In later times the custom was reversed; the altar was no longer reared over the bones of the saint, but the body of anyone whom the church specially wished to honour was buried beneath the altar; and even now, when interments within churches are forbidden, the same natural feeling often finds expression in the burial of a parish priest immediately without the east wall, as near as possible to the altar that he served. Probably it was the thought of security guaranteed by the sacredness of the altar which suggested to the monks of Canterbury the making of a grated vault beneath the high altar of the cathedral, in which to store their treasures. Here, before the Reformation, was kept a collection of gold and silver vessels, so large and costly, that in the opinion of Erasmus, Midas and Croesus would seem but beggars in presence of it. This altar was itself lavishly adorned, and all its glory had not disappeared in the days of Archbishop Laud, one of whose offences was the adorning of it with "a most idolatrous costly glory cloth." For richness of material no altar that the world has seen could well excel the one erected in the Cathedral of S. Sophia by the Emperor Justinian. It was "a most inimitable work, for it was artificially composed of all sorts of materials that either the earth or the sea could afford, gold, silver, and all kinds of stones, wood, metals, and other things; which being melted and mixed together, a most curious table was framed out of this universal mass." The result, one cannot but think, with all its splendour, must have been somewhat barbaric. Other altars we read of in the early ages made of gold, or of pure silver, and others, like that presented to a church by Pulcheria according to Sozomen, adorned with gold and precious stones. There seems never to have been any very definite rule in force as to the material of which an altar should be made. It is true that the Council of Epaone (A.D. 517) decreed that "no altar should be consecrated except it were of stone;" but in practice, metal and wooden altars still continued to be used, both in the east and the west. The custom of having a tabernacle permanently on the altar for the reservation of the Blessed Sacrament did not become usual until the twelfth century, but as early as the middle of the ninth century, Leo IV. mentions a pyx suspended for the same purpose above it. In fact we find traces as far back as the sixth of the use of pyxes in the form of doves made of gold or silver; and in England this custom continued until the Reformation. The pyx at Durham Cathedral, which hung from a hook still to be seen in the roof, was in the form of a pelican "in her piety," that is, feeding her young with her heart's blood; a figure which has been copied in the lectern now in use.