There were two races to record and observe the transit of Venus across the Sun in the 18th century – in 1761 and 1769 – and both show, as Wulf points out in her pacy yet informative account, "a century in which science was worshipped". Worshipped so much that men were happy to risk their lives for it.
Well, some men were – Charles Mason and Jeremiah Dixon (their mapping of the border between the Southern and Northern states of America is reflected in the naming of the "Mason-Dixon line") were on a ship caught in battle with the French on their way to Bencoolen, an observatory point in Sumatra. So traumatised were they that they refused to carry on. The Royal Society threatened them with court and the Admiralty with charges of mutiny.
Science didn't always advance with threats, though: this history is as much a testimony to the characters who undertook foolhardy tasks as it is to scientific progress. The remarkable Jean-Baptiste Chappe d'Auteroche, for example, made a 4,000-mile journey from Paris to Siberia during the first transit. His second journey took him to California – he was the only man to observe both transits from beginning to end. Wulf highlights the links between commerce and science (the investment of the East India Company in the first British expedition), the importance of countries co-operating with one another, and the input of the state (the enthusiasm of the monarchy for scientific expeditions helped release funds). But her story belongs to the fearless – and the fearful – individuals who endured hostile terrain and conditions in the name of science.