The art exhibition has played a crucial part in the market for new art since the 18th and 19th centuries. The Paris Salon, open to the public from 1737, rapidly became the key factor in determining the reputation, and so the price, of the French artists of the day. The Royal Academy in London, beginning in 1769, soon established a similar grip on the market, and in both countries artists put great efforts into making pictures that would be a success, often changing the direction of their style to meet popular or critical taste. The British Institution was added to the London scene in 1805, holding two annual exhibitions, one of new British art for sale, and one of loans from the collections of its aristocratic patrons. These exhibitions received lengthy and detailed reviews in the press, which were the main vehicle for the art criticism of the day. Critics as distinguished as Denis Diderot and John Ruskin held their readers attention by sharply divergent reviews of different works, praising some extravagantly and giving others the most savage put-downs they could think of. Many of the works were already sold, but success at these exhibitions was a crucial way for an artist to attract more commissions. Among important early one-off loan exhibitions of older paintings were the Art Treasures Exhibition, Manchester 1857, and the Exhibition of National Portraits in London, at what is now the Victoria and Albert Museum, held in three stages in 1866-68.