A mammoth first novel called

Dancing on Thorns by British author

Rebecca Horsfall made substantial sales last week to Random branches on both sides of the Atlantic: its enthusiastic purchasers said it combines the women's-saga allure of Rosamunde Pilcher with the contemporary savvy of Britain's Jilly Cooper. The buyers of the 1,000-page epic with a ballet background were

Allison Dickens at Ballantine here and

Kate Elton at Random/Arrow in London; Dickens bought the book for North American right from

Paul Marsh, representing

Judith Chilcote in the U.K. Publication is planned for next spring, in hardcover here and trade paper in London, with later mass market editions in both countries. Author Horsfall grew up in an Anglo-American theatrical family, has worked as a producer-director in the West End and took 10 years to write the novel—part of that working in two different ballet companies to get her backgrounds right.