Part 7

=CURVE.=--A line of which no part is straight.

Reversed Curve.--One whose curvature is first in one direction and then in the opposite direction.

Spiral Curve.--A plain curve which winds about and recedes, according to some law, from its point of beginning, which is called its center.

=CYLINDER.=--A solid bounded by a curved surface and by two opposite faces called bases; the bases may be any curved figures and give the name to the cylinder; thus a circular cylinder is one whose bases are circles.

=CYLINDRICAL.=--Having the general form of a cylinder.

=DEGREE.=--The 360th part of a circle.

=DESCRIBE.=--To make or draw a curved line; to draw a plan.

=DESIGN.=--Any arrangement or combination to produce desired results in industry or art. To delineate a form or figure by drawing the outline--a sketch.

=DEVELOP.=--To unroll or lay out.

=DIAGONAL.=--A right line drawn from angle to angle of a quadrilateral or many angled figure and dividing it into two parts.

=DIAMETER.=--A right line passing through the center of a circle or other round figure terminated by the curve and dividing the figure symmetrically into two equal parts.

=EDGE.=--The intersection of any two surfaces.

=ELEVATION.=--The term elevation, vertical projection and front view--applied to drawings--all have the same meaning.

=FACE.=--One of the plane surfaces of a solid; it may be bounded by straight or curved edges.

=FINISHING.=--Completing a drawing whose lines have been determined by erasing unnecessary lines and strengthening and accentuating where this is needed.

=FORESHORTENING.=--Apparent decrease in length, owing to objects being viewed obliquely; thus a wheel, when seen obliquely, instead of appearing round, presents the appearance of an ellipse.

=FREE-HAND.=--Executed by the hand unaided by instruments.

=GENERATED.=--Produced by.

=GEOMETRIC.=--According to geometry.

=HALF-TINT.=--The shading produced by means of parallel equidistant lines.

=HEMISPHERE.=--Half a sphere obtained by bisecting a sphere by a plane.

=HORIZONTAL.=--Parallel to the surface of smooth water. In drawing, a line drawn parallel to the top and bottom of the sheet is called horizontal.

=INSCRIBE.=--See circumscribe--its opposite.

=INSTRUMENTAL.=--By the use of instruments.

=LINE.=--A line has length, only, as A C; a right line is a straight line, the shortest line that can be drawn between two points, A----C.

Straight. One which has the same direction throughout its entire length.

Curved. One no part of which is straight.

Broken. One composed of different successive straight lines.