y following the
course of other arts. A vast amount of experimenting will be necessary
and artists and public alike must learn. But if it ever does develop to
the level of a fine art its only rival will be music, because the latter
is the only other abstract art. Material civilization has progressed far
and artificial light has been a powerful influence. May it not be true
that artificial light will be responsible for the development of
spiritual civilization to its highest level? If mobile light becomes a
fine art, it will be man's most abstract achievement in art and it may
be incomparably finer and more ethereal than music. If this is realized,
artificial light in every sense may well deserve to be known as the
torch of civilization.

READING REFERENCES

No attempt will be made to give a pretentious bibliography of the
literature pertaining to the various aspects of artificial lighting, for
there are many articles widely scattered through many journals. _The
Transactions of the Illuminating Engineering Society_ afford the most
fruitful source of further information; the _Illuminating Engineer_
(London), contains much of interest; and _Zeitschrift fuer
Beleuchtungswesen_ deals with lighting in Germany. H. R. D'Allemagne has
compiled an elaborate "Historie du Luminaire" which is profusely
illustrated, and L. von Benesch in his "Beleuchtungswesen" has presented
many elaborate charts. In both these volumes lighting devices and
fixtures from the early primitive ones to those of the nineteenth
century are illustrated. A few of the latest books on lighting, in the
English language, are "The Art of Illumination," by Bell; "Modern
Illuminants and Illuminating Engineering," by Gaster and Dow;
"Radiation, Light and Illumination," by Steinmetz; "The Lighting Art,"
by Luckiesh; "Illuminating Engineering Practice," consisting of a course
of lectures presented by various experts under the joint auspices of the
University of Pennsylvania and the Illuminating Engineering Society;
"Lectures on Illuminating Engineering," comprising a series of lectures
presented under the joint auspices of Johns Hopkins University and the
Illuminating Engineering Society; and "The Range of Electric Searchlight
Projectors," by Rey; "The Electric Arc," by Mrs. Ayrton; "Electric Arc
Lamps," by Zeidler and Lustgarten, and "The Electric Arc," by Child
treat the scientific and technical aspects of the arc. G. B. Barham has
furnished a book on "The