Windswept_ The Story of Wind and Weather - Marq de Villiers [64]
"Hereafter," he wrote in his journal (now kept in a box in a filing cabinet in the Met Office in London), "I shall estimate the force of the wind according to the following scale, as nothing can convey a more uncertain idea of wind and weather than the old expressions of moderate and cloudy, etc." The scale he devised ranged from o, calm, to 13, storm. Within a few years he had allocated the numbers more specifically, to relate them in a way that sailors everywhere would understand. He had reduced the categories to twelve, which ranged from "light air, or just sufficient to give steerage way," through breezes and gales to "hurricane, or that which no canvas could withstand." (For the full Beaufort scale and other wind measurements, see Appendix 2.)
Sir Francis Beaufort
So useful was this scale that by 1838 it was made mandatory for log entries in all Royal Navy vessels, and civilian vessels soon followed suit. One of the first recorded times the scale was put into daily practice was on Darwin's voyage on the Beagle.
Beaufort went on to become official hydrographer to the Admiralty, and died in 1857. His obituary made much of the charts he had devised for the Admiralty, and of his splendid work in ensuring safe passages for vessels everywhere, but made no mention whatever of the Beaufort scale. It was just one of his chores, something useful he did along the way. Useful, but at the time not worth recording.13 It is still, however, being used, in one form or another. The curious thing about Beaufort's original scale is that it doesn't mention the wind speed. The only velocities mentioned are those that might ordinarily be achieved by a man-of-war under full sail at various conditions—Beaufort wanted his readers to look at the ship, not the wind. His numerical system was entirely arbitrary, but the ship's behavior each number was attached to was not—his descriptions would have been very well understood by sailors who had spent years in vessels similar to the Woolwich. They were all Royal Navy men who had put in their time blockading Europe and ranging to Africa and the Indies in sailing ships with quite recognizable characteristics. Beaufort's descriptions are couched in terms of the ship's behavior under sail—the first four for how easily a ship could be propelled, those of five through nine in terms of her sail-carrying capacity, and the rest for mere survival at sea.
The scale jumped from this—a shorthand reckoner for experienced sailors—to something still used by weather offices because of two small technological improvements and one accident.
The two gadgets were the first practical telegraph, invented by Samuel Morse in 1835, and the cup anemometer (wind gauge) invented by T. R. Robinson in 1846. The accident was more than just a small accident—it was a naval catastrophe.
In the fall of 1854 the French and English—for once on the same side—were fighting at Sebastopol when the fleets transporting almost all the supplies they needed for the coming winter siege were struck by a sudden savage gale. On the morning of November 14, the English lost no fewer than twenty-one supply ships, and the French almost as many, a maritime disaster that was rivaled in its intensity only by the almost complete destruction of a French invasion fleet aimed at New England more than a hundred