I went to the county library to get a book on Biology 101. I took out the one that looked most promising among the small set of choices. It's called "The Nature of Life" by Postlethwaite and Hopson. It seems like an OK book, but I read this paragraph on page 30 and now I wonder what kind of reputation it has. I have the third printing of the first edition, and I believe it is out in a third edition now, so this may have been repaired already. The paragraph gives an explaination for the stability of the atom. Because the nucleus contains both positively charged protons and chargeless neutrons, it has an overall positive charge; by contrast, the orbiting electrons have a negative charge. The attraction between these positive and negative charges pulls the electrons toward the nucleus, but the centrifugal (outward pushing) force of the rapidly orbiting electrons tends to throw them outward, away from the nucleus, like the force of a rock tied to a twirling string. A balance reached between the attractive and centrifugal forces holds the electrons in orbit at a set distance from the nucleus. For the benefit of any non-physicists here, this is whole cloth. This explaination is wrong from both a classical and a modern (quantum mechanical) point of view. I will probably continue reading the book unless I find out that it has a bad reputation. I note that Amazon.com, which usually has customer reviews, has none for this book.