On the other side of the card we see that the card is written in Wilna on 13 May 1885. This is our Gregorian date. In the postmark above we a great difference: an much earlier date: 29 АПР, the abbrevation for АПРЕЛЬ (APREL = April): 12 days must be added in the period after 28 February through 28 February 1900 to the Julian date for converting it to our Gregorian date.