Source: http://dcc.dickinson.edu/grammar/latin/reckoning-time
Timestamp: 2019-04-20 09:08:04+00:00

Document:
631. Dates, according to the Roman Calendar, are reckoned as follows.
a. The first day of the month was called Kalendae (Kalends).
Note— Kalendae is derived from calāre, to call—the Kalends being the day on which the pontiffs publicly announced the New Moon in the Comitia Calāta. This they did, originally, from actual observation.
c. On the seventh day of March, May, July, and October, but the fifth of the other months, were the Nōnae(Nones or ninths).
If the given date is the Kalends, add two to the number of days in the month preceding; if Nones or Ides, add one to that of the day on which they fall, and from the number thus ascertained subtract the given date.
e. The days of the Roman month by the Julian Calendar are given in the following table.
2 IV Nōn. Iān. IV. Nōn. Feb. VI. Nōn. Mārt. IV. Nōn. Apr.
3 III Nōn. Iān. III. Nōn. Feb. V. Nōn. Mārt. III. Nōn. Apr.
4 prīd. Nōn. Iān. prīd. Nōn. Feb. IV. Nōn. Mārt. prīd. Nōn. Apr.
6 VIII Īd . Iān. VIII. Īd. Feb. prīd. Nōn. Mārt. VIII. Īd. Apr.
7 VII Īd . Iān. VII. Īd. Feb. NŌN. MĀRTIAE VII. Īd. Apr.
8 VI Īd . Iān. VI. Īd. Feb. VIII. Īd. Mārt. VI. Īd. Apr.
9 V Īd . Iān. V. Īd. Feb. VII. Īd. Mārt. V. Īd. Apr.
10 IV Īd . Iān. IV. Īd. Feb. VI. Īd. Mārt. IV. Īd. Apr.
11 III Īd . Iān. III. Īd. Feb. V. Īd. Mārt. III. Īd. Apr.
12 prīd. Īd . Iān. prīd. Īd. Feb. IV. Īd. Mārt. prīd. Īd. Apr.
13 IDŪS IĀN. ĪDŪS FEB. III. Īd. Mārt. ĪDŪS APRĪLĒS.
14 XIX Kal. Feb. XVI. Kal. Mārtiās prīd. Īd. Mārt. XVIII. Kal. Māiās.
15 XVIII Kal. Feb. XV. Kal. Mārtiās ĪDŪS MĀRTIAE XVII. Kal. Māiās.
16 XVII Kal. Feb. XIV. Kal. Mārtiās XVII. Kal. Aprīlīs. XVI. Kal. Māiās.
17 XVI Kal. Feb. XIII. Kal. Mārtiās XVI. Kal. Aprīlīs. XV. Kal. Māiās.
18 XV Kal. Feb. XII. Kal. Mārtiās XV. Kal. Aprīlīs. XIV. Kal. Māiās.
19 XIV Kal. Feb. XI. Kal. Mārtiās XIV. Kal. Aprīlīs. XIII. Kal. Māiās.
20 XIII Kal. Feb. X. Kal. Mārtiās XIII. Kal. Aprīlīs. XII. Kal. Māiās.
21 XII Kal. Feb. IX. Kal. Mārtiās XII. Kal. Aprīlīs. XI. Kal. Māiās.
22 XI Kal. Feb. VIII. Kal. Mārtiās XI. Kal. Aprīlīs. X. Kal. Māiās.
23 X Kal. Feb. VII. Kal. Mārtiās X. Kal. Aprīlīs. IX. Kal. Māiās.
24 IX Kal. Feb. VI. Kal. Mārtiās IX. Kal. Aprīlīs. VIII. Kal. Māiās.
25 VIII Kal. Feb. V. Kal. Mārtiās VIII. Kal. Aprīlīs. VII. Kal. Māiās.
26 VII Kal. Feb. IV. Kal. Mārtiās VII. Kal. Aprīlīs. VI. Kal. Māiās.
27 VI Kal. Feb. III. Kal. Mārtiās VI. Kal. Aprīlīs. V. Kal. Māiās.
28 V Kal. Feb. prīd. Kal. Mārtiās V. Kal. Aprīlīs. IV. Kal. Māiās.
29 IV Kal. Feb. [prīd. Kal.
counted twice.] IV. Kal. Aprīlīs. III. Kal. Māiās.
30 III Kal. Feb. III. Kal. Aprīlīs. prīd. Kal. Māiās.

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