The decan and term already recorded for this middle degree of Cancer trace to two named ancient writers. Vettius Valens, writing in Greek around the year 175, divided each sign into three ten degree faces under a rotating planetary sequence, leaving Mercury to rule this decan, the second of Cancer, and Ptolemy's Tetrabiblos separately preserves the Egyptian bounds table, keeping this degree under Mercury's own term as well, the two ancient divisions agreeing at the sign's midpoint. Neither writer pictured anything, only ruled it. The first complete pictorial set for all 360 degrees survives whole in 1494, in Johannes Angelus's Latin Astrolabium Planum, safely public domain but never freely translated into English. The next complete English set is Welsh minister John Thomas's, writing as Charubel in 1898, whose entry for this degree describes a pool of water given without further comment, a still, self contained image with no action taking place in or around it.
In practice, this degree is mostly used to time events through progressions or synastry. Practically, this degree is mostly used to time events through a progressed Sun, Moon or angle reaching it exactly, or to flag two charts sharing it closely enough to matter in synastry, both applications considerably younger than the decan and bound system carried underneath them.