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Zustand: Like New. Newton, Mr David; Loyd, Ms Katie (illustrator). Most items will be dispatched the same or the next working day. An apparently unread copy in perfect condition. Dust cover is intact with no nicks or tears. Spine has no signs of creasing. Pages are clean and not marred by notes or folds of any kind.

Paperback. Zustand: Brand New. Loyd, Ms Katie (illustrator). 199 pages. 9.00x6.00x0.45 inches. In Stock.

Paperback. Zustand: Brand New. Loyd, Ms Katie (illustrator). 186 pages. 9.00x6.00x0.42 inches. In Stock.

Zustand: New. In.

Zustand: Very Good. bon etat. Sans date. Very Good.

Softcover. Ex-library with stamp and library-signature. GOOD condition, some traces of use. Ancien Exemplaire de bibliothèque avec signature et cachet. BON état, quelques traces d'usure. Ehem. Bibliotheksexemplar mit Signatur und Stempel. GUTER Zustand, ein paar Gebrauchsspuren. 47 GIR 9781470426651 Sprache: Französisch Gewicht in Gramm: 550.

(Paris, Gauthier-Villars), 1880. 4to. No wrappers. In: "Comptes Rendus Hebdomadaires des Séances de L'Academie des Sciences", Tome 91, No 18. Pp.(698-) 736. (Entire issue offered). Bell's paper: pp. 726-727. First printing of the paper in which Bell speculates how his and Tainter's invention of the Photophone or Radiophone could have a wider use. He pondered the photophone's possible scientific use in the spectral analysis of artificial light sources, stars and sunspots. He later also speculated on its possible future applications, though he did not anticipate either the laser or fiber-optic telecommunications:"Can Imagination picture what the future of this invention is to be! We may talk by light to any visible distance without any conduction wire. In general science, discoveries will be make by the Photophone that are undreamed of just now." Not long after its invention laboratories within the Bell System continued to improve the photophone in the hope that it could supplement or replace expensive conventional telephone lines. Its earliest non-experimental use came with military communication systems during World War I and II, its key advantage being that its light-based transmissions could not be intercepted by the enemy.