Looking at the image here, who hasn’t ever asked him or herself, how to hang picture frames straight and level in their homes or office? It would be fairly safe to say: no one, because just about everyone we know of has had to deal with this issue at one time or another. It has to be one of life’s great small annoyances, especially when or if you're having visitors at home. Why this happens has to to with physics. The natural elements, everyday events and happenings can transmit, impart or exert unseen, but real, forces. A gust of wind via a doorway left open will most likely be string enough to move a photo frame on a wall. A ...