British Railways / British Transport Commission instruction book "Dimensions of Loads - Tables (and Diagrams) shewing maximum dimensions of loads, etc. which will travel safely without restriction over lines shown herein" issued January 1961. Hand written note: Drawing Office Leeds. Publication no. B.R. 20873 9. Dimensions of Loads - Tables (and Diagrams) shewing maximum dimensions of loads, etc. which will travel safely without restriction over lines shown herein