(7) _Burgage_, confined exclusively to lands within free boroughs, is mentioned as a separate tenure by Littleton,[76] and his authority receives support from the words of chapter 37 of Magna Carta. Our highest modern authorities,[77] however, consider that it never acquired sufficiently distinct characteristics to warrant its acknowledgment as such. They treat it rather as a special variety of socage, used where the tenants were the members of a corporation. If their opinion must be accepted for England, it follows that, from common antecedents, entirely different results have developed in Scotland and in England respectively. While, north of the Tweed, several of the well-established English tenures have failed to make good their right to separate recognition, burgage has established itself beyond a doubt. Even the levelling process consummated by the Conveyancing (Scotland) Act of 1874 has not entirely abolished its separate existence. ----- Footnote 76: _Ibid._, II. x. s. 162. Footnote 77: Pollock and Maitland, I. 218. ----- The explanation of such differences between English and Scottish usage easily suggests itself. When feudalism first took root, the various shades of distinction in the conditions of holding were exceedingly numerous, and merged into one another by imperceptible degrees. The work of definition came later, was essentially artificial in its nature, and assumed different forms in different lands.[78] ----- Footnote 78: Littleton and Coke seem almost to countenance two additional tenures, viz., tenure by scutage or escuage, and tenure by Castle-guard. Pollock and Maitland consider both as alternative names for knight’s service. (See I. 251 and I. 257.) The latter is discussed _infra_ under c. 29 of Magna Carta. ----- These tenures, originally six or seven (according as we exclude or include burgage), have yielded to the unifying pressure of many centuries. Frankalmoin and Grand Serjeanty still exist, but rather as ghosts than realities; the others have all been swallowed up in socage, which has thus become practically identical with “free-hold.”[79] This triumph of socage is the result of a long process. Fee-farm, burgage, and petty serjeanty, always possessing many features in common, were gradually assimilated in almost all respects, while a statute (12 Charles II. c. 24) transformed tenure in chivalry also into socage. The once humble socage has thus risen high, and now embraces most of the land of England.[80] ----- Footnote 79: Jenks, _Modern Land Law_, p. 14. Footnote 80: