5 January 1800, Alma Whittaker is born into a perfect Philadelphia winter. Her father, Henry Whittaker, is a bold and charismatic botanical explorer whose vast fortune belies his lowly beginnings as a vagrant in Sir Joseph Banks’s Kew Gardens and as a deck hand on Captain Cook’s HMS Resolution. Alma’s mother, a strict woman from an esteemed Dutch family, has a knowledge of botany equal to any man’s.

It is not long before Alma, an independent girl with a thirst for knowledge, comes into her own within the world of plants and science. But as her careful studies of moss take her deeper into the mysteries of evolution, the man she comes to love draws her in the opposite direction – into the realm of the spiritual, the divine and the magical. She is a clear-minded scientist; he is a Utopian artist. But what unites this couple is a shared passion for knowledge.

The Signature of All Things is a big novel, about a big century. It soars across the globe from London, to Peru, to Philadelphia, to Tahiti, to Amsterdam. Peopled with extraordinary characters – missionaries, abolitionists, adventurers, astronomers, sea captains, geniuses and the quite mad – above all it has an unforgettable heroine in Alma Whittaker, a woman of the Enlightened Age who stands defiantly on the cusp of the modern.