Linear moveout forms the basis for a simple, graphical method for finding seismic velocity. The method is particularly useful for the analysis of data that is no longer in a computer, but just exists on a piece of paper. Additionally, the method offers insights beyond those offered by the usual computerized hyperbola scan. Using it will help us rid ourselves of the notion that angles should be measured from the vertical ray. Non-zero Snell parameter can be the ``default.''
Ultimately this method leads to a definition of
a plane in which the layout of data,
after a linear invertible transformation,
shows the seismic velocity.