Mr. Whistler always spelt art, and we believe still spells it, with a capital I.
Source: The New President, in Pall Mall Gazette (London, 26 Jan. 1889; repr. in Aristotle at Afternoon Tea: The Rare Oscar Wilde, 1991).
-- Oscar Wilde, (Oct 16 1856-1900), Anglo-Irish playwright, novelist; He was noted for his flamboyant witty, sophisticated plays, e.g., The Importance of Being Ernest, 1895.