"Great Western Railway Instructions" by William Wylie Grierson is a technical publication written in the early 20th century. This book serves as a set of detailed engineering instructions focused on railway construction and maintenance. Specifically, it addresses topics such as superelevation (or cant), expansion of rails, and the proper gauging and checking of curves to ensure the safe and efficient operation of train services. The content of the book is structured into clear sections that provide practical guidelines for railway engineers and workers. It outlines the necessary practices for managing superelevation in curves based on train speeds and gradients, explains how to account for thermal expansion in rail materials, and describes standards for laying gauge in different curve radii. Grierson emphasizes the importance of precision and safety in railway construction, offering examples and measurements to inform the engineering processes essential for the Great Western Railway's operations. The instructions not only reflect the technical needs of the time but also illustrate the importance of safety protocols in the burgeoning era of railway transportation. (This is an automatically generated summary.)