Figure 3. (a) Maximum wave profiles with crest at center for 3.32 Hz forcing in physical experiments. The five forcing amplitudes are 2.65 mm, 2.87 mm, 3.17 mm, 3.49 mm and 3.87 mm. (b) Forcing frequency is 3.20 Hz, forcing amplitudes are 1.61 mm, 1.92 mm, 3.17 mm, 3.49 mm and 3.88 mm. Wave amplitude increases with forcing amplitude. The vertical scale is twice as large as the horizontal scale.