of convenience," there is a tedious trial to establish the validity of the first one.

Although he makes a dashing and sexy centerpiece for the novel, Clinton is a problematic protagonist, who fails finally to move us because of his essential weakness. His strength is of the blood and thunder variety - more obvious when charging guns in the field than facing moral choices on the domestic front. His weakness is the old stock of tragedy - hubris. As his uncle, to whom he goes for money, says: ""You're such a positive man that I can't help finding a little humor in it.""

As for Esmond, he exists primarily as a plot device. In addition to playing the role of fraternal rival, he holds the purse strings of the story and jerks them at appropriate intervals to send the action and Clinton's fortunes racing toward a particular (mostly downward) direction.

In Theresa, Jeal has drawn a far more successful character. Consistent, assured and beautiful, she makes the novel live. Already a widow and the mother of a young daughter when we meet her, Theresa is a woman of experience, a character who has had to cope with a fair amount of adversity before she encounters Clinton. Far stronger than he, she never quite sees that deep down Clinton is a shallow man. We close the novel of their fatal attraction with a faint hint of irritation that, wise as she is, she lacks this insight. By the time we reach the conclusion (which I assume Jeal meant to be tragic), we can feel only dismay. There is pathos here, even absurdity, but precious little tradegy.

"A Marriage of Convenience" overreaches its grasp. Its action - shaped as it is along tragic lines - doesn't grow naturally out of its characters. Instead, this serious, complex tale of difficult moral choice is superimposed upon a group of figures, most of whom are incapable of sustaining its weight.