A convention of blobs

Stringham's letters from Kenya reported that he liked the place better than he had expected. They contained drawings of people met there, and of a horse he sometimes rode. He could not really draw at all, but used a convention of blobs and spidery lines effective in expressing the appearance of persons and things. One of these was of Buster selling a car; another of Buster playing polo.[...]
—Powell, A Question of Upbringing