The typography of the Compact OED

The OED Compact Edition was printed from exactly the same typeset output as the OED Second Edition, photographically reduced. For the Second Edition, the typesetting system composed complete three-column pages at full size, complete with headlines, which were output on a Monotype Lasercomp, with a resolution of 1000 lines per inch. These bromide pages were sent to the USA for printing. For the Compact Edition, the bromide pages were returned to the UK and pasted up on to boards with nine pages to view per board. The first and last headline words for the whole board were then typeset and pasted on to the boards above the pages to act as the headlines for the Compact Edition. The artwork boards were sent back to the USA, where they were photographically reduced to 37% linear on to film. This film was used to make the printing plates of the Compact Edition. The this use of first-generation Lasercomp output, with only one intermediate film reduction stage, helps explain the sharpness of the type in the Compact Edition.

The proportions of Monotype Imprint (left) and Imprint A, used in the OED

The main type use for the Second Edition was Monotype Imprint A, a variant of the Imprint typeface optimized for setting at 6 and 7 point. Two sizes were used: the main part of each entry was set in a nominal size of 7.5 pt with line spacing of 7.75 pt (in shorthand, 7.5 on 7.75 pt), the quotation banks were set in 6 on 6 pt. The 37 per cent linear reduction means that the ‘point sizes’ of the type in the Compact Edition are therefore 2.775 on 2.8675 pt and 2.22 on 2.22pt. But these figures are difficult to comprehend, because typefaces with the same nominal point size can have different appearing sizes, depending on the weight and proportions of the letterforms. It may be easier to express the sizes in relation to normal reading text. A normal Oxford academic book of the same period might be set in 11 on 12 pt Imprint (the normal version of Imprint). This has a cap-height of 2.586 mm and an x-height of 1.6 mm. (Cap-height is the height of the letter H, x-height the height of the letter x.) The cap-height and x-height of the larger type in the Second Edition are 1.875 mm and 1.155 mm. The figures for the Compact Edition are 0.693 mm and 0.428 mm, so the larger type is about a quarter of the size we normally expect to read.

It should be remembered that the Compact Edition was supplied with a magnifying glass, and was not intended to be read unaided. The legibility of the Compact Edition is helped by the very short column width. I find that I can read both the larger and the smaller type in the Comact Edition unaided, but that it is tiring. I find it easier to read the shorter paragraphs in the larger type, but I find it difficult to read the smaller type without skipping or re-reading lines. So, for me, the practical limit for reading in terms of x-height is about 0.4 mm. Other readers may find they have different thresholds.