A practical handbook of British birds, London, Witherby, 1920-24, birds, Great Britain., The illustration provides a series of diagrams demonstrating various techniques for measuring different anatomical features of birds. The top section depicts how to measure the wings, highlighting the use of a ruler for precise length measurements from the base to the tip. Following this, another diagram illustrates the method for measuring the tarsus, showcasing the placement of a measuring tape to ensure accuracy from the joint to the tip. Additionally, there is a depiction of the method for measuring the bill, detailing how to measure from the base of the bill to the tip. Each method emphasizes careful measurement for scientific study and documentation.