The word pope—in Latin _Papa_, and by initials _PP._—was once common to all bishops, and even to simple priests and clerics; but when certain schismatics of the eleventh century began to use it in a sense opposed to the supreme fatherhood of the Roman Pontiffs over all the faithful, clergy as well as people, it was reserved as a title of honor to the bishops of Rome exclusively. Cardinal Baronius says, in a note to the Roman Martyrology, that St. Gregory VII. held a synod in Rome against the schismatics in the year 1073, in which it was decreed “_inter alia plura, ut _PAPÆ_ Nomen unicum esset in universo orbe Christiano, nec liceret alicui seipsum, vel alium eo nomine appellare_.”[38] Another singularity about one of the pope’s titles deserves to be noted. The word _Dominus_ in Latin—lord—was originally used only of Almighty God, and a contracted form—_Domnus_—was employed in speaking of saints, bishops, and persons of consideration; but in course of time, although a vestige of the once universal custom still lingers in the _Jube Domne benedicere_ of the Office recited in choir, the term _Domnus_ came to be specially reserved to the Roman Pontiff, for whom we pray in the litany as _Domnum Apostolicum_. Cancellieri, who, as usual, has sought out an abstruse subject, gives everything that can be said upon the matter in his _Lettera sopra l’Origine Delle Parole Dominus e Domnus e Del Titolo Don che Suol Darsi ai Sacerdoti ai Monaci ed a Molti Regolari_. In Roma, MDCCCVIII. Footnote 30: The apostolic chamber, called in Rome the _Reverenda Camera Apostolica_, dates from the pontificate of Leo the Great, who constructed in the year 440 a small but elegant suite of chambers which served as a sanctuary for the bodies of the apostles SS. Peter and Paul until proper crypts, called _Confessions_, had been prepared for them beneath the high altars of their respective basilicas at the Vatican and on the Ostian Way. When these relics had been deposited in their present resting-places, the Leonine sanctuary was used, as a strong and venerable place, to contain the public treasury of the Holy See, which was given into the safe-keeping of certain officials called _camerarii_. Their successors are the present _chierici di camera_, who are eight in number and form one of the great prelatic colleges of Rome. The present institution was reorganized by Pope Urban V. in the fourteenth century. The cardinal-chamberlain is _ex officio_ its head, and it acts as a board of control over the finances. Footnote 31: It is known to all visitors to Rome that Pius IX. prepared a beautiful tomb for himself before the high altar of St. Mary Major’s. Footnote 32: