Modes of Contracting Marriage with Manus
There were three modes of contracting marriage with manus:
(1) Confarreatio. This was a religious rite the precise form of which has not come down to us. It consisted essentially in the sacrifice of wheaten bread {farreus panis) to Jupiter. (Compare the modern wedding cake.) The ceremony took place before the Pontifex IMaximus and the priest of Jupiter. Only patricians could marry by this mode, and only persons born of this kind of marriage were eligible to the priestly office. (Gains, I, § 112.)
(2) Coemptio. This was a purchase of the wife by the husband from the person in whose power she was. The transaction was by the ceremony of mancipation, in the presence of the balance-holder and five witnesses. Coemptio was the ordinary form in which any Roman citizen, whether patrician or plebeian, might marry. (Gaius, I, § 113.)
(3) Usus. Where a man and a woman not married by either of the above modes cohabited as husband and wafe for a period of one year, their, marriage, previously resting upon mere consent (free marriage), ripened into the strict marriage by prescription and the wife passed in manum. But the Twelve Tables provided that the wife might avoid this result by absenting herself for three consecutive (Roby, 69) nights in each year, thus interrupting the tisus for that year. (Gains, I, § 111.)