BOOK REVIEW : Literary Marriage Binds Author, Agent for 30 Happy Years : AUTHOR AND AGENT: Eudora Welty and Diarmuid Russell <i> by Michael Kreyling</i> ; Farrar Straus & Giroux $19.95, 198 pages

The beginning of a partnership between author and literary agent raises at least as many hopes as the beginning of a marriage. Anyone with author-friends knows that author-agent affairs go down in flames as often as marriages.

Intense expectations in either case are usually too hot not to cool down. Of a potential agent or spouse one can think: Here is someone to protect me from the outside world. Here is someone who will be increasingly happy as I am increasingly successful. Here is someone who will make me better than I am.

“Author and Agent” chronicles 30 years of harmony--an author-agent relationship to rival the marriage of Will and Ariel Durant. Diarmuid Russell, son of the Irish poet known as A. E., and just starting out as a literary agent after immigrating to the United States in 1929 and working for publishers, was an appreciative and tender first reader for Eudora Welty.

She, 32 when they met by mail, was an innocent, born and raised in Jackson, Miss. (where she lives still at 81). She’d gone up to the University of Wisconsin and Columbia University, found the North too cold and returned happily to live with her parents, near her two brothers. She was in no hurry to make her name or fortune; her first published story went, free, to a tiny magazine when she was 26.

Beginning in 1941, Russell shepherded five collections of Welty stories and four of her five novels to publication. He died in 1973, at 69. Michael Kreyling, an English professor at Vanderbilt University in Nashville, author of a scholarly work on Welty, has gathered a nice selection of three decades of letters between Welty and Russell.

It starts with this one:

“Dear Miss Welty,

John Woodburn of Doubleday’s has suggested that I write to you to see if you might need the services of an agent. I suppose you know the parasitic way an agent works, taking 10% of the author’s takings. He is rather a benevolent parasite because authors as a rule make more when they have an agent than they do without one.”

About half the literary agents working today still make 10%; most of the others get 15%. The jaded modern reader’s one complaint with this elegant, respectful book is the absence of lust and greed. Faxes between Joan Collins and 15-percenter Swifty Lazar do not read like this.

In style, Welty is the Virginia Woolf of the Mississippi Delta, or the Natchez Trace. Her stories work by observing characters, events and conversations in an oblique way.

Her work can seem casually impressionistic and sometimes puzzling; it takes someone who is just as subtle as Welty is to understand the calculation and care underneath. Even in 1941, obliqueness and impressionism didn’t spell blockbuster.

The first year of letters tracks rejection after rejection. As the stories we think of now as classics got turned down repeatedly, Russell’s faith persisted. His heartening message to his writer: “You could never do anything bad.”

Suggesting that one turn of plot is obscure, he writes: “There is no use in having an agent unless you allow him to be as honest in comment as he must be in money matters. If the comment seems unjustified, you dismiss it and write the agent a letter calling him an unliterate ass.”

Welty never took him up on the offer to call him an unliterate ass. In fact she was amazingly undemanding. “I shall never be bitter if you do not sell the stories, but only struck with the weight of your influence if you do.”

It was particularly hard trying to sell stories by an author with no desire to write a novel. Welty didn’t see why she should be driven from writing stories and made to slave at something she didn’t like.

“You can write what you wish,” responded Russell, “and all I will ever do will be to tell you what I think of the quality.”

When her satirical masterpiece, “Why I live at the P.O.” was speedily sent back by the New Yorker, Russell wrote: “My irritation with the editors is not only on your account but has now also become a personal matter with me. Either they are wrong or I am wrong and I am not accustomed to being wrong . . . “

At the end of seven months of toil on Welty’s behalf, Russell was finally rewarded with a sale--the story “Powerhouse” to the Atlantic. He made $20.

Welty and Russell went on to fat sales to the New Yorker and fatter deals for books with Harcourt Brace Jovanovich and Random House, O. Henry Awards, a Broadway version of one novel and even a flutter with Disney Studios.

“Author and Agent” is a charming celebration, and Kreyling tactfully refrains from speculating about Welty’s love affair with a Mississippi writer living in San Francisco or wondering whether she was so patient every damned minute.

Kreyling takes at face value Russell’s deploring of the “cheap and shoddy” methods of publishing after 1960 and is infinitely sympathetic to a man who loved his job though he never made enough money to buy a house.

Welty and Russell shared a kind of perfect communication which, because they wrote rather than phoned, is saved. Perfect communication is the impulse behind literature and the hope and occasionally the accidental achievement of marriage.

As an expression of trust and love, Welty’s letters to her agent are right up there with any missive from Elizabeth Barrett Browning to Robert.

“If you keep telling when what I write is clear and unobscured and when it is not, as it appears to you, then I will have something so new to me and of such value, a way to know a few bearings. Is this what was in our contract? I didn’t understand it would be so much.”

Next: Jonathan Kirsch reviews “The Edge of Paradise: America in Micronesia” by P. F. Kluge (Random House).