Constable: Skying review – 40 cloud studies that show a painter learning to look up

In the summers of 1821 and 1822, John Constable went up to Hampstead Heath most afternoons with a box of oil paints and a stack of paper and painted the sky. He called it “skying”. He noted the date, the time and the wind on the back of each one, and the studies, most of them finished in an hour, were never intended for exhibition. Bristol Museum and Art Gallery has gathered 40 of them, from public and private collections, and hung them in a single room, and for about half an hour it is one of the most absorbing exhibitions in the country.

What the studies show is a painter teaching himself to see something that would not hold still. The early ones, from 1821, are slightly anxious: the cloud is rendered as an object, a thing with edges. By the end of the following summer, the edges have gone, and what is on the paper is weather, the sense of a mass of vapour that was somewhere else a minute ago. A study dated 5 September 1822, “looking SE, noon, wind very brisk”, with a cumulus top blown into a ragged anvil, is as good a piece of observational painting as exists in English art, and it is 24cm wide.

The exhibition’s curator, Robert Lanyon, has hung the studies chronologically and at eye level, with the inscriptions reproduced beside them, which is exactly right. The room is small, the walls are a dark grey, and the effect is of standing in a quiet place while a great deal happens overhead. There is a single large finished painting at the far end, a view of the heath on loan from a London collection, and it is instructive to walk back to the studies from it: the finished sky is magnificent, and it is also, by comparison, a performance.

The difficulty is the second room, in which the museum has commissioned six contemporary artists to respond to the studies. The intention is generous and some of the work is fine, a series of timed photographs of the sky above Bristol’s Clifton Down over a single day has a real affinity with what Constable was doing, but a large video installation involving a weather balloon is both noisy and beside the point, and the room as a whole pulls attention from the thing it is meant to honour. The studies needed nothing. They did not need this.

There is also a missed opportunity in the interpretation. The exhibition mentions, but does not pursue, the fact that Constable was reading contemporary meteorology at the time and that the classification of clouds into cumulus, stratus and cirrus was then barely 20 years old. A painter who was learning the new science as he painted is a richer story than the exhibition quite tells.

But go for the first room. Stand in front of 5 September 1822 for as long as the gallery will let you.

Constable: Skying is at Bristol Museum and Art Gallery until 18 January.