This is a type study (of a primitive sort) on variations in 20th Century Disston No4 Mitre Box saws. I think i did this a few years back, and recently came across it again while testing the uploading of images to the gallery. The images are from various Disston catalogs on-line, notably Erik von Sneidern's http://www.disstonianinstitute.com/ an excellent resource for information on Disston saws. Some of the key identifying features are the number and placement of the saw screws and the label screws, the angle and shape of the back of the saw plate. Regards Ray