The work of Linnaeus,5 and the passion for rarities in gardens, made planthunting fashionable and important: pupils of Linnaeus undertook voyages and travels in search of plants for him to name, and many of them died, martyrs to science. Natural history and astronomy accompanied each other, bringing geography and Halley’s terrestrial magnetism along with them, embodied in sailors who had acquired special skills and in civilian passengers, as survey voyages opened up new trade routes – naming and claiming coasts and islands as they went. Expeditions also went overland, as the Americas, Siberia, Australia and Africa were opened up – again by the military (notably the topographical engineers in the USA), by empire-builders, by hunters after big game, by goldseekers, by missionaries like Dr Livingstone, and in the later nineteenth century by intrepid women like Isabella Bird, Mary Kingsley and Marianne North.