Well, at that time, the sewerage system had not yet been invented. For the royal family there were arrangements made though, they had special poop-chairs. It looked like chairs with a big hole in it,...
It was a palace when there used to live kings [i.e: Marie Antoinette]. In that palace lived the king the queen and sometimes their families as well. Now is just a museum.
The former home of the French Monarchy, today a big tourist attraction. The two houses of the French Parliament occassionally meet here to see the President, or to discuss changes to the constitution.