Vacuum Cleaning Systems
Reading edition
A Treatise on the Principles and Practice of Mechanical Cleaning
BY
M. S. COOLEY, M. E.
Mechanical Engineer in Office of the Supervising Architect, Treasury Department, Washington, D. C.
FIRST EDITION
New York: Heating and Ventilating Magazine Company, 1123 Broadway
Copyright, 1913, BY Heating and Ventilating Magazine Co.