Fear of today’s date is known as paraskavedekatriaphobia or friggatriskaidekaphobia. The origin of this Friday the 13th superstition is highly debated. Both the day Friday and the number 13 have been seen as unlucky throughout history: there were 13 diners at the Last Supper and at a disastrous banquet at Valhalla in which Loki was the uninvited 13th guest. In addition, the Crucifixion is said to have occurred on a Friday, and Friday was called the Witches’ Sabbath in the Middle Ages, since it was a holy day for pagan religions. Friday the 13th, then, might be a simple combination of the two ill-fated pieces.
Friday, October 13, 1307 is also said to be the day that hundreds of the Templar Knights were arrested, later to be tortured and executed—so perhaps the coupling of Friday and the 13th as unlucky was not so accidental after all.
Accidentl* is a typo of high probability on the Ballard list, though some of these hits are transcriptions from titles pre-1800s. Many of the other occurrences are in the plot summaries of detective films: characters in library catalogues seem to be constantly “accidently” witnessing murders.
(Black cat photograph from Bianca Inez’s Flickr photostream)