CHAPTER XXIV.

THE WESTINGHOUSE AIR-BRAKE 309

Invention of the Westinghouse Atmospheric Brake.--Distinct Classes of Inventions.--Benefits conferred on Train Men by Good Brakes.--First Trials of the Westinghouse Atmospheric Brake.--First Roads that Adopted the Westinghouse Brake.--Outlines of the Atmospheric Brake.-- How Eastern Railroads kept aloof from the Westinghouse Brake.--Lesson of the Revere Railroad Accident.--Weak Points of the Atmospheric Brake.--The Westinghouse Automatic Air-brake.--Life-saving Value of the Automatic Brake.--First Railroads that adopted the Westinghouse Automatic Air-brake.--Essential Parts of the Westinghouse Automatic Air-brake.--The Air-pump.--How the Air-pump Works.--How the Air-end Operates.--Air-pump Disorders.-- Puny Difficulties Vanquish the Ignorant Engineer.--Causes that make Brakes Inoperative often Easily Remedied.--Care of the Air-pump.--Pump Packing.--How Steam Passages get Choked.--Sagacity needed in Repairing Air-pumps.--Gradual Degeneration of the Air-pump.--Causes that make a Pump Pound.--The Triple Valve.--Action of the Triple Valve.-- To prevent creeping on of Brakes.--How to Apply and Release the Brake.