The history of modern painting extends back about six hundred years. In the thirteenth century, the paintings which decorated some of the churches in Italy were painted in what is called a conventional way. That is to say, a certain custom was followed by all the painters. They represented the heads and hands of their figures, but the bodies were covered with draperies, under which there was little or no suggestion of any form or bulk. For the whole figure appeared flat. It was as if you should make a little figure of clay or paste, and then pass a roller over it, until its thickness is flattened down into nothing but length and breadth. The figures, in fact, gave no appearance of being real and lifelike because, as artists would say, there was no drawing in them. There was nothing to suggest that the figures had real bodies.