Antique bed mattresses: the three-quarter and the inch that is missing

The three-quarter

A three-quarter is 48 × 75 in (122 × 191 cm)¹; three-quarter beds were common from the late 1800s through the 1930s¹. Beside it, a twin is 38 × 75 in (97 × 191 cm)² and a double 54 × 75 in (137 × 191 cm)²: nothing in a store is the right width.

The inch that is missing

antique frames often deviate from the nominal size by an inch or two¹. A store double on an antique double frame either does not drop between the rails or sits on them and rocks. Measure the frame, not the label on the old mattress.

Measuring an old frame

• Rails with angle-iron or wooden ledges: measure between the rails' inside faces, head and foot. The slats or the spring sit on the ledges; the mattress sits between the rails.
• A rope or a wire spring: measure the opening of the frame, and tell the maker what the support is — a soft support wants a mattress that does not need a rigid base.
• Head board and foot board: inside face to inside face, both sides, smaller number.
• Posts in the corners: if they stand proud of the rails, that is a notch, two numbers per post.