The early Christian altars were portable structures of wood, and the Church of Rome still allows the use of an altar of this description, although a consecrated stone, containing an authentic relic and regarded as the true altar, must be placed upon the wooden table. The slab forming the altar was sometimes supported on pillars, but more frequently on solid masonry, and previous to the Reformation it was marked with five crosses cut into the top, in allusion to the five wounds of Christ. From the period that stone altars were introduced it was usual to enclose within them the relics of saints, so that in some cases they were the actual tombs of saints. In England the altars were generally taken down about the year 1550, set up again in the beginning of the reign of Queen Mary, and again removed in the second year of Queen Elizabeth. In the church of Porlock, Somerset, the original high altar has been preserved, though not in use, being placed against the north wall of the chancel. In Dunster Church, in the same county, there is a solid stone altar, said to have been the original high altar, and in the ruined church of S. Mary Magdalene at Ripon, the high altar has escaped destruction. Of chantry altars we have several left, including those at Abbey Dore, Herefordshire; Grosmont, Monmouthshire; Chipping Norton, Oxon.; Warmington, Warwick; S. Giles's, Oxford; Lincoln Cathedral, and many others; and it is rare to find a Gothic church without some traces of altars in their various chapels, oratories or chantries. The altar is, of course, an adoption by the Christian church of a pagan aid to worship, and at S. Mary's church, Wareham, which is thought to stand on the site of a Roman temple, are some pieces of stone considered by antiquaries to be portions of a pagan altar, on which burnt offerings were placed. Above many Christian altars was placed a piece of sculpture or a painting representing some religious subject. These altar pieces sometimes consist of two pictures, when they are called "diptyches," and sometimes of three pictures, when they are called "triptyches," and both forms usually fold up or are provided with shutters. They are often rare examples of the Flemish and other schools of painting, and of great value. At the Reformation the stone altar was displaced by the communion table, which at first occupied the position vacated by the altar. This gave umbrage to the Puritan mind, and the communion table was then usually placed in the centre of the chancel, with seats all round for the communicants; which arrangement is still in vogue in some of our English churches and in Jersey, although at the Restoration the communion table was, as a general rule, replaced at the eastern wall of the Chancel. [Illustration: _Durham Sanctuary Knocker._]