Ash Wednesday 1776 was on February 21

Ash Wednesday is a Christian observance marking the start of Lent, a period of fasting, repentance, and reflection. On this day, ashes are typically applied in the shape of a cross on the foreheads of believers as a symbol of mortality and penance. It occurs 46 days before Easter Sunday.

Easter Sunday 1776 was on  April 07 

See Catholic Calendar for 1776

 
Falat Julian, Popielec