It will reveal the extraordinary and unacknowledged debt W B Yeats owed to his sisters, who supported him financially and personally published the first editions of his books of poetry.
The book is a story of two talented women, one a printer and painter and the other a skilled embroiderer for William Morris, who were oppressed by poverty and bound together despite mutual dislike.
The Yeats Sisters by Joan Hardwick is a story of frustration and cruelty. Lolly was falsely accused of madness by her family and Lily - who disliked her intensely - was forced to live with her until death. They were part of a dysfunctional and divided family. John, their father, had trained as a barrister but took up painting. His inability to make money condemned their mother, Susan, to lifelong hardship.
The couple's four children endured a childhood darkened by their parents' unhappiness and frequent moves between Ireland and a succession of increasingly dingy houses in London.
William, their first-born, went on to become Ireland's most celebrated poet, winning the Nobel prize in 1923. Jack, six years younger, became a famous painter. But life was less rewarding for Lily, born in 1868, a year after William, and Lolly, two years her junior.
The problem for Lolly (her real name was Elizabeth) was her energetic personality, which overflowed in nervous mannerisms. She longed for love but was regarded with irritation, particularly by her father and elder brother. "My sister Elizabeth and I quarrelled at the edge of the cradle and are keeping it up to the grave's edge," William once said.
Lily was a different type altogether, according to the book, to be published by Pandora on 8 January. Christened Susan, after her mother, she was languid and deferential to men.
As a result of their father's inability to make money, both sisters had to earn a living at a time when well-bred girls were usually supported by their fathers or husbands. Lily took work as an embroiderer for William Morris and Lolly trained as a nursery school teacher. It was their income that for years maintained the household of six adults.
Both hoped they would marry. But Lily had no offers and although Lolly fell in love with an academic called Louis Purser, it ended in disaster when he kissed her farewell one night and she jumped to the conclusion that they were engaged.
Their situation changed in 1902 when a friend named Evelyn Gleeson suggested the sisters join her in an Irish craft business that only employed women. Dun Emer in Dundrum was the result.
It consisted of an embroidery department run by Lily and a press run by Lolly, with the capital put up by Evelyn. The first book published was In the Seven Woods, one of William's early books of poetry. But although the venture made money, Lolly and Lily fell out with Evelyn.
In 1909 they set up on their own as Cuala, and under this imprint Lolly again published her brother's writing - including Poetry and Ireland and Responsibilities - as well as work by Ezra Pound and J M Synge.
Such was the fame of Lolly's work that it warranted a mention, albeit somewhat unflattering, in James Joyce's Ulysses. Buck Mulligan remarks: "Five lines of text and 10 pages of notes about the folk and fishgods of Dundrum. Printed by the weird sisters in the year of the big wind."
William Yeats was editor of the press, with responsibility for choosing books to print. But he lamented the necessity of finding books "to feed my sister's hungry press", although its profit was the sisters' livelihood.
Later, in his autobiography, he gave the impression that he had only one rather shadowy sister on the fringes of his life. "Lolly was hardly mentioned," Joan Hardwick notes in her book.
As she grew older Lolly was pushed out of family life; the unkindness became cruel when she reached menopause: the family conspired to suggest she was going mad and persuaded her to spend her evenings in bed. "Like many a family before them they had, metaphorically, confined the madwoman to the attic. They were free to spend their evenings talking and laughing by the fire," the biography records.
She died in 1940, followed nine years later by Lily. In death, as in life, they were not to be parted. They share a grave by the church of St Nahi in Dundrum.
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