Complex sentence: While blessing the cornerstone of the Chapelle Expiatoire he demanded, though in vain, an amnesty for the exiled members of the Convention; and the ordinance of 1828, disbanding the Jesuits and limiting the recruiting of the clergy, was issued against his advice.
Split into simpler sentences: While blessing the cornerstone of the Chapelle Expiatoire, he requested in vain an amnesty for the exiled members of the Convention. The ordinance of 1828, disbanding the Jesuits and limiting the recruiting of the clergy, was also issued against his advice.