Petrology and cycles and the use of thermodynamic data and experiments in order to better understand the origins of rocks. There are three branches of petrology, corresponding to the three types of rocks: igneous, metamorphic, and sedimentary, and another dealing with experimental techniques: Petrology Petrology (from the Greek πέτρος, "pétros", "rock" and λόγος, "lógos", "subject matter", see -logy) is the branch of geology that studies rocks and the conditions under which they form. Petrology has three subdivisions: igneous, metamorphic, and sedimentary petrology. Igneous and metamorphic petrology are commonly taught together because they both contain heavy use of chemistry, chemical methods, and
What Is Spiritism? What Is Spiritism? What Is Spiritism? ("Qu'Est-ce Que le Spiritisme" in French) is a brief introduction to Spiritism written by Allan Kardec in 1859, which is about a quarter of the length of The Spirits Book. Modern editions are augmented by a brief biography of the author, written by Henri Sausse, in 1896 which is mostly focused on his role in the History of Spiritism. The book is structured as a series of conferences about Spiritism, intended to quench the public curiosity and dismiss false notions about the doctrine. It is not intended as an initiation and is not seen