\Hy*drog"ra*phy\, n. [Hydro-, 1 + -graphy: cf. F.
hydrographie.]
1. The art of measuring and describing the sea, lakes,
   rivers, and other waters, with their phenomena.

2. That branch of surveying which embraces the determination
   of the contour of the bottom of a harbor or other sheet of
   water, the depth of soundings, the position of channels
   and shoals, with the construction of charts exhibiting
   these particulars.