This unprecedented reconstruction of Le Gray's work, on the initiative of the Bibliothèque Nationale de France (National Library of France), is the result of years of work in public and private collections around the world. It gives the measure of the capital contribution of this artist to the history of photography and therefore to the history of art in the 19th century. At the end of the 1840s, when photography was in its infancy, Gustave Le Gray intended to "unite science with art" and developed, among other procedures, the glass negative with collodion. Many students crowd his workshop, orders pour in… Next to official orders for French monuments (the Heliographic Mission, 1851) and then for the Emperor Napoleon III (the Châlons-sur-Marne camp, 1857), Le Gray creates a personal work, in the Fontainebleau forest, by the sea, from Cherbourg to Sète, in the heart of Paris: so many series whose artistic requirement - which is now imposed on everyone - marginalizes this photographer as too little "commercial" for its time ... Fleeing its creditors, Le Gray left Paris in May 1860 for a cruise in the East, aboard the Emma, ​​the schooner of Alexandre Dumas. After an improvised stopover in Palermo where, in the midst of a Garibaldian insurrection, he immortalized heroes, ruins and barricades, he reached Syria and then Egypt. His photographs are dazzling with technical mastery, balance, fine detail and chromatic richness. Nourished by pictorial references, they recall Paul Delaroche, Caspar David Friedrich, Raffet, Ingres, romantic lithographs, history painting, but they also prefigure new themes - which we will emerge under the brush of Monet or Courbet. Please note that the book is written in the French language.The book is published by Gallimard and is in good condition