The age of twenty-one has been fixed by the law for centuries as that at which either a man or woman is regarded by the law as acquiring full capacity52 No distinction generally has been drawn so far as concerns contractual capacity between a minor of tender years and one, who, having nearly attained his majority, has ample intelligence in fact.53 As the law disregards for many purposes fractions of a day, an infant becomes of age at the beginning of the day preceding the twenty-first anniversary of his birth.54 The rules of the common law in regard to the duration of infancy still prevail unless altered by statute. By such statutes in many States a woman becomes of age at eighteen,55 and in a few an infant becomes of age on his birthday and not on the preceding day.56 Not infrequently the marriage of a female infant is given by statute the effect of making her of full contractual capacity,57 and in a few States the marriage of either man or woman under the age of twenty-one years has the effect not only of emancipation, but of giving full contractual capacity.58

47See Rolle's Abr. "Enfants"; Bacon's Abr. "Infancy" and Comyns Digest "Enfant," for a collection of these cases.

48 Profitable Book, Sec. 12.

49 This was so decided by Lord Mansfield in Zouch v. Parsons, 3 Burr. 1794. As to modern authorities, see infra, Sec.227.

50 See infra, Sec. 227.

51Keane v. Boycott, 2 E. Bl. 611, 516; Harvey v. Ashley, 3 Atkins, 607; Earl of Buckinghamshire v. Drury, 2 Eden, 60, 72; Grey v. Cooper, 3 Doug. 65.

52 2 Pollock & Maitland Hist. 438, Co. Litt. 171; 1 Bl. Com. 463.

53 Ex parte McFerren, 184 Ala. 223, 63 So. 159, 47 L. R. A. (N. S.) 543; McCarty v. Carter, 49 111. 53, 95 Am. Dec. 572; Baker v. Lovett, 6 Mass. 78, 4 Am. Dec. 88; and see cases on infancy cited in this section, possim. In California and North Dakota by statute a minor above the age of eighteen cannot disaffirm a contract without restoring the consideration. Hakes Inv. Co. v. Lyon, 166 Cal. 557,137 Pac 911; Casement v. Callaghan, 35 N. Dak. 27, 159 N. W. 77.