André Authier is Professor Emeritus at the Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Université P. et M. Curie in Paris. He was Full Professor at Paris University and former president of the International Union of Crystallography.

• 1. Significance of the discovery of X-ray diffraction ; 2. The various approaches to the concept of space lattice ; 3. The dual nature of light ; 4. Rontgen and the discovery of X-rays ; 5. The nature of X-rays: waves or corpuscles? ; 6. The discovery of X-ray diffraction and the birth of X-ray analysis ; 7. The first steps ; 8. The route to crystal structure determination ; 9. X-rays as a branch of optics ; 10. Early applications of X-ray crystallography ; 11. Unravelling the mystery of crystals - the forerunners ; 12. The birth and rise of the space-lattice concept

Readers of the Early Days of X-ray Crystallography from both camps will be rewarded by a thoroughly researched account on the multiple faces of a scientific specialty. Historians of science will find here a rich source for further study. Crystallographers will appreciate the lesson that the historical roots of their discipline are more ramified than it may appear from a mere rational reconstruction of ideas and concepts.

André Authier is Professor Emeritus at the Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Université P. et M. Curie in Paris. He was Full Professor at Paris University and former president of the International Union of Crystallography.

• 1. Significance of the discovery of X-ray diffraction ; 2. The various approaches to the concept of space lattice ; 3. The dual nature of light ; 4. Rontgen and the discovery of X-rays ; 5. The nature of X-rays: waves or corpuscles? ; 6. The discovery of X-ray diffraction and the birth of X-ray analysis ; 7. The first steps ; 8. The route to crystal structure determination ; 9. X-rays as a branch of optics ; 10. Early applications of X-ray crystallography ; 11. Unravelling the mystery of crystals - the forerunners ; 12. The birth and rise of the space-lattice concept

Readers of the Early Days of X-ray Crystallography from both camps will be rewarded by a thoroughly researched account on the multiple faces of a scientific specialty. Historians of science will find here a rich source for further study. Crystallographers will appreciate the lesson that the historical roots of their discipline are more ramified than it may appear from a mere rational reconstruction of ideas and concepts.

André Authier is Professor Emeritus at the Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Université P. et M. Curie in Paris. He was Full Professor at Paris University and former president of the International Union of Crystallography.

• 1. Significance of the discovery of X-ray diffraction ; 2. The various approaches to the concept of space lattice ; 3. The dual nature of light ; 4. Rontgen and the discovery of X-rays ; 5. The nature of X-rays: waves or corpuscles? ; 6. The discovery of X-ray diffraction and the birth of X-ray analysis ; 7. The first steps ; 8. The route to crystal structure determination ; 9. X-rays as a branch of optics ; 10. Early applications of X-ray crystallography ; 11. Unravelling the mystery of crystals - the forerunners ; 12. The birth and rise of the space-lattice concept

Readers of the Early Days of X-ray Crystallography from both camps will be rewarded by a thoroughly researched account on the multiple faces of a scientific specialty. Historians of science will find here a rich source for further study. Crystallographers will appreciate the lesson that the historical roots of their discipline are more ramified than it may appear from a mere rational reconstruction of ideas and concepts.