 Great use was made of the new ability to print large graphic illustrations on the same pages as the text, as opposed to limiting illustrations to separate copperplates.Although this technology had first been used in a primitive fashion the 7th edition, and to a much lesser extent in the 8th, in the 9th edition there were thousands of quality illustrations set into the text pages, in addition to the plates.The 9th edition was a critical success, and roughly 8,500 sets were sold in Britain.