Specially written and designed for students in grades 7-10, each volume contains about 90 profiles of scientists throughout history and from all parts of the world. Sidebar stories, timelines, illustrations, and marginal definitions illuminate the text and each volume concludes with a comprehensive index. This continuing series introduces two volumes each year covering scientists, events and issues. Volume 4 covers figures such as Leif Erikson, Ibn Battuta, Ptolemy, Lewis & Clark, Neil Armstrong, Vasco da Gama, John Glenn, Marco Polo and many others.