Late nineteenth-century hypothesis suggested by physicists
as a means of accounting for the propagation of light as a wave
motion through otherwise empty space. The idea of ether meshed
with the teachings of the mesmerists and Theosophists,
who spoke of subtle substructures of matter sometimes referred
to as koilonall-pervading, filling all space, and interpenetrating
all matter. Ether was supposedly of very great density,
10,000 times more dense than water and with a pressure of 750
tons per square inch.
According to Theosophical teaching, ether was said to be capable
of being perceived only by clairvoyants with the most
highly developed powers. It was said to be filled with an infinitude
of small bubbles, much like the air bubbles in treacle or
some other viscid substance. The bubbles were supposedly
formed at some ancient time by the infusion of the breath of
the Logos into the ether. Of these bubblesnot of the ether
matter was said to be built, its density varying with the number
of bubbles combined to form each objects.
Ether became the subject of one of the more famous experiments
in physics, by Albert Abraham Michelson and E. W. Morley.
Their experiment involved the splitting and reintegration
of a light wave in such a manner that the presence of ether
would slow one of the waves. They disproved the existence of
ether and brought America its first Nobel Prize for physics. The
experiment also contributed to the development of Einsteins
theory of relativity. The abandonment of ether by science led
to its eventual abandonment by Spiritualists and Theosophists.