Audels Engineers and Mechanics Guide 6 is part of Frank D. Graham’s eight-volume reference series on modern engineering practice. First published in 1921, the series gave engineers, mechanics, students, and industrial workers a practical source of technical instruction.

Volume 6 focuses on boiler firing, oil burners, mechanical stokers, and equipment repairs. Its question-and-answer lessons explain combustion, fuel handling, furnace operation, boiler efficiency, maintenance, and methods for identifying mechanical problems.

Detailed illustrations help readers understand the internal construction of boilers and their supporting equipment. The diagram beside the title page depicts a vertical marine boiler, identifying features such as its furnace, tubes, heating surface, water level, steam outlet, and shell construction.

This volume is particularly relevant to the Steam Museum because it demonstrates how boiler operators once studied combustion, maintenance, and safe operation. It is preserved as part of the museum’s complete eight-volume Audels collection.