Structure of the Earth decay of radioactive elements, and freezing of the inner core. Structure of the Earth The internal structure of the Earth is layered in spherical shells: an outer silicate solid crust, a highly viscous asthenosphere and mantle, a liquid outer core that is much less viscous than the mantle, and a solid inner core. Scientific understanding of the internal structure of the Earth is based on observations of topography and bathymetry, observations of rock in outcrop, samples brought to the surface from greater depths by volcanoes or volcanic activity, analysis of the seismic waves that pass through the Earth, measurements of
Science of Education: Its General Principles Deduced from its Aim and the Aesthetic Revelation of the World Science of Education: Its General Principles Deduced from its Aim and the Aesthetic Revelation of the World Science of Education (full title: Science of Education: Its General Principles Deduced from its Aim and the Aesthetic Revelation of the World) is a book written by the German empiricist Johann Friedrich Herbart. It was first published in German in 1806 and the first English printing was in 1902. Herbart emphasized education as the way for an individual to fulfill his potential and created a scientific method to help him do so. The Science of Education advocated a five-step methodology that appeals to