Some of the most ravishing descriptions of the sea being whipped up into a tempest are contained in an empirical scale of wind force as encountered on sea and on land, the modern Beaufort scale. Escalating from zero, “Calm” (“Sea like a mirror; smoke rises vertically”), up through “Fresh Breeze,” “Gale,” “Storm” and so on, it goes on to a hurricane force of 12, where the “Sea is completely white” and “debris and unsecured objects are hurled around.” The observations have the keen-eyed perceptions of a poet: “well marked streaks of foam are blown along the direction of the wind,” “small flags extended,” “dust and loose paper raised.” The scale is in fact a favorite with poets, Don Paterson’s “Scale of Intensity” being perhaps the most successful homage. Alongside the stranger symptoms in Paterson’s scale, such as the change in weight of ordinary objects, or reversed vortex in the draining bath, Paterson makes sure to begin “Sea like a mirror” and to end on that paradoxical phrase of howling violence and visual stillness (one imagines a Turner painting), “Sea white.”
While the Beaufort scale is still named after Sir Francis Beaufort, upon whose 1805 scale the modern one is based, his observations had a nautical briskness and reflected not the wind’s effect on the sea, or the land, but on the sails of a British Navy frigate, from calm and “or just sufficient to give steerage way” to hurricane, “or that which no canvas can withstand” (poetic phrases which incidentally tend to natural iambic pentameters).
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