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.

CHAPTER XXV.

THE EAMES VACUUM BRAKE 341

Efficiency of the Brake on the Elevated Railroads.--
Operation of the Brake.--The Diaphragm.--The Ejector.--
Care of the Brake.

CHAPTER XXVI.

POWER OF LOCOMOTIVES AND TRAIN RESISTANCES 346

Calculating Power of Locomotives.--Proportion of Adhesion
to Traction.--Estimating Tractive Power.--Horse-power of
Locomotives.--Formulas of Train Resistances.--Experiments
of Train Resistances on the Erie Railway.--Conditions that
Increase Train Resistances.--Resistance of Curves.--Work
done by a Locomotive pulling a Train.--Record of Fast
Express Train made by Professor P. H. Dudley’s Dynagraph
Car.--Calculations of Weight of Trains that Locomotives
can Pull.

CHAPTER XXVII.

WATER FOR LOCOMOTIVE BOILERS 359

How Water gets mixed with Lime.--Expense entailed by
using Bad Water.--Efforts of Master Mechanics to secure
Good Water.--Loss of Faith in Purifying Methods.--
Scale-making Agencies.--To Ascertain the Quality of
Water.--Appliances needed in Testing Water.--Preparing
for the Experiments.--Lime held in Solution by Free
Carbonic Acid.--Test for Lime Salts.--Test for Sulphate
of Lime.--Test for Carbonate of Magnesia.--Test for Salts
of Iron.--Test for Chlorine.--Learning the Manipulation
of Tests.--Making Qualitative Tests.--The Soap-test for
Hardness.--Modification of the Clark Soap-test.--Applying
the Soap-test.--Difficulties of purifying Water for
Locomotives.--Mud.--Carbonate of Lime.

CHAPTER XXVIII.

EXAMINATION FOR LOCOMOTIVE ENGINEERS 376

Principal Duties of an Engineer.--Carrying Water
in Boiler.--Procedure when Short of Water.--
Boiler-foaming.--Disconnecting the Engine.--Slipping an
Eccentric.--Breaking a Valve-yoke.--Cylinder-packing
Blowing.--Broken Rocker-arm.--Broken Link-hanger.--
Broken Side Rods.--Throttle Disconnected.--Broken Tires.

LOCOMOTIVE ENGINE RUNNING.