If you have not yet found a reason for spending some time in London this summer, here is another one. London's Royal Academy is playing host to one of the finest collections of Impressionist paintings – by the likes of Monet, Manet, Renoir, Pissarro, Degas and Sisley – in the world.
Call it a stroke of luck if you like – or you might also say that one country's temporary loss is another's opportunity. The Sterling and Francine Clark Art Institute in Williamstown, Massachusetts is currently undergoing major refurbishment. For the first time in its history (it opened to the public in 1955), the core of its holdings of 19th-century French paintings is on loan to another institution, and London's Royal Academy is its beneficiary. Many of these paintings will be familiar to us but some of them will not be. We can see here, for example, a great work by the Barbizon School painter Théodore Rousseau called Farm in the Landes, purchased as recently as 2009, on which the painter worked obsessively for 25 years, and which has not been seen anywhere other than the Clark since it left the studio where it was painted.
Generally speaking, what we are appraising is not so much another group of Impressionist masterpieces as the taste of two collectors. Sterling Clark was an heir to the Singer sewing machine empire. He went to live in Paris in 1910 after a career in the military, and it was there that he met the French actress Francine Clary (born Francine Juliette Modzelewska, the daughter of a Parisian dressmaker) and picked up an appetite for collecting paintings and drawings.
Old Masters were his first love, but he soon discovered that French paintings could be acquired at much more modest prices. He acquired not only works by Impressionists, but paintings by those who had gone before them and had helped to shape their vision and their practice. He wanted to acquire works that would look good in a domestic situation, and the Impressionists seemed to fit. Their size was right – very few Impressionist paintings would not sit comfortably inside an average sitting room.
He was quite forward-looking for the time in which he was buying, keen to show an "advanced" interest in Renoir, for example, and to acquire works directly from Degas's atelier sales. Buying art enabled him to pursue an art education dictated by his own predilections, and to observe for himself how prices in the moderns were rising – which was, of course, a very good reason to gamble on the rising reputations of the artists.
Several of the rooms at the Royal Academy contain cabinets in which you can examine invoices from the dealers who were acquiring the works we can see. In 1923 he bought Manet's late Moss Roses in a Vase for $5,000. At 2010 prices, that would be the equivalent of $63,800 – the painting might be worth one hundred times as much if sold today.
Renoir became his greatest single passion – he eventually owned 39 of his works, 21 of which are at the Royal Academy. Yet he was also concerned to explore the lesser-known highways and byways, to learn for himself how one style evolved out of another, to examine how an artist such as Sisley changed as he aged and learnt from his fellow Impressionists (his palette became much richer and he developed an appetite for strong colour contrast). Clark bought the painters of the Barbizon school – Rousseau, Corot and others – and also works by painters of the Academy: Bouguereau and Gérome, for example.
His interest in the things that people do and how they live their lives is evident in a group of genre paintings in the show. He was a keen horseman and breeder of horses – he had an Epsom Derby winner in 1954 called Never Say Die – and this is reflected in Degas's painting Before the Race. Clark was as canny a horse dealer as he was as an art collector. Never Say Die and its rider could scarcely be more famous in horse racing. It was ridden by Lester Pigott, who was 18 years old that year; he went on to win that same race eight times more.
The show begins in still life, passes through landscape to portraiture, moves from genre paintings to studies of the female nude, and ends with self-portraits. Impressionists hang beside pre-Impressionists. In the first room, we see Renoir finding a remarkable degree of lift and luminosity in the reflective surface sheen of a lovely tumble of Onions, all casually arranged across a table cloth. This painting, so pleasingly modest in its subject matter, was said to be Sterling Clark's favourite Renoir of all, to be set above all those blowsy, saccharine women we can see elsewhere in his exhibition by the same artist.
Why do we it feel that it is so characteristically impressionist in its facture? Because of the extraordinary freedom and rushing vitality of its brush strokes. Lacking the stiff elaboration of Fantin-Latour's Roses in a Bowl and a Dish (1885), which stares across at it from the opposite wall, it seems to be capturing something on the wing, something that will go again just as surely as it has come.
Everywhere we look in this show we come across little surprises, new glimpses of an artist we think we know. One of these comes in a display of marine paintings. Here is an early Monet called Seascape: Storm, painted in 1866-67, seven long years before the first of the Impressionist exhibitions in Paris. You would never imagine that Monet could have painted such a dark and leaden scene, in which the paint looks as if it has been tamped into position with the aid of a palette knife. Compare this with Spring in Giverny, painted in 1890. This is as weightless, lively, lightsome and delicate as the other is foot-dragging and almost self-tortured.
From Paris: A Taste for Impressionism, Royal Academy, London W1 (020 7300 8000) 7 July to 23 September