Isotropy and anisotropy: When a material is attacked by a liquid or vapor etchant, it is removed isotropically (uniformly in. all directions) or anisotropic etching (uniformity in vertical direction).
Some Questions Do Remain: 1  If the Earth was flat, we could travel to the place where the Earth and sky met. But we canât. 2  If the Earth was flat, we could reach the place where we could reach out and touch the Sun. But we canât. 3  If the Earth was flat, we could fall off the horizon. But we donâ 4 t. If the Earth was flat, it would simply fall.
The myth of the flat Earth is the modern misconception that the prevailing cosmological view during the Middle Ages in Europe was that the Earth is flat, instead of spherical. During the early Middle Ages, virtually all scholars maintained the spherical viewpoint first expressed by the Ancient Greeks.