Fonctionnement - A disc to predict week days

1. Select a year

2. Place the desired month under the year. If it is a leap year (they are indicated in red), choose the months of January or February in red. 

3. find the day number you are looking for. 

4. Above the number you will find the corresponding day of the week. 

In this example, the 25 of December 2044 will be a Sunday!