Esch, Aleph-Sheen, 1.300, is the cosmic Fire. See Iysch and Esha
for its manifestation in man and woman. Esch is totally beyond our conception, with no existential-level letters like
Avir/Air and Mayim/Water. See The Three Mothers and
Chapter Three of the Sepher Yetsira for the transformations of
of Fire, Air and Water.