Window Glass.

Rules as to Fractional Parts of an Inch.

British Plate.

—Pilkington’s “Glass Cutter’s Assistant” gives the following: Polished, Silvered, and Rough Cast. All fractional parts of inches will be charged as full inches, e.g., 1051⁄8 × 571⁄4 be reckoned as 106 × 58.

Rolled Plate Glass.

—Every fraction above 1⁄6 of an inch is charged as an inch, e.g.,

471⁄6×201⁄8is reckoned47×20
581⁄4×321⁄4„59×33