The full title of the book is “The theory of perspective demonstrated; in a method entirely new by which the several planes, lines and points, made use of in this art, are shewn in the true positions in which they are to be considered ”. It consists two bands, text and graphic band. The text band is divided into four sections. The first two sections about the doctrine of planes applied to the true principles of perspective. The third section is about the conclusion and in the fourth section the comments are gathered. In the graphic band the illustrations are used to demonstrate the principles of perspective. What is special is that the author has used different coloured threads through the paper to demonstrate this principle in a three-dimensional way. The first band is about 2 cm thick and smaller than A4 paper. This graphic band may be the same size as the text band of the book, a little smaller than a4. This means that one can clearly see the illustrations and check the cases showed in the graphic and at the same time can take them easily. This book is written by John Lodge Cowley, who was a professor of mathematics at the Royal Military Academy, Woolwich, London, for a number of years between 1761 and 1773. He was famous of his mathematical methods and at the same time was an important geographer as well as Cartographer Royal to King George II. He specialised in maps that depicted the counties of the United Kingdom from which arose his most famous work, Counties of England.