Illustration from 'The builder's jewel, or the youth's instructor, and workman's remembrancer' by Batty Langley (1696-1751), published in London in 1768. The full title of this work continues: 'explaining short and easy rules, made familiar to the meanest capacity for drawing and working; I. The five orders of columns entire, or any part of an order...II. Block and cantaliver cornices, rustick quoins, cornices proportioned to rooms...with a section of the Dome of St Paul's, London'.
© Science Museum / Science & Society Picture Library