o look back
through countless ages on our own evolution in previous manvantaras,
we should find that that which is now ourselves has passed on its
upward path through similar stages. That, however, is not the case
with the vast kingdom of nature-spirits; they neither have been, nor
ever will be, members of a humanity such as ours; their line of
evolution is entirely different, and their only connection with us
consists in our temporary occupancy of the same planet. Of course
since we are neighbours for the time being we owe neighbourly kindness
to one another when we happen to meet, but our lines of development
differ so widely that each can do but little for the other.

Many writers have included these spirits among the elementals, and
indeed they are the elementals (or perhaps, to speak more accurately,
the animals) of a higher evolution. Though much more highly developed
than our elemental essence, they have yet certain characteristics in
common with it; for example, they also are divided into seven great
classes, inhabiting respectively the same seven states of matter
already mentioned as permeated by the corresponding varieties of the
essence. Thus, to take those which are most readily comprehensible to
us, there are spirits of the earth, water, air, and fire (or
ether)--definite intelligent astral entities residing and functioning
in each of those media. It may be asked how it is possible for any
kind of creature to inhabit the solid substance of a rock, or of the
crust of the earth. The answer is that since the nature-spirits are
formed of astral matter, the substance of the rock is no hindrance to
their motion or their vision, and furthermore physical matter in its
solid state is their natural element--the only one to which they are
accustomed and in which they feel at home. The same is of course true
of those who live in water, air or ether. In mediaeval literature,
these earth-spirits are often called gnomes, while the water-spirits
are spoken of as undines, the air-spirits as sylphs, and the
ether-spirits as salamanders. In popular language they are known by
many names--fairies, pixies, elves, brownies, peris, djinns, trolls,
satyrs, fauns, kobolds, imps, goblins, good people, etc.--some of
these titles being applied only to one variety, and others
indiscriminately to all. Their forms are many and various, but most
frequently human in shape and somewhat diminutive in size. Like almost
all inhabitants of the