Some reading material from the early 20th century, but mind some are large PDF files! **LINK**
A PRACTICAL TREATISE ON LOCOMOTIVE BOILER AND ENGINE
DESIGN, CONSTRUCTION, AND OPERATION
BY
LLEWELLYN V. LUDY, M.E.
PROFESSOR OF EXPERIMENTAL ENGINEERING, PURDUE
UNIVERSITY
AMERICAN SOCIETY OF MECHANICAL ENGINEERS
ILLUSTRATED
AMERICAN TECHNICAL SOCIETY
CHICAGO
1920
**LINK** main directory
BR test performance and efficiency test WR Hall class 1951
Cyril