Pierre,

I am not sure if this is what you are looking for Poland 1794. I think you want this detail but for later period:

http://upload.wikimedia.org/wikipedia/commons/7/7c/1794_Laurie_and_Whittle_Map_of_Poland_and_Lithuania_after_Second_Partition_-_Geographicus_-_Poland-lauriewhittle-1794.jpg

Click on image to enlarge.

Map of departments:

https://scontent-b-sjc.xx.fbcdn.net/hphotos-xfa1/v/t1.0-9/s720x720/1002292_489081787837719_1772609364_n.jpg?oh=c2c09de533069dbea891de67c3e6358d&oe=54DB9C03

This Wiki page shows the changes over time to the administrative districts:

http://en.wikipedia.org/wiki/Duchy_of_Warsaw

Steve