A key purpose of this tree alphabet connects memory to time through the letters that define its yearly cycle. Each of its thirteen consonants corresponds to a 28 day sidereal, or lunar period that follow an anti-clockwise direction, while the five vowels follow a solar (sun-wise) direction to track solstice and equinox points. In addition, one hidden letter tracks the nineteen year metonic point when solar and lunar cycles re-calibrate (more on this lunar standstill event here).