Of all the glazier's tools, the glass cutter has undergone the most change since Gothic times. Diamond-tipped cutters of the 14th-16th centuries were replaced in 1869 by the wheel cutter. Look closely for the small carbide-steel wheel at the tip of the cutter head. It's only about 1/8

Of all the glazier's tools, the glass cutter has undergone the most change since Gothic times. Diamond-tipped cutters of the 14th-16th centuries were replaced in 1869 by the wheel cutter. Look closely for the small carbide-steel wheel at the tip of the cutter head. It's only about 1/8" (4mm) in diameter. This tiny little wheel cut every single piece of glass in the Windows for Christ Church! Pretty good mileage, huh?