Two patent applications were made January 29, 1925 covering the Block Optic line. Some molds included the Block Optic feature while other non-optic molds were used and an optic was applied. Collectors call this "Honeycomb" optic.
The Martha Washington Line items were introduced starting in 1927 as the Centennial Line. Centennial line numbers were not always the same as Martha Washington line numbers. Where the shapes matched, the Centennial number is shown in the description of the Martha Washington items and size differences are noted. In the 1931 catalog supplement, the line was reference as "Victorian Period" Glassware. The item numbers match the Martha Washington line numbers.
The Stratford line was introduced in late 1921 or early 1922 and was first advertised as Old English Stratford. Stratford has larger diamonds or pyramids than the similar Mount Vernon line introduced in 1931.
The Wetherford line first appeared in trade advertising in 1926 and appeared again in the 1927 Cambridge catalog. The name was spelled "Wetherford" on both catalog pages while the name was spelled "Weatherford" in trade advertising. The line was apparently discontinued before 1930. Many items will have engraving #39 which is 6 closely spaced gray-cut lines.