around this time that he befriended the writer and poet Emile Verhaeren, whom he would later portray several times. In September 1883 van Rysselberghe went to Haarlem to study the light in the works of Frans Hals. The accurate rendering of light would continue to occupy his mind. There he also met the American painter William Merritt Chase. Les XX Théo van Rysselberghe was one of the prominent co-founders of the Belgian artistic circle Les XX on 28 October 1883. This was a circle of young radical artists, under the patronage, as secretary, of the Brussels jurist and art lover Octave Maus (1856–1919). They rebelled against the outmoded academism of the time and the prevailing artistic standards. Among the most notable members were James Ensor, Willy Finch, Fernand Khnopff, Félicien Rops, and later Auguste Rodin and Paul Signac. This membership brought van Rysselberghe in contact with other radical artists, such as James Abbott McNeill Whistler, who had exhibited in Les XX in 1884. His influence as a portrait painter can be seen in van Rysselberghe's portrait of Octave Maus as a dandy (1885). Van Rysselberghe would paint several portraits of Octave Maus and his wife between 1883 and 1890. Second trip to Morocco In November 1883 he left again, together with Frantz Charlet, for Tanger. During his stay of one year, he was in constant correspondence with Octave Maus, urging him to accept several new names for the first exhibition of "Les XX": Constantin Meunier, Alfred Verwee, William Merritt Chase. (He had met him in 1883 in Haarlem.) In April 1884 he visited Andalucia in the company of the American painter John Singer Sargent and the gentleman-painter Ralph Curtis. He also invited them to the exhibition in Brussels. This time, van Rysselberghe tried to surpass himself. His large, exotic painting Arabian phantasia, a theme introduced by Eugène Delacroix, is his best known work from this period. It is bathed in the harsh light of the hot Moroccan sun. From now on van Rysselberghe would be obsessed by light. But lack of funds forced him to return to Belgium at the end of October 1884. At the second show of Les XX in 1885 Théo van Rysselberghe showed his Arabian phantasia and other images and paintings from his second Moroccan trip, such as Abraham Sicsu (interpreter in Tanger) (1884). Impressionism Yet his next portraits are in rather subdued colours, using different