each chapter in the book ends with a number of exercises. if i haven't used them in two years, they are gone. ...and be sure to read the notes and links at the foot of the page for more information on magnetic free energy motors. natural fully visual header, footer and page builder. at the beginning of my final semester of grad school, i presented the lighthouse book to my advisor. good shot, contrast and perspective, nice shown time and green trees. although this helped a little, more needs to be done to correct the issue. 