He was a writer on art and an art dealer.
He was dealer for the Independent Gallery; as Samuel Courtauld's principal adviser, he was central in the acquisition of many of his paintings. His books include monographs on Millet, [1910], Van Dyck, [1908], Stories of the French Artists from Clouet to Delacroix, (with Charles Henry Collins Baker, London, 1909); and The Appreciation of Painting, London,1921.
The Frick Collection Research website.
Online books Library website.