Examples from literature

• In the figure it will be noticed that the rising portion of the curve is somewhat steep, and the recovery convex to the abscissa, the fall being relatively rapid in its first, and less rapid in its later, parts. 
• In this cause-and-effect curve, the first part is slightly convex to the abscissa, the second straight and ascending, and the third concave. 
• The curve as a whole becomes, first slightly convex to the abscissa, then straight and ascending, and lastly concave. 
• The ordinate in these curves represents the E.M. variation, and the abscissa the time. 
• To provide for such cases the curve is drawn as if it never touched the abscissa.