The Alchemy of Air (Book)

On gunpowder

• Because every barrel of gunpowder required three-quarters of a barrel of saltpeter, access to saltpeter became a matter of national survival.
• In 1626 England’s King Charles I commanded his subjects to “carefully and constantly keep and preserve in some convenient vessels or receptacles fit for the purpose, all the urine of man during the whole year, and all the stale of beasts which they can save” to be donated to the saltpeter plantations
• The mother lode of saltpeter, however, the only natural deposits in the world large enough to feed the gunpowder needs of an entire nation, was discovered in the mud flats of the Ganges in India (where it was believed that a combination of the river water, the hot climate, and the dung of holy cows combined to create a sort of huge natural saltpeter plantation). The British East India Company started shipping it to England by the ton in the mid-seventeenth century—it was one of the company’s most important cargoes—and this vital natural resource made India an especially important target for European colonial expansion. Saltpeter was a significant factor in favor of the British takeover of India.