The train for Allahabad was to leave at eight P.M., and we were to spend the night in the railway carriage. We had ten reserved seats in a first-class carriage, and had made sure that no strange passengers would enter it, but, nevertheless, there were many reasons which made me think I could not sleep this night. So I obtained a provision of candles for my reading lamp, and making myself comfortable on my couch, began reading the pamphlet of Dr. Paul, which interested me greatly. Amongst many other interesting things, Dr. Paul explains very fully and learnedly the mystery of the periodical suspension of breathing, and some other seemingly impossible phenomena, practised by the Yogis. Here is his theory in brief. The Yogis have discovered the reason of the wondrous capacity of the chameleon to assume the appearance of plumpness or of leanness. This animal looks enormous when his lungs are filled with air, but in his normal condition he is quite insignificant. Many other reptiles as well acquire the possibility of swimming across large rivers quite easily by the same process. And the air that remains in their lungs, after the blood has been fully oxygenated, makes them extraordinarily lively on dry land and in the water. The capacity of storing up an extraordinary provision of air is a characteristic feature of all the animals that are subjected to hibernation. The Hindu Yogis studied this capacity, and perfected and developed it in themselves. The means by which they acquire it--known under the name of Bhastrika Kumbhala--consist of the following: The Yogi isolates himself in an underground cave, where the atmosphere is more uniform and more damp than on the surface of the earth: this causes the appetite to grow less. Man's appetite is proportionate to the quantity of carbonic acid he exhales in a certain period of time. The Yogis never use salt, and live entirely on milk, which they take only during the night. They move very slowly in order not to breathe too often. Movement increases the exhaled carbonic acid, and so the Yoga practice prescribes avoidance of movement. The quantity of exhaled carbonic acid is also increased by loud and lively talking: so the Yogis are taught to talk slowly and in subdued tones, and are even advised to take the vows of silence. Physical labor is propitious to the increase of carbonic acid, and mental to its decrease; accordingly the Yogi spends his life in contemplation and deep meditation. Padmasana and Siddhasana are the two methods by which a person is taught to breathe as little as possible. Suka-Devi, a well-known miracle-monger of the second century B.C. says: