The Science of Living Things series demonstrates that Bobbie Kalman and her staff have turned out yet another informative and finely produced series of books. . . . this whole series would make a welcome addition to the elementary school library -- Kay Lehr, Fort Rouge School, Manitoba, Jan. 1999.
perpendicularity - the quality of being at right angles to a given line or plane (especially the plane of the horizon) oblongness, rectangularity - the property of being shaped like a rectangle.
Eccentricity(noun) the ratio of the distance between the center and the focus of an ellipse or hyperbola to its semi-transverse axis. Eccentricity(noun) the ratio of the distance of the center of the orbit of a heavenly body from the center of the body round which it revolves to the semi-transverse axis of the orbit. Eccentricity(noun) the distance of the center of figure of a body, as of an eccentric, from an axis about which it turns; the throw.