I found this old tool out in my field. Must be pretty old!
I don"t even see a trademark, part number, or patent date on it!
<img src = "http://i167.photobucket.com/albums/u125/27Grainfield/Stuff/stone1_zps1c1fae1c.jpg">
<img src = "http://i167.photobucket.com/albums/u125/27Grainfield/Stuff/stone2_zps5ff7080e.jpg">
<img src = " http://i167.photobucket.com/albums/u125/27Grainfield/Stuff/stone3_zps79f69ed8.jpg">
I don"t even see a trademark, part number, or patent date on it!
<img src = "http://i167.photobucket.com/albums/u125/27Grainfield/Stuff/stone1_zps1c1fae1c.jpg">
<img src = "http://i167.photobucket.com/albums/u125/27Grainfield/Stuff/stone2_zps5ff7080e.jpg">
<img src = " http://i167.photobucket.com/albums/u125/27Grainfield/Stuff/stone3_zps79f69ed8.jpg">