urse of civilization has been highly complex
and cannot be symbolized adequately by the branching tree. From its
obscure beginning far in the impenetrable fog of prehistoric times, it
has branched here and there. These various branches have been subjected
to many different influences, with the result that some flourished and
endured, some retrogressed, some died, some went to seed and fell to
take root and to begin again the upward climb. The ultimate result is
the varied civilization of the present time, a study of which aids in
penetrating the veil that obscures the ages of unrecorded writing.
Likewise, material relics of bygone ages supply some threads of the
story of human progress and mythology aids in spanning the misty gap
between the earliest ages of man and the period when historic writings
were begun. Throughout these various stages it becomes manifest that the
development of artificial light is associated with the progress of
mankind.

According to a certain myth, Prometheus stole fire from heaven and
brought this blessing to earth. Throughout the mythologies of various
races, fire and, as a consequence, light have been associated with
divinity. They have been subjects of worship perhaps more generally than
anything else, and these early impressions have survived in the
ceremonial uses of light and fire even to the present time. The origin
of fire as represented in any of the myths of the superstitious beings
of early ages is as suitable as any other, inasmuch as definite
knowledge is unavailable. Active volcanoes, spontaneous combustion,
friction, accidental focusing of the sun's image, and other means may
have introduced primitive beings to fire. A study of savage tribes of
the present age combined with a survey of past history of mythology, of
material relics, and of the absence of lamps or other lighting utensils
leads to the conclusion that the earliest source of light was the wood
fire.

[Illustration: PRIMITIVE FIRE-BASKETS]

[Illustration: CRUDE SPLINTER-HOLDERS]

[Illustration: EARLY OPEN-FLAME OIL AND GREASE LAMPS]

Even to-day the savages of remote lands have not advanced further than
the wood-fire stage, and they may be found kneeling upon the ground
energetically but skilfully rubbing sticks together until the friction
kindles a fire. In using these fire-sticks they convert mechanical
energy into heat energy. This is a fundamental principle of physics,
employed by them as necessity demands,