My father was a master of several crafts—mason, carpenter, roofer, woodworker. He believed that for every manual task to be performed there was a special and necessary tool. Among the most curious was the small metal device with which you scored and "cut" glass to fit in a window. Cutting glass has a finality about it. Sometimes when you are working with stone or brick or wood, you can be slightly off in your measurements, and the piece can still be made to fit. You can mortar it into place or nail it down or shim it up. With glass, you must snap off the piece the first time, or it breaks into slivers and fragments, and you have to start again. There are no second chances.