Because of the drought, William’s family couldn’t afford to send him to school anymore. So one day William went to the library near his home. He wanted to continue his education. William found a science book called Using Energy. It included instructions for building a windmill. Windmills can be very efficient sources of electricity, and they can bring water up from underground. William didn’t know much English, and he wasn’t able to understand most of the book, but it was full of pictures and diagrams. Looking at the pictures, William thought he could build a windmill for his family.