In these articles Professor Brooke has aimed to expose and explore the many layers of philosophical debate that accompanied the development of chemistry in the 100 years from Priestley to Kekulé. During this period the foundations of our modern science were laid: Lavosier’s ’chemical revolution’, Dalton’s atomic theory, the electrochemical concepts of Berzelius transformed the science, as did new ideas of valency and molecular structure. But it was also a period of intense controversy when chemists called each other brigands and assassins.