Clouds: How Luke Howard linked Weather Lore and Natural Philosophy

William Wordsworth’s (1770-1850) ‘lonely as a cloud’ poem was conceived in April 1802 on a spring day walk in the Lake District. A few months later, in December 1802, a pharmacist and amateur meteorologist, Luke Howard (1772-1864) delivered a paper in London, on the dynamics of cloud formations. The two events were unrelated but their futures became intertwined. Howard’s essay ‘On the modifications of Clouds’ (1803) resonated deeply within learned circles, including arts and sciences. Clouds soon became the objects of fascination and scrutinizing attention. Articulating the order of the enigmatic sky-scape inspired poets, painters and scientists. The "lonely as a cloud" simile in Wordsworth’s poem, which he composed and published (1807) years after his Lake District walk, is also a nod to Howard’s ideas. Within sciences a century later, the International Cloud Atlas (2017) of the World Meteorological Organization still draws on Howard’s taxonomy. What is it about Howard’s approach to clouds that made his essay so influential? Various characteristics have been identified so far; a few are highlighted here