The letters between the two start with a "Dear Miss Frame" in March 1954, soliciting a particular poem for Landfall and any other work, poetry or prose.
Her reply, "Dear Charles Brasch", is guarded. His next letters start with "Dear Janet Frame".
They don't drop second names from the "Dear" until their ease with one another grows after six months.
Over the years her tone moves from awkward self-effacement to restrained confidence, while his moves from caution to, well, kindness rather than warmth because of his reserved personality. She writes about that to others.
But what strikes me most forcefully about this enlightening correspondence is what a deeply decent and generous man Brasch was.
Early in their exchange he was never less than polite in his response to her work, but never less than honest either.
He was a wealthy man, heir to a family fortune, and an arts patron of the most extraordinary tact. Frank Sargeson was always short of money in his early days living in his Takapuna bach and he received regular, anonymous gifts of £50 which almost certainly came from Brasch.
The way he managed to give money to Frame over the years without making her feel too guilty was beguiling.
He discussed guilt with her in a light-hearted way calculated to ease her conscience, but as the letters make clear she understood what it was all about. He soon recognised her acute intelligence and observed that she was "so quick, receptive, all her antennae alive, aware".
Brasch was a considerable poet and man of refined cultural sensitivity who could easily have lived in comfort in Europe. He chose not only to stay in New Zealand but campaigned ceaselessly to promote arts and letters. He backed Landfall financially and, as unpaid editor, made it the country's pre-eminent literary magazine.
He was tireless in his attempts to encourage successive governments to set up a Civil List on the English model to provide pensions for writers and artists who had contributed to the national culture and never earned enough to provide for themselves.
At one stage in their 20-year association Frame writes about Brasch to her close American friend, Bill Brown, and describes him as "a noble, upright old man with discipline instead of marrow in his bones". But you find out when he dies, from her beautifully expressed grief, how much his support and muted affection had come to mean to her.
I exchanged letters with Brasch once and his was charming, encouraging and perceptive.
From that and other more distant observations I thought of him as my kind of role model, a person I felt sure brought few if any self-serving attitudes to his relationships and judgments.
So, I enjoyed this engaging book for what it contained, instructive as it is about both personalities, and for the craftsmanship of the people involved in making it.
It has an attractive, linen-finished cover, and a clear typeface on lovely paper; so it looks good, feels good and smells good. A beautiful example of the book as artefact.
A shame to find a typographical error, though, which ought not to happen in a book of this quality.
Gordon McLauchlan is an Auckland writer.