Besides all the precautions taken to render any substitution impossible, we may add that Baldwin, on being required to examine and identify the relic, declared its authenticity in a document written on parchment, which was in existence until the Revolution of 1793, signed with his own hand in Greek characters, traced in cinnabar, and having his own seal, of lead covered with gold, affixed. On one side of this seal the emperor was represented enthroned, with the inscription: “_Balduinus Imperator Romaniæ semper Augustus_.” On the other he was on horseback, with the inscription in Greek letters: “_Baudoin, Empereur, Comte de Flandre_.” It must also be borne in mind that the Venetians, before lending so considerable a sum for such a pledge, would be certain to satisfy themselves beyond all doubt as to its authenticity, and that, even had he been so minded, Baldwin could not in this matter have imposed upon the credulity of St. Louis, as some modern writers have asserted, but that he did really receive that which the whole Christian world regarded as the crown of thorns of our Lord Jesus Christ. Still, some additional proof may be required, and for this we must go back to an earlier period. We must also consider the nature of this crown; for many churches affirm, and with good reasons, that they possess thorns or fragments of the same, and yet these portions frequently do not resemble that which is at Paris. In the first place, it is certain that a century and a half before the reign of St. Louis, at the time of the First Crusade, all the world admitted that a very large portion of the crown was preserved at Constantinople, in the chapel of the Greek emperors. When Alexis Comnenus wished to induce the Christian princes to go to his assistance, he spoke to them of the very precious relics which they would help to save, amongst which he especially designated the crown of thorns. Also, in the time of Charlemagne, all the West had the certainty that Constantinople possessed this treasure, of which a considerable part was equally known to be at Jerusalem. Towards the year 800, according to Aimoin, the Patriarch of Jerusalem had detached some of the thorns, which he sent to Charlemagne, who deposited them at Aix-la-Chapelle with one of the nails of the true cross, and it was these relics which were afterwards given by Charles le Chauve to the Abbey of St. Denis. The existence of the crown is a fact constantly alluded to in the sixth century, by St. Gregory of Tours amongst others; and about the year 409 St. Paulinus of Nola knew of its preservation. He writes: “The thorns with which the Saviour was crowned, and the other relics of his Passion, recall to us the living remembrance of his presence.”