11 Numbers and dates

11.4 Roman numerals

The base numerals are I (1), V (5), X (10), L (50), C (100), D (500), and M (1,000). The principle behind their formation is that identical numbers are added (II = 2), smaller numbers after a larger one are added (VII = 7), and smaller numbers before a larger one are subtracted (IX = 9). The I, X, and C can be added up to four times:

I, II, III, IV, V, VI, VII, VIII, IX, X (10)
XI, XII, XIII, XIV, XV, XVI, XVII, XVIII, XIX, XX (20)
MCCCCVIII (1408)

If possible, avoid eliding Roman numerals. To save space in certain circumstances two consecutive numerals may be indicated by f. for ‘following’: pp. lxxxvii–lxxxviii becomes pp. lxxxvii f.

Roman numerals can be difficult to interpret and may cause design problems because of the variable number of characters needed to express them. For example, they may be best avoided in tabulated lists, such as contents pages, because the alignment of the numerals and the following matter can produce excessive white space on the page:

I

II

III

IV

V

VI

VII

VIII

IX

X

Oxford’s use of Roman numerals is described below:

  • • Capital Roman numerals are used for the chapters and appendices of a book, for acts of plays or sections of long poems, and for volume numbers of multi-volume works:

    Act I of The Tempest

    Book V

    Chapters III–VIII

    Volume XVI Soot–Styx

  • • The division label (part, book, chapter, appendix, etc.) is styled in the same height as the numeral, capital with capital, lower case with lower case, and small capital with small capital. Thus Chapter XI, chapter xi, chapter xi.

  • • Lower-case Roman numerals are used to number the preliminary pages in a book, and for scenes of plays:

    pp. iii–x

    Hamlet, Act I, sc. ii

  • • When Roman numerals are used in references, they are lower case if there is only one level, small capital and lower case in that order if there are two (ii. i), full capital, small capital, and lower case in that order if there are three (III. ii. i).

  • • Capital Roman numerals are used after the names of monarchs and popes: Henry VIII (no full point). The number should not be written as an ordinal (Henry the VIIIth), although the style Henry the Eighth is an acceptable alternative to figures in running text.

  • • Capital Roman numerals are similarly used in American personal names, where the male of a family bears the same name: Adlai E. Stevenson III, Daniel P. Daly V. A male bearing his father’s name is styled Jr, whereas a male bearing his grandfather’s name—but not his father’s—is styled II.

  • • Roman numerals in manuscript sometimes have a final or single i replaced by a j, for example ij, viij. This style need be retained only when reproducing copy in facsimile.

  • • In editions of Latin texts, Roman numerals should generally be set in small capitals. Classical scholars tend to make little use of Roman numerals, both in classical reference (Ovid, Amores 3.1.15 not iii.i.15) and in volume numbers of books.


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