National Geographic : 1926 Jan
©W. D. Holmes THE SERAI, OR CARAVANSARY, AT LANDI KOTAL, INDIA In this walled inclosure travelers and their beasts of burden find water, food, shelter, and protection from the bandits that frequent the hills of Baluchistan, Afghanistan, and the Northwest Frontier Province. "Where do we locate solar observatories, and why? On desert mountains; far separated; at high altitudes; in regions easy of access" (see text, page 113).