February 24: National Tortilla Chip Day? Really?

Some days are more crowded than others; Sunday, February 24 is not one of these.

Many of the Usual Suspects mention the Oscar telecast on Sunday night. Actually, we have read that many people actually do plan parties around the Oscar presentation. We just can't imagine why.

But, judging by the Usual Suspects, there isn't a lot to choose from on Sunday. Those that mention something other the Oscars tout National Tortilla Chip Day.

If you've forgotten about that one, it's probably already too late to send out Tortilla Chip Day cards -- but perhaps you could call dear friends and relatives to mark the occasion. Just don't be surprised if your dear friends and relatives start making plans for your involuntary commitment.

Here at The Blog of Days, we are all about giving you options, so permit us to offer these alternatives:

First, February 24 will be the Second Sunday of Lent.

February 24 is also the anniversary of the single most important legal decision in the history of the United States. On February 24, 1803, Chief Justice John Marshall handed down the Supreme Court's opinion in Marbury v. Madison. In Marbury, the Supreme Court declared that it has the power to determine whether a statute is, or is not, constitutional. The Constitution did not give the power of judicial review to the Supreme Court; rather, the Supreme Court invented it in this case. Every single constitutional challenge that has arisen, then, in the last 210 years proceeds from Marbury/

And we were initially quite surprised that none of our Usual Suspects tout February 24 as Calendar Day. It was on February 24, 1582 that Pope Gregory XIII promulgated what we still call (and use as) the Gregorian Calendar. You'd think calendar sites would be all over this one.

The Pope's introduction of the new calendar on February 24 may have been deliberate: February 24 was apparently the leap day under the old Julian calendar. At least, that's what we sorta, kinda understood after reading this passage in the Wikipedia entry on the Julian calendar (footnotes omitted):

The new leap day was dated as ante diem bis sextum Kalendas Martias, usually abbreviated as a.d. bis VI Kal. Mart.; hence it is called in English the bissextile day. The year in which it occurred was termed annus bissextus, in English the bissextile year.

There is debate about the exact position of the bissextile day in the early Julian calendar. The earliest direct evidence is a statement of the 2nd century jurist Celsus, who states that there were two halves of a 48-hour day, and that the intercalated day was the "posterior" half. An inscription from AD 168 states that a.d. V Kal. Mart. was the day after the bissextile day. The 19th century chronologist Ideler argued that Celsus used the term "posterior" in a technical fashion to refer to the earlier of the two days, which requires the inscription to refer to the whole 48-hour day as the bissextile. Some later historians share this view. Others, following Mommsen, take the view that Celsus was using the ordinary Latin (and English) meaning of "posterior". A third view is that neither half of the 48-hour "bis sextum" was originally formally designated as intercalated, but that the need to do so arose as the concept of a 48-hour day became obsolete.

There is no doubt that the bissextile day eventually became the earlier of the two days for most purposes. In 238 Censorinus stated that it was inserted after the Terminalia (23 February) and was followed by the last five days of February, i.e. a.d. VI, V, IV, III and prid. Kal. Mart. (which would be the 24th to 28th days of February in a common year and the 25th to the 29th days in a leap year). Hence he regarded the bissextum as the first half of the doubled day. All later writers, including Macrobius about 430, Bede in 725, and other medieval computists (calculators of Easter) followed this rule, as did the liturgical calendar of the Roman Catholic Church until 1970. However, Celsus' definition continued to be used for legal purposes. It was incorporated into Justinian's Digest, and in the English statute De anno et die bissextili of 1236, which was not formally repealed until 1879.

The effect of the bissextile day on the nundinal cycle is not discussed in the sources. According to Dio Cassius, a leap day was inserted in 41 BC to ensure that the first market day of 40 BC did not fall on 1 January, which implies that the old 8-day cycle was not immediately affected by the Julian reform. However, he also reports that in AD 44, and on some previous occasions, the market day was changed to avoid a conflict with a religious festival. This may indicate that a single nundinal letter was assigned to both halves of the 48-hour bissextile day by this time, so that the Regifugium and the market day might fall on the same date but on different days. In any case, the 8-day nundinal cycle began to be displaced by the 7-day week in the first century AD, and dominical letters began to appear alongside nundinal letters in the fasti.

During the late Middle Ages days in the month came to be numbered in consecutive day order. Consequently, the leap day was considered to be the last day in February in leap years, i.e. 29 February, which is its current position.

Of course, the complexity of the explanation is perhaps sufficient in itself to explain the reason why the Usual Suspects don't mention February 24 as Calendar Day.