After graduation from the University of Copenhagen in physics and chemistry, and a period as a high school teacher, Helge Kragh became Associate Professor at Cornell University, Departments of History and Physics. Later, he took positions as Curator at the Steno Museum for Science and Medicine and Professor of the History of Science at the University of Oslo. Since 1997, he has been Professor of the History of Science and Technology at Aarhus University, Denmark. He is a member of the Royal Danish Academy of Sciences and Letters, the International Academy for History of Science, and the European Academy of Science. From 2008-2010, he was President of the European Society for History of Science.

Kraghs book is not a light read, but for those interested it is fascinatingly detailed and wonderfully researched ... This is definitely a book for the determined but it is an eminent rewarding for those who make the effort.

• 1. Atomic theory before 1913 ; 2. On the constitution of atoms and molecules ; 3. Reception and early developments ; 4. The Bohr-Sommerfeld theory ; 5. A magic wand ; 6. Molecules and other failures ; 7. A theory of the chemical elements ; 8. The end of the Bohr atom ; 9. Appendix: The philosophers' atom

After graduation from the University of Copenhagen in physics and chemistry, and a period as a high school teacher, Helge Kragh became Associate Professor at Cornell University, Departments of History and Physics. Later, he took positions as Curator at the Steno Museum for Science and Medicine and Professor of the History of Science at the University of Oslo. Since 1997, he has been Professor of the History of Science and Technology at Aarhus University, Denmark. He is a member of the Royal Danish Academy of Sciences and Letters, the International Academy for History of Science, and the European Academy of Science. From 2008-2010, he was President of the European Society for History of Science.

Kraghs book is not a light read, but for those interested it is fascinatingly detailed and wonderfully researched ... This is definitely a book for the determined but it is an eminent rewarding for those who make the effort.

• 1. Atomic theory before 1913 ; 2. On the constitution of atoms and molecules ; 3. Reception and early developments ; 4. The Bohr-Sommerfeld theory ; 5. A magic wand ; 6. Molecules and other failures ; 7. A theory of the chemical elements ; 8. The end of the Bohr atom ; 9. Appendix: The philosophers' atom

After graduation from the University of Copenhagen in physics and chemistry, and a period as a high school teacher, Helge Kragh became Associate Professor at Cornell University, Departments of History and Physics. Later, he took positions as Curator at the Steno Museum for Science and Medicine and Professor of the History of Science at the University of Oslo. Since 1997, he has been Professor of the History of Science and Technology at Aarhus University, Denmark. He is a member of the Royal Danish Academy of Sciences and Letters, the International Academy for History of Science, and the European Academy of Science. From 2008-2010, he was President of the European Society for History of Science.

Kraghs book is not a light read, but for those interested it is fascinatingly detailed and wonderfully researched ... This is definitely a book for the determined but it is an eminent rewarding for those who make the effort.

• 1. Atomic theory before 1913 ; 2. On the constitution of atoms and molecules ; 3. Reception and early developments ; 4. The Bohr-Sommerfeld theory ; 5. A magic wand ; 6. Molecules and other failures ; 7. A theory of the chemical elements ; 8. The end of the Bohr atom ; 9. Appendix: The philosophers' atom