 Complete the following phrase:  The seals of the signatories to the letter survive in excellent condition. Although they are now detached from the document, they form the earliest contemporary group of true coats of arms, the rules of heraldry having only been established at around the start of the 13th century, and were stated for that reason by Lord Howard de Walden to be of very great value to students of heraldry. Many of the armorials also appear in the near contemporary Falkirk Roll of Arms made before the 