CHAPTER XVIII.

MOTOR BASED ON THE DIFFERENCE OF PHASE IN THE MAGNETIZATION OF THE INNER AND OUTER PARTS OF AN IRON CORE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

This chapter describes a motor that creates rotation by delaying the magnetic saturation of different layers of the iron core.

CHAPTER XIX.

ANOTHER TYPE OF TESLA INDUCTION MOTOR . . . . . . . . . . . . 92

CHAPTER XX.

COMBINATIONS OF SYNCHRONIZING MOTOR AND TORQUE MOTOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

A synchronizing motor runs at a fixed speed, while a torque motor provides high rotational force; Tesla combined these to create motors that could both start under a heavy load and then run at a steady speed.

CHAPTER XXI.

MOTOR WITH A CONDENSER IN THE ARMATURE CIRCUIT . . . 101

original: "Condenser." Now more commonly called a capacitor, this device stores electrical energy and was used here to adjust the timing of the electrical phases.

CHAPTER XXII.

MOTOR WITH CONDENSER IN ONE OF THE FIELD CIRCUITS . 106

CHAPTER XXIII.

TESLA POLYPHASE TRANSFORMER . . . . . . . . . . . . . . . . . . . . . 109

A polyphase transformer handles multiple alternating currents at once to change their voltage.

CHAPTER XXIV.

A CONSTANT CURRENT TRANSFORMER WITH MAGNETIC SHIELD BETWEEN COILS OF PRIMARY AND SECONDARY 113

A magnetic shield is a barrier used to control the magnetic interaction between the two parts of a transformer.

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PART II.

THE TESLA EFFECTS WITH HIGH FREQUENCY AND HIGH POTENTIAL CURRENTS.

original: "High Potential." This is a historical term for high voltage.

CHAPTER XXV.

INTRODUCTORY.—THE SCOPE OF THE TESLA LECTURES . . . . 119

CHAPTER XXVI.

THE NEW YORK LECTURE. EXPERIMENTS WITH ALTERNATING CURRENTS OF VERY HIGH FREQUENCY, AND THEIR APPLICATION TO METHODS OF ARTIFICIAL ILLUMINATION, MAY 20, 1891 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

original: "Alternate Currents." This landmark lecture at Columbia College introduced Tesla's work on high-frequency AC and his precursors to modern neon and fluorescent lighting.