Book excerpt: This dictionary provides an authoritative and accessible guide to the lives, labours and achievements of the men and women who have shaped the world of science. The in-depth biographies are comprehensive in their coverage of scientists and provide a wealth of information about the great scientists and their idiosyncrasies - for example, the effect of Humphrey Davy's jealousy of his former protege Michael Faraday, the prejudice against women that barred Lize Meitner from working in a major laboratory, and why the astronomer Tycho Brahe wore a false nose.