Armelin's calendar was developed around 1887 by French astronomer Gaston Armelin [Wikidata], who developed a twelve-month calendar in which the year of 364 days was divided into four equal quarters of 91 days.
Armelin's calendar proposal was discussed chiefly under the auspices of the Société astronomique de France in 1887 and recently in the French Academy of Sciences.
The day of the week on which each month starts can be memorized.
[1] A major disadvantage is for sabbatarians, who are obliged to worship every seventh day.
Armelin's project received the first premium of the French Astronomical Society.