Soliton generation by a simple paddle mechanism. This demonstration is part of a graduate level nonlinear waves class at the Scripps Institution of Oceanography, where we study the KdV equation. Demos like this one (i.e. without breaking) clearly show the solitary structure of the wave form, and illustrate the soliton nature of the waves by looking at the interaction of two solitary waves (or equivalently the reflection off of a boundary - not shown).
Understanding the relationship between dispersion and nonlinearity is of central interest in this demo. As Whitham, and his student Seliger, showed, weakening the dispersion in the KdV equation (i.e. by describing full linear dispersion) allows for shock formation.

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