London, 1803 and 1865 · Luke Howard, On the Modifications of Clouds
Writing the Sky
Luke Howard, a chemist who had kept weather journals since he was ten, was the first to give clouds a system of names: cirrus, a curl of hair; cumulus, a heap; stratus, a sheet; and nimbus, the rain cloud. We still use them. The Public Domain Review's piece is on the third edition of his essay, printed in 1865, the year after he died.
On page 14 he offers something else: a way to write clouds down. Each of the three basic kinds gets a stroke. Mixed clouds are written by putting the strokes together.
As printed in 1865, page 14.
“They will save room and the labour of writing, and types may be easily formed for printing them. These are advantages not to be despised, when observations are to be noted once or oftener in the day.”
Three strokes, seven clouds
Howard names three simple modifications, two intermediate and two compound. Seven is no accident: it is every way of choosing one or more of the three strokes. The nimbus uses all three, and the book cannot settle on the order of its name: page 4 says cumulo-cirro-stratus, page 14 cirro-cumulo-stratus.
The pictures he gave up
His first edition came with plates of each cloud. Later he turned against them, in a bracketed note on that same page 14:
“I have now decided to omit these representations: being satisfied, both by reflection and experience, that the real student will acquire his knowledge in a more solid manner, by the observation of nature, without the aid of drawings, and that the more superficial are liable to be led into error by them.”
The 1865 edition prints that note and puts pictures back anyway, reproduced from his own watercolour sketches. Its editor added a footnote: “The author did not remain exclusively of this opinion”, citing Howard's later Seven Lectures on Meteorology and the dates of his notes on the sketches.
“Cumulostratus; as produced by the inosculation of cumulus with cirrostratus. Cirri above, passing to cirrocumulus.” Plate from the 1865 edition.
He was also candid about his Latin. In a footnote to his definitions, “stratus” is “a little forced”: the proper noun, stratum, did not end like the other two, and was already in use for a layer of cloud.
Sources: the Public Domain Review, “Luke Howard's Essay on the Modification of Clouds (1865)”, for Howard (1772–1864), his journals, the first systematic names and their meanings. Luke Howard, Essay on the Modifications of Clouds, third edition (London: John Churchill & Sons, 1865), Internet Archive bub_gb_7BbPAAAAMAAJ (a Google scan of the Indiana University copy): the seven definitions (pp. 3–4), the signs and the register rule (p. 14), the note on plates and the editor's footnote (pp. 14–15), the footnote on “stratus”, the preface on the illustrations, and the plate. The glyphs above are my redrawing of the printed signs; that seven is every non-empty choice of three is my arithmetic, not Howard's remark. Your register stays in this browser. Made by Claude, 3 October 2026.