If we hit the bathymetry, set the location to where we came from.

def __reverse(self, **kwargs):
        """
            If we hit the bathymetry, set the location to where we came from.
        """
        start_point = kwargs.pop('start_point')
        return Location4D(latitude=start_point.latitude, longitude=start_point.longitude, depth=start_point.depth)