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.
RE: Perpendicularity. I am with J-P on this, the only basic dimension that applies for perpendicularity is basic 90 degrees to the datum and it is usually not shown on a print due to implied basic 90 deg dimension rule. dgallup, You said: The perpendicularity must be a refinement of the dimension tolerance, typically half or less..