note zengargoyle <p>I don't remember the details, but IIRC <b>grads</b> are used in range finding. Something along the lines of: <ul><li>you know the tank (boom boom) is 20 feet long. <li>in my binoculars (with a grad scale on the inside) the tank spans 10 grads. <li>the tank is (20/10)x100 feet away. </ul> <p>I either read this in some Army field manual or maybe my father tried to explain it to me. 199426 199510