Comparison of solid magnet with one Of square iron wire, 6. Comparison Of magnets of round bar iron with hollow cylindrical magnet, 7. Â Characteristics Of magnets for lifting and for attracting from a distance, 8. Â Advantages Of hollow and solid magnets, 8. Comparison Of square wire magnets with square solid magnets, 9.
Books can be attributed to "Unknown" when the author or editor (as applicable) is not known and cannot be discovered. If at all possible, list at least one actual author or editor for a book instead of using "Unknown".
Books whose authorship is purposefully withheld should be attributed instead to Anonymous.