Simon Callow said this quote

“ He very soon acquired the reputation of being the best public speaker of his time. He had taken pains to master the art, approaching it with scientific precision. On the morning of a day on which he was giving a speech, he once told Wilkie Collins, he would take a long walk during which he would establish the various headings to be dealt with. Then, in his mind’s eye, he would arrange them as on a cart wheel, with himself as the hub and each heading a spoke. As he dealt with a subject, the relevant imaginary spoke would drop out. When there were no more spokes, the speech was at an end. Close observers of Dickens noticed that while he was speaking he would make a quick action of the finger at the end of each topic, as if he were knocking the spoke away. ”