Reminiscences of a prodigious literary generation;

Assault on Mount Helicon: A Literary Memoir, by Mary Barnard. Berkeley: University of California Press. 331 pp. $19.95.

your age is to get a technique. If you don't sweat at that now you will find yourself, like me, at nigh onter fifty still learning what I ought to have learned at 17.

Thus wrote Ezra Pound to Mary Barnard in 1934. Mary, the product of a secure and literate Northwest childhood, had sent her first letter to Italy the year before. She had sent Pound six of her poems, because she thought ''he knew more about the technique of writing poetry than any other living poet.'' Their correspondence began a rare and enviable literary mentorship and is generously quoted in Mary Barnard's memoir, ''Assault on Mount Helicon.''

The awkward and off-putting title of the book is a typically cryptic quote from Pound: ''You hate translation??? What of it?? Expect to be carried up Mt. Helicon in an easy chair?'' It should not, however, discourage Barnard's readers from continuing. Her memoir is an unsentimental yet affectionate portrait of New York's literati of the '30s and '40s, a ''My Sister Eileen'' of the intelligentsia. It is clearly not an autobiography (much personal information is omitted) but is a fine description of the literary world through which Barnard relentlessly plodded.

As the only ''rhyming poet'' at Reed College, Barnard learned by observing what others did not know. She went to New York and took hack jobs in order to be in the center of the literary world. She exemplified the myth of the starving poet, renting a furnished room for $4 weekly and saving her pennies for the hat necessary for attendance at literary teas. She adhered strictly to Pound's advice and dedicated herself to her craft, although she also pursued making connections with all the necessary people.

''Pound believed strongly in the value of cross fertilization, exchange of ideas, the stimulation to be had from talk with another writer even if it was quarrelsome,'' she writes. ''Digging one's own little burrow and crawling in with a book or with one's own manuscript was not enough. The English, he said, at least had sense enough to eat once a week or once a month with people they didn't particularly like in order that life and letters might persist.''

Barnard developed a friendship with William Carlos Williams when he enthusiastically replied to her first letter. Years later, he described a similar reply he was sending to a mediocre poet. When asked why he was encouraging someone without talent, he replied, ''Oh, I always do. ... It makes them feel good!''

Barnard was fortunate enough to spend two summers at the artists' retreat Yaddo. With a surprising lack of criticism, she describes in her memoir the many writers and painters she was able to meet. Despite her self-admitted provinciality, she managed to be on good terms with many of these successful and sophisticated people (some of whom were not on good terms with each other), perhaps because of this lack of personal criticism.

''... I have never excluded from my friendship people with whom I disagreed about something, or even most things,'' she confesses. ''It would have been a lonely life.'' She was encouraged by many of these colleagues, and she was praised, which may account for the security that allowed her to experiment and persevere despite limitations and failures. Her attempts at fiction came to nothing, and after much searching even her poetic ambitions became more realistic: ''I had come to the conclusion that a poet had to run very fast indeed to stay in the same place - that is, in the public eye and memory - faster than I would ever be able to run.''

Economics often dictated her circumstances and her projects. Forced to move home to Vancouver when her funds were exhausted, Barnard was out of touch with the New York Public Library, so she spent more time writing than researching. She did, however, return to New York as soon as possible. She endured the depression and World War II, then enjoyed the postwar surge of interest in poetry. Struggling to find her niche, she landed in a hospital and spent months recuperating by learning ancient Greek. With Pound's belligerent encouragement, her experiments with Greek lyric and verse forms led to her ''Sappho: A New Translation,'' probably the only work for which she is remembered, until now.

''Assault on Mount Helicon'' portrays a close-knit and dedicated literary circle, a camaraderie hardly possible 50 years later in our era of mass-marketed talk-show authors. The literary world, much smaller then, maintained a sense of publishing integrity and scholarly sensitivity rarely encountered today. But Barnard escapes nostalgia. She quotes her own letters, shows us photographs she took in her travels, and quotes from many previously unpublished letters she received, from Pound and Williams especially.

Her memoir is entirely readable, often humorous. Of Pound and Eliot she recalls, ''(Pound) said that when they first met in London in 1914, Eliot was attracting attention by his bizarre behavior. Pound, by his own account, said to him: Look, I'm playing the wild man; why don't you do the other thing? Why don't you play the ultra respectable, polite and precise young man? So he did.''

While some of the many names recalled may not have achieved household-word status, the advice Barnard was given remains sound and almost folksy today. The important thing, we are reminded sensibly, is to get on with it. However difficult art is, one must persist. Despite her domineering mother, Marianne Moore wrote. Despite families and financial obligations, writers write. Of her ever faithful literary agent, Diarmuid Russell, she says, ''He gambled on me and lost, but his faith in my potential persisted. One of the last times I saw him, he said to me, 'Some day, Mary, you are going to do something - I don't know what it will be, but SOMETHING - that will have the publishers dancing around you and bringing you your breakfast in bed!' ''

Although I can't envision the editors of the University of California Press climbing Mary's stairs with a breakfast tray, ''Assault on Mount Helicon'' is a lovely reminiscence of a strong, vastly productive generation.

Elizabeth Chamish is free-lance writer living in California.