She also covers how to make your own natural household products. In this book she uses an electronic device which she calls a zapper. She describes how to make it. She also tells you how to make an electronic device for rating pollutants in and on various things, including animals and birds. An example of how thorough she is and how simple she explains things - is her explanation of our hands.
Hands do everything.
They pick up things from the floor. They handle money. They touch other peoples' hands. They clean up bottoms. They touch all kinds of door knobs.