The palace has undergone alterations and additions, e.g.
in 1689 made no alterations of importance.
After extensive alterations, Bird Song, a bed and breakfast, was born.
Fundamental alterations were made upon them: their wooden tubes were replaced by tubes of metal; 1 Description de l'observatoire central de Pulkowa, p. 208.
It was restored to sacred uses in 1887, and has been carefully liberated from later alterations (U.