Table of Contents Tools of Discovery 4 Tools for Observation 10 Tools for Answering Questions 20 Tools for Experimenting 26 Tools for Analyzing and Communicating 36 Future Tools 40 Becoming a Scientist 45 Glossary 46 Index 47 Show What You Know 47 Websites to Visit 47 About the Author 48
Tools of Discovery In 1676 Antonie van Leeuwenhoek peered at a drop of water through a magnifying lens he made himself Using this scientific tool the self-taught scientist made an amazing discovery tiny creatures he called animalcules They were protozoa single-celled creatures No one had seen them before Originally a cloth merchant van Leeuwenhoek probably used magnifying glasses to examine cloth as part of his business The tool helped merchants look at threads up close and determine the cloth’s quality Eventually van Leeuwenhoek became obsessed with making ever more powerful magnification devices His lenses were capable of magnifying objects over 200 times making them far more powerful than microscopes used at the time 4 van Leeuwenhoek 1632 1723
The protozoa van Leeuwenhoek observed were isolated from sources such as rainwater pond water and the human mouth The use of magnification tools dates back to Roman times Emperor Nero used a piece of emerald to help him see better Until the 1600s most lenses could only magnify things up to 10 times Van Leeuwenhoek refused to share his secrets for making his lenses and using light to illuminate his specimens For 100 years after van Leeuwenhoek died in 1723 no one saw his animalcules again 5
