March 5, April 1, May 3, June 6, July 1, August 4, September 0, October 2, November 5, December 0. To avoid confusion with other calendars, the last consonant in the following words is used to indicate these numbers:—Jan, Feeble, Marshal, Apricot, Madam, Jew, Juliet, Augur, Sepoys, Octoroon, Novel, Disease. The numbers can also be recollected by the sentence—"No lily—to match—a dress—in lace." In leap years the number for January is 1, and for February 4; the rest are unaltered. To find the day of the week any date in any year falls upon, the last two figures of the year are to be divided by seven and the remainder added to the number of leap years (found by dividing by four). To this is added the month number and the day of month required. The whole is divided by 7, and the remainder gives day of week. To find, for instance, upon what day the battle of Waterloo was fought, June 18th, 1815, the two last figures, 15, are taken.
| 15 divided by 7 gives 2, plus | 1 |
| Divided by 4=3, plus 3 | 3 |
| Add day of month | 18 |
| Add month number | 6 |
| Total | 28 |
28, divided by 7 gives no remainder, hence date wanted fell upon a Sunday. To elucidate the method still further the date of Christmas Day, 1888, may be taken.
| 88 divided by 7 gives 12, plus 4 | 4 |
| Divided by 4=22 | 22 |
| Add day of month | 25 |
| Add month number | 0 |
| Total | 51 |
51 divided by 7 gives 2 as a remainder. This indicates the second day, or Tuesday. A little practice enables any date to be mentally calculated very quickly. The chief point to be remembered is that when divided by 7, the remainder is to be included, but when divided by 4, the remainder is to be discarded.
