He contributed sketches to the "Illustrated London News", signing them as Frank Leslie to insure his anonymity. These were so cordially welcomed that he eventually gave up commerce and was made superintendent of engraving on that journal. He made himself an expert and inventor in his new work. It was here that he learned the operation known as overlaying – the system of regulating light and shade effects – in pictorial printing, a system which he was the first to introduce to the United States.