2406. Numbers are noted by combinations of the characters #I# = 1; #V# =
5; #X# = 10; ↆ, later [--], [--], or #L# = 50; #C# = 100; #D# = 500;
ↀ or [--], post-Augustan M = 1000.
2407. Of these signs, #V# seems to be the half of #X#, which may be
Etruscan in origin. The original signs for 50 and 1000 were taken from
the Chalcidian Greek alphabet (18, 19), in which they represented sounds
unknown to early Latin. Thus, ↆ, in the Chalcidian alphabet representing
#ch# (49), was used by the early Romans for 50, and became successively
[--], [--], and #L#. The form ↆ, is found very rarely, [--] oftener, in
the Augustan period; [--] is common during the last century of the
republic and in the early empire; L, due to assimilation with the Roman
letter, appears in the last century of the republic. The sign for 1000
was originally ↀ (Chalcidian #ph#); it became [--] (the common classical
form), [--], or [--]; the form #M# as a numeral appears in the second
century A.D., although M is found much earlier as an abbreviation for
#mīllia# in M · P, that is #mīllia passuum#. For 100, the sign Θ
(Chalcidian #th#) may have been used originally; but C (the abbreviation
for #centum#) came into use at an early period. The sign #D#, = 500, is
the half of ↀ.
2408. To denote 10,000 the sign for 1000 was doubled: thus, ↂ, written
also [--], [--], [--]. Another circle was added to denote 100,000: thus,
ↈ, written also [--], [--], [--]. The halves of these signs were used
for 5000 and 50,000: thus, ↁ and ↇ; variations of these last two signs
are found, corresponding to the variations of the signs of which they
are the halves.
2409. From the last century of the republic on, thousands are sometimes
indicated by a line drawn above a numeral, and hundreds of thousands by
three lines enclosing a numeral: as, #V̅# = 5000; [--] = 1,000,000.
2410. To distinguish numerals from ordinary letters, a line is often
drawn above them: as, #V͞I# = 6. This practice is common in the Augustan
period; earlier, a line is sometimes drawn across the numeral, as, [--]
= 2; [--] = 500.
2411. Of the two methods of writing the symbols for 4, 9, 14, 19, &c.,
the method by subtraction (#IV#, #IX#, #XIV#, #XIX#, &c.) is rarer, and
is characteristic of private, not public inscriptions.
[Erratum:
2410 ... a line is sometimes drawn across the numeral
_examples show that “across” means “through”, not “above”_]