The following table lists old English paper and board sizes as used in the printing trades in Britain. With the advent of metrication, many of these have fallen into disuse but are provided here as a reference source for those who may need to identify a particular reference chanced upon elsewhere.
Measure Size (inches) Measure Size (inches)
Writing and Printing Papers Printers' Cards & Blanks (Cont.)
Foolscap  13½  x  17     Large      3  x  4½
Foolscap, Double 17  x  27 Court  3½  x  4½
Foolscap, Oblong Double  13½  x  34     Double Small  35/8  x  4¾
Foolscap, Quad 27  x  34 Large Court  4  x  5 
Pinched Post  14½  x  18½ Duke (or official)  3½  x  5½
Post  15¼  x  19     Extra Large  41/8  x  57/8
Post, Double      19  x  30½ Intimation  35/8  x  6    
Large Post  16½  x  21     Double Large  4½  x  6    
Large Post, double 21  x  33 Cabinet  4½  x  6½
Demy   17½  x  22½  Post 8vo  4½  x  7    
Demy, Double   22½  x  35      Double Official  5½  x  7    
Demy, Quad 35  x  45 Quad Small  4¾  x  7¼
Medium 18  x  23 Large Post 8vo 5  x  8
Medium, Double 23  x  36 Quad Large 6  x  9
Royal 20  x  25 Royal 8vo  61/8  x  97/8
Royal, Double 25  x  40 Royal 4to  97/8  x 123/8
Crown, Double 20  x  30 Boards
Crown, Quad 30  x  40 Index Boards
Imperial 22  x  30 Index Royal 20½  x  25½
Imperial, Double 30  x  44 Index Royal and a Half 25½  x  30½
Printers' Cards & Blanks Pulp Boards
Thirds 1½  x  3    Pulp Royal 20½  x  25    
Extra Thirds 1¾  x  3    Postal  22½  x  28½
Town 2  x  3 Imperial 22½  x  30    
Duchess     3  x  57/8 Paste, Duplex, Triplex and Ivory Boards
Rex 3¼  x  5    Paste Royal 20½  x  25    
Reduced Small  21/8  x  3½ Postal  22½  x  28½
Diamond  3½  x  5¼ Paste Imperial 22½  x  30    
Baronet  3½  x  5¾ Cover Papers
Small  23/8  x  35/8 Cover Medium  18½  x  23½
Imperial Card  3¾  x  5¾ Cover Royal  20½  x  25½
Extra Small  2½  x  1/8 Cover Double Crown  20½  x  30½