has been assigned to me--that of preparing the
present edition--by reason of the fact that it was in my presence and at my
instigation that the first efforts were made to penetrate the mystery
previously enshrouding the ultimate molecule of matter.

I remember the occasion vividly. Mr. Leadbeater was then staying at my
house, and his clairvoyant faculties were frequently exercised for the
benefit of myself, my wife and the theosophical friends around us. I had
discovered that these faculties, exercised in the appropriate direction,
were ultra-microscopic in their power. It occurred to me once to ask Mr.
Leadbeater if he thought he could actually _see_ a molecule of physical
matter. He was quite willing to try, and I suggested a molecule of gold as
one which he might try to observe. He made the appropriate effort, and
emerged from it saying the molecule in question was far too elaborate a
structure to be described. It evidently consisted of an enormous number of
some smaller atoms, quite too many to count; quite too complicated in their
arrangement to be comprehended. It struck me at once that this might be due
to the fact that gold was a heavy metal of high atomic weight, and that
observation might be more successful if directed to a body of low atomic
weight, so I suggested an atom of hydrogen as possibly more manageable. Mr.
Leadbeater accepted the suggestion and tried again. This time he found the
atom of hydrogen to be far simpler than the other, so that the minor atoms
constituting the hydrogen atom were countable. They were arranged on a
definite plan, which will be rendered intelligible by diagrams later on,
and were eighteen in number.

We little realized at the moment the enormous significance of this
discovery, made in the year 1895, long before the discovery of radium
enabled physicists of the ordinary type to improve their acquaintance with
the "electron." Whatever name is given to that minute body it is recognised
now by ordinary science as well as by occult observation, as the
fundamental unit of physical matter. To that extent ordinary science has
overtaken the occult research I am dealing with, but that research rapidly
carried the occult student into regions of knowledge whither, it is
perfectly certain, the ordinary physicist must follow him at no distant
date.

The research once started in the way I have described was seen to be
intensely interesting. Mrs. Besant almost immediately co-operated with M