Swami Vivekananda. Raja-Yoga. Preface Introductory The First Steps Prana The Psychic Prana The Control of the Psychic Prana Pratyahara and Dharana Dhyana and Samadhi Raja-Yoga in Brief Patanjali's Yoga Aphorisms IntroductionConcentration: Its Spiritual UsesConcentration: Its PracticePowersIndependenceAppendix - References To Yoga