Francis Beaufort was born in 1774. His family, originally called de Beaufort, was of French Huguenot extraction and had settled in Navan, Co Meath.
At the tender age of 14, young Francis went to sea, and in the course of his many voyages thereafter he was struck by the difficulties caused by the lack of a standard method for assessing wind-speed.
Terms such as light airs, stiff breezes and half gales were in common use among the maritime community, but they had no universally accepted meanings, and misunderstandings and ambiguities were rife.
Beaufort approached the subject scientifically. He decided that wind needed to be assessed against a well-known standard, in much the same way as a standard unit might be used to determine the length of a familiar object.
He selected as his "standard" the typical full-rigged man-o'-war of the British navy, and he defined what we now know as the Beaufort Scale by effect of the wind on such a vessel - and in particular by the amount of sail it could carry in high winds without getting into trouble.
A light air, for example, which he called Force 1, was a wind just sufficient "to give steering way". A moderate breeze, Force 2, was a wind such that a "well-conditioned man-o'-war, under all sail and clean-full, would go in smooth water at from 5 to 6 knots".
With Force 8, a whole gale, the same ship could only bear "close-reefed main topsails and a reefed foresail". And the highest number on the scale was Hurricane Force 12, when a man-o'-war could show no canvas whatsoever.
The Beaufort Scale of Wind Force began to be used officially by the navy in the early 1830s, and its form has changed only cosmetically over the last 150 years. A new version was introduced in 1906, when men-o'-war were becoming few and far between, to describe the force of the wind in terms of its effect on the sea itself, rather than on a ship.
An alternative version for use on land was devised later to indicate the corresponding effects on trees and buildings.
Rear Admiral Sir Francis Beaufort retired from the navy in 1855 at the ripe old age of 81. Shortly afterwards he moved from London to spend the remainder of his life in a pleasant cottage near the sea at Brighton, where in his declining years he delighted to be wheeled along the promenade. He died peacefully in his sleep early on December 17th, 1857, 140 years ago today.