Tangent. A line drawn from a circle at an angle, instead of radially. Technically. Pertaining to some particular trade, science or art. Tenuous. Thin, slender, willowy, slight. Tetrahedral. This has reference to a form which is made up of a multiplicity of triangularly shaped thin blades, so as to form numerous cells, and thus make a large number of supporting surfaces. Used as a kite. Theories. Views based upon certain consideration. Theoretical. Where opinions are founded on certain information, and expressed, not from the standpoint of actual knowledge, but upon conclusions derived from such examinations. Torsion. A twist; a circular motion around a body. Transmitted. Sent out; conveyed from one point to another. Transformed. Changed; entirely made over from one thing to another. Transverse. When a body is shorter from front to rear than from side to side its longest dimension is transversely. Distinguish from lateral, which has reference only to the distance at right angles from the main body. Translation. The transportation of a body through the air. Trajectory. The path made by a body projected through the air. Triangular. A form or body having three sides and three angles. Typical. In the form of; a likeness to. Ultimate. The end; the finality; the last that can be said. Uninitiated. Not having full knowledge; withont information. Unique. Peculiar; something that on account of its peculiar construction or arrangements stands out beyond the others. Universal. Everywhere; all over the world. Undulate. To move up and down; a wave-like motion. Utility. Of use; to take advantageous use of. Unstable. Not having anything permanent; in a ship in flight one that will not ride on an even keel, and is liable to pitch about. Vacuum. Where air is partly taken away, or rendered rarer. Valved. A surface which has a multiplicity of openings with valves therein, or, through which air can move in one direction. Vaunted. To boast concerning; to give a high opinion. Velocity. Speed; the rate at which an object can move from place to place. Vertical. A line running directly to the center of the earth; a line at right angles to the surface of water. Vibratory. Moving from side to side; a regular motion. Volplane. The glide of a machine without the use of power. Warping. The twist given to certain portions of planes, so as to cause the air to aet against the warped portions. Weight. The measure of the force which gravity exerts on all objects.