'She's there in that gathering of ghosts I carry with me' - author Doireann Ní Ghríofa on the 18th century poet who has haunted her since her teens

When Doireann Ní Ghríofa tells me she wrote most of her prose debut in a car park, my surprise is fleeting. A collection of personal essays doubling as an extraordinary literary detective story, A Ghost in the Throat is so impeccably crafted, so beautifully generous that at first it seems incongruous to imagine it emerging in a multistorey over a supermarket. But actually Ní Ghríofa's workspace fits perfectly with the book, which is partly a meditation on motherhood and domestic labour.