It is the primary aim of this book to present authentic data of such scope as to be useful to the chemist, physicist, engineer, biologist, ophthalmologist and physician and others interested in ultraviolet radiation. Theory has been subordinated to experimental facts because the latter are not affected by the inevitable changes in theory. Much of the literature on this subject is confusing because of the lack of care in the choice of definitions and of limited value resulting from carelessness in specifying important factors. From this mass of isolated material the author has coördinated much valuable data. The many references which are included increase the usefulness of the book. LIGHTING THE HOME 5 x 7-1/2, illustrated, 289 pages $2.00 This is a pioneer book. It ranks with books on interior decoration and furniture as a help toward transforming a house into a home. It is practical in that it offers advice on all sorts of lighting problems and it is fascinating reading as well. ARTIFICIAL LIGHT, ITS INFLUENCE ON CIVILIZATION 6 x 9, illustrated, 366 pages $3.00 This story of the achievements of artificial light is written especially for the man in the street who is not interested in technical scientific terms and formulae, but who looks with admiration upon the huge signs which flash and sparkle above the crowds on the Great White Way, who marvels at the colors and brilliance of a spectacular theatrical production and desires to know how it is accomplished, and who takes a natural delight in hearing about scientific discoveries when they are explained in the simple, vivid language he understands best. THE LIGHTING ART, ITS PRACTICE AND POSSIBILITIES 6 x 9, illustrated, 229 pages $2.50 This book discusses lighting as engineering plus art, and treats the subject as a branch of interior and exterior decoration. The technical aspect of the subject is not neglected, but the main emphasis is upon the "why" and not merely the "how" of lighting. THE LANGUAGE OF COLOR 6 x 9, illustrated, 282 pages $2.00 A practical volume on color, the various fields in which it is used and its importance in portraying the ideas that make for progress. A book of special interest to all those who deal in color schemes and values. THE BOOK OF THE SKY 6 x 9, illustrated, 236 pages $3.50 "The beauties, wonders, awesome spectacles, inspiring panoramas, and extensive ranges of vision which await the aerial traveler, make of cloudland a veritable fairyland if he will open his consciousness to them. Aircraft have brought this new world of experiences within easy reach of mankind and it is one of the aims of this volume to awaken those who fly, or would fly, to the variety of interest which air travel affords." _The_ Literature of Engineering and the Industries