¶To the splendid young folks, Sybil L. Almand, Florence M. Anthony, John N. Ogle, James W. Robinson, Stuart W. Jenks, and Thornton P. Dewhirst, who so efficiently assisted in the attainment of Photographs by Radio, Radio Vision, and Radio Photograms, this book, in grateful appreciation, is dedicated.
Mr. C. Francis Jenkins
Born in the country, north of Dayton, Ohio, in 1868, of Quaker parents. Spent boyhood on farm near Richmond, Indiana. Attended country school; a nearby high school; and Earlham College. “Explored” wheatfields and timber regions of Northwest, and cattle ranges and mining camps of Southwest United States. Came to Washington, D. C., in 1890, and served as secretary to Sumner I. Kimball, U. S. Life Saving Service. Resigned in 1895 to take up inventing as a profession. Built the prototype of the motion picture projector now in every picture theatre the world over; developed the spiral-wound paraffined all-paper container; and produced the first photographs by radio, and mechanism for viewing distant scenes by radio. Has over three hundred patents; and maintains a private laboratory in Washington. He is a member of the Franklin Institute, the American Association for the Advancement of Science, and founder of the Society of Motion Picture Engineers. Has several times been honored by scientific and other bodies for original research and attainment.
Foreword
The rapid development of apparatus for the transmission of photographs by wire and by radio may now be confidently expected, because the public is ready for it. At this very moment it is going through the same empirical process by which motion pictures arrived, and out of which finally the long film strip was born.
In the motion picture development there appeared the spiral picture disc; the picture “thumb book”; picture cards radially mounted on drums and bands; and the picture film continuously moved and intermittently illuminated.
But finally the development resolved itself into a single, long, transparent picture film, intermittently moved in the exposure aperture of the projecting machine; and upon this has been built one of the large industries of the world.
Doubtless this will be the history of the development of electrically transmitted photographs, and of radio vision, for many schemes have already been tried and more may yet be seen before the final, practical form shall have been evolved, and this new aid to business and to entertainment shall have taken its place in human affairs.
The transmission of a photograph electrically, a portrait, for example, is not so much a matter of mechanism, once the tools are perfected and their operation understood; it is more a matter of blending of line and tone, just exactly as it is with the artist. The great portrait photographer uses the same tools the amateur uses, but an acquired technique of high order enables him to produce a superior portrait, free of chalky contrasts, and soft in tone and blending. Just so in radio photography, it is a matter of simple mechanism, and an acquired skill in its use.
The author expects to see, very soon, the radio amateurs using flash-light lamps and electric pens where they now use headphones; and halftones or potassium cells where they now use microphones, for the radio problem between the two is practically the same—if anything rather more simple with light than with sound. And new means for modulating electric current by changing light values may be expected when the American boy starts to play with this new toy.