Science is built up of facts, as a house is built of stones; but an accumulation of facts is not more a science than a heap of stones is a house.

Did you know that for most of history, people thought that blood didn't move in the body at all? Enter William Harvey, the man who is credited with discovering the circulation of the blood. In a series of classic experiments, Harvey established the role of the heart and a modern picture of the circulatory system. As a typical experiment, he put a tourniquet on someone's arm, then, after the veins popped, pressed on them to see which direction was "downstream." This is how he discovered that blood in the veins always flows toward the heart.

In 1955 at the University of Chicago, Harold Urey and Stanley Miller performed an experiment that demonstrated how the first step in chemical evolution may have taken place. They combined methane, hydrogen, ammonia, and carbon dioxide -- the materials believed to be the components of the earth's early atmosphere -- and subjected the mixture to electrical sparks (thus simulating the effects of lightning). In a matter of hours they noticed that the constituents of early earth were forming molecules known as amino acids, which are the basic building blocks of proteins. In other words, Miller and Urey, starting with nonliving materials, had produced the simplest materials that make up the living cell.

In 1919, Arthur (later Sir Arthur) Eddington made what most people regard as the most dramatic and best-known confirmation of the theory of relativity. Traveling to the coast of Africa to observe a solar eclipse, he noted that the position of stars near the edge of the sun appeared to be shifted during the eclipse, a shift that could only occur if light from the stars were bent as it went around the sun.

The regularly spaced signals from a pulsar (cosmic source of pulses of radiation) look a lot like an attempt at communication from extraterrestrials. In fact, when astronomers in England first detected them in the late 1960s, they were referred to as LGM ("little green men") signals by people in the observatory.

If you find any or all of the above facts fascinating, perhaps you are a scientific type at heart. What kind of person do you need to be to most successfully enter the world of science? Take the following quiz, answering yes or no to each question. You may discover that you are, indeed, a scientific type and that one of the careers profiled within this book might be just perfect for you!

1. Do you enjoy working on long-term projects?

2. Are you a self-starter who can work alone?

3. Can you deal with "failures" -- situations that don't produce the predicted result -- effectively?

4. Do you have a long attention span?

5. Can you work effectively as part of a team?

6. Do you enjoy working independently on a day-to-day basis?

7. Is the idea of exploring the unknown interesting to you?

8. Do you have a strong interest in the world of science?

9. Are your math skills adequate?

10. Are you willing to earn at least a bachelor's degree?

11. Do you have strong skills in logic and problem solving?

12. Do you have a wish to be a part of something that could provide an advancement for the betterment of humanity?

Scientific types and those with inquiring minds have made incredible contributions to society since the beginnings of recorded history. Are you interested in joining that group? This book will outline a wide variety of careers that are options for you. The list is certainly not all inclusive but does provide a variety of possibilities.

Perhaps someday your name will be listed along with other scientific types mentioned in the pages of this book!