Topography - Reality - Cognition [Voser
A) The solid and liquid earth bounded by the physical
earth's surface, or topographic surface, which
is the surface which we see, on which we stand, walk, drive, and, occasionally, swim. It is highly
irregular, even after some obvious smoothing which is always necessary to make it a smooth
surface amenable to mathematical treatment, and also after some averaging with respect to time
since this surface undergoes temporal variations (on the order of decimeter or more) because of
tidal effects, etc.