"I am reading with much interest your remarkable book. I am deeply interested and profited by its study. It is grand, cheering, helpful."--_Rev. Dr. R. S. MacArthur._ "Your book has impressed me very greatly for its learning, research and intellectual force."--_Gen. John W. Noble_ (_Ex-Secretary of the Interior._) "Its arguments are carefully worked up on scientific lines and it is interesting reading from cover to cover."--_New York Tribune._ "Few writers have ventured such boldly frank opinions. His style is polished and sometimes brilliant, while his thoughts are presented with lucid directness."--_N. Y. Evening Telegram._ "It is a fascinating work which goes intelligently and with scientific plausibility into speculations concerning the destinies of Men and the Universe."--_The New York World._ "So much has been accomplished by electricity in the last few years that no person can come forward and say with reason that the electric theory of Col. Warder is not correct."--_Denver Republican._ "Your books are intensely interesting and instructive. I accept their theories and believe they will finally prevail and revolutionize scientific thought. Have read them three times."--_Dr. L. M. Taylor_ (_Scientist, Washington, D. C._). "I know no greater favor that I can bestow on my friends than to present them your book, 'The Cities of the Sun.' It will give them new thoughts and teach them to think. Send me fifty volumes to-morrow."--_Col. Henry H. Adams, 177 Broadway, New York._ 12mo. Cloth Bound, $1.50 WHAT IS SAID OF INVISIBLE LIGHT By GEORGE WOODWARD WARDER "Col. Warder's book has attracted gratifying attention among literary and scientific people. His theory of electrical creation has been fully discussed and approved by many scientific men, and his new publication, 'Invisible Light,' will give the critics and scientists something new to puzzle over."--_The Kansas City World._ "Perhaps no writer on a scientific subject has quite equaled Col. Warder in boldness of treatment, and characteristic imagery of presentment. He repudiates the law of gravity, and adopts electricity as the evolving force in Creation, and proclaims the sun to be inhabited."--_The Kansas City Journal._ "If he fails to break up the existing scientific theories it will not be his fault. We have read his work with interest, and whatever the opinion of scientific critics the fact remains that it contains ample and original food for thought."--_Atlanta Constitution._ "He claims electricity is the medium and agency of Creative power in the evolution of the universe. That the sun is inhabitable, and the spiritual center and promised heaven of the Solar System. The reader will be forced to admit that he furnishes good proof for all his assertions."--_The Kansas City Mail._