- Theory of governor operation. Page 14.
- Theory of governor operation. Page 13.
- Theory of governor operation. Page 12.
- Theory of governor operation. Page 11.
- Theory of governor operation. Page 10.
- Theory of governor operation.
- Theory of governor operation.
- The world standard diesel engine governor, circa 1950's.
- The Woodward Governor Company's Mill House plaque.
- The W.F. & John Barnes Company, Rockford, Illinois.
- THE VICTOR TURBINE CATALOGUE.
- The smallest and largest governor contraptions in the collection.
- THE ROCKFORD DRILLING MACHINE COMPANY.
- THE PELTON WATER WHEEL COMPANY.
- THE PELTON WATER WHEEL COMPANY AD FROM 1921.