There are four possible forms of election: scrutinium, compromissum, accessus, quasi-inspiratio. The usual form is that of scrutinium, or secret ballot, and in it the successful candidate requires a two-thirds vote exclusive of his own. When there is a close vote, and only then, the ballot of the pope-elect, which, like all the others, is distinguishable by a text of Scripture written on one of its outside folds, is opened to make sure that he did not vote for himself. Each cardinal deposits his vote in the chalice on the altar and at the same time takes the prescribed oath: "Testor Christum Dominum qui me judicaturus est me eligere quem secundum Deum judice eligi debere et quod idem in accessu præstabo"—"I call to witness the Lord Christ, Who will be my judge, that I am electing the one whom according to God I think ought to be elected", etc. (For the form of the oath see Lucius Lector, "Le Conclave", 615, 618.) The ballot reads: "Ego, Cardinalis N., eligo in summum Pontificem R. D. meum D. Card. N."
For this election by secret ballot three cardinals (scrutatores) are chosen by lot each time to preside over the operation of voting, three others (revisores) to control the count of their colleagues, and still three others (infirmarii) to collect the ballots of the sick and absent cardinals. If the sick cardinals cannot attend the balloting, then the three infirmarii go to their cells and bring back their votes in a box to the three cardinals presiding, who count them and put them in the chalice with the others. Then, all the ballots having been shaken up and counted, if the number agrees with the number of electors, the chalice is brought to the table and the ballots, on the outside of which appear the names of the candidates, are passed from hand to hand to the third cardinal who reads the names aloud. All present are provided with lists on which the names of all the cardinals appear, and it is customary for the cardinals to check off the votes as they are read. Then the three cardinal revisors verify the result which is proclaimed as definite.
If, upon the first ballot, no candidate receives the necessary two-thirds vote, recourse is often had to the form of voting known as accessus. At the election of Pius X (Rev. des Deux Mondes, 15 March, 1904, p. 275) the cardinal dean did not allow the accessus, though it is a recognized usage of conclaves, regulated by Gregory XI, designed primarily to hasten elections, and usually considered to favour the chances of the candidate who has the most votes. It consists practically of a second ballot. All use the ordinary blanks again, with this difference, that if the elector wishes his vote to count for his first choice he writes Accedo nomini; if he changes his vote he introduces the name of his latest choice. Then the two series of ballots have to be compared and identified by the text on the reverse face of the ballot, so as to prevent a double vote for the same candidate by any elector. When the required two-thirds are not obtained, the ballots are consumed in a stove whose chimney extends through a window of the Sistine Chapel. When there is no election, straw is mixed with the ballots to show by its thick smoke (sfumata) to those waiting outside that there has been no election. There are always two votes taken every day, in the morning and in the evening; they occupy from two to three hours each. When the voting is over one of the cardinals opens the door outside of which are gathered the conclavists, and all retire to their cells. Other forms of election, made almost impossible by the legislation of Gregory XV, are known as quasi-inspiration and compromise. The former supposes that before a given session there had been no agreement among the cardinals and that then one of the cardinals, addressing the assembly, proposes the name of a candidate with the words Ego eligo (I elect, etc.), whereupon all the cardinals, as though moved by the Holy Spirit, proclaim aloud the same candidate, saying Ego eligo, etc. An election by compromise supposes that after a long and hopeless contest the cardinals unanimously delegate a certain number of their body to make a choice. It has not been employed since the fourteenth century.
When a candidate has obtained the required two-thirds vote in a scrutiny or ballot (the choice, since Adrian VI, 1522, falling on one present and invariably on an Italian cardinal), the cardinal dean proceeds to ask him whether he will accept the election and by what name he wishes to be known.