In 1777 Samuel Miller of Southampton, England, received the first patent for a circular saw. His wind- powered machine's usefulness was limited, however, for want of a more powerful energy source. Thirty-six years later Tabitha Babbit, a Shaker woman from the Harvard Shaker village, invented a circular saw of her own. Her religious beliefs prevented her from seeking a patent, but the new invention became popular in her community. Babbit's saw was initially human-powered, but waterwheels and steam were soon harnessed for added convenience and efficiency. Sawmills adopted the circular saw, and the tool was soon at the heart of the lumber industry.
The circular saw is a relatively simple device that dramatically improves on the efficiency of a standard handsaw, where half of each stroke is wasted effort. Circular saws cut by spinning circular serrated blades at high speeds into the timber passed through them.
The U.S. military, bolstering its technology for World War II, enlisted the saw manufacturer Skilsaw to develop a specialized saw for military use. Skilsaw's answer, the PS-12 military circular saw, could function in all conditions, including underwater, and came with a rugged camouflage paint job. The U.S. Navy put the saw into camouflaged boxes, and began floating secret circular-saw units to predefined landing areas.
Nowadays the circular saw is an industrial staple. Portable circular saws allow users to saw small jobs, miter saws permit all angles of cutting, and table saws provide the backbone of most woodworking shops. Numerous blades have also been created to optimize saws for particular cutting purposes. Specialized blades, with intriguing names such as "ripping," "dado," and "thin kerf," are designed to cut through materials as varied as brick, steel, and glass.
