Wednesday "Germanic Mercury". The Latin name dates to the late 2nd or early 3rd century. It is a calque of Greek ("heméra Hérmou"), a term first attested, together with the system of naming the seven weekdays after the seven classical planets, in the "Anthologiarum" by Vettius Valens (c. AD 170). The Latin name is reflected directly in the weekday name in most modern Romance languages: "Mércuris" (Sardinian), "mercredi" (French), "mercoledì" (Italian), "miércoles" (Spanish), "miercuri" (Romanian), "dimecres" (Catalan), "Marcuri" or "Mercuri" (Corsican). In Welsh it is Dydd Mercher, meaning Mercury's Day. The German name for the day, "Mittwoch" (literally: "mid-week"), replaced the
Determination of the day of the week where is the day of the week (counting upwards from 1 on Sunday instead of 0 in Gauss's version); and , , and are numbers depending on the day, month, century and year which are tabulated in the "Complete table: Julian and Gregorian calendars" above. Note that the numbers tabulated for y can also be described by the following equation: Where So, for example, if you want to find 'y' for the year 1987: In Zeller’s algorithm, the months are numbered from 3 for March to 14 for February. The year is assumed to begin in March; this means, for