It will be observed that the royal charters which authorise the Gilds and grant exclusive privileges of trading differ somewhat in later years from those of the earliest date. In the earliest grants the words simply allude to the Gild only. Henry II.'s Charter to Lincoln is "Sciatis me concessisse civibus meis Lincolniae ... gildam suam mercatoriam." There is no hint of any tradesmen external to the Gild. But early in the thirteenth century it becomes evident that such stringent exclusiveness could not be enforced. The charter which Henry III. granted to Shrewsbury in 1227 confirmed the Gild in the following terms:--"Concessimus etiam eisdem Burgensibus et heredibus eorum quod habeant Gildam Mercatoriam cum Hansa et aliis consuetudinibus et libertatibus ad Gildam illam pertinentibus, et quod nullus qui non sit in Gilda ilia mercandisam aliquam faciat in predicto Burgo _nisi de voluntate eorundem Burgensium_." At about the same time the Earl of Chester and Huntingdon gave a charter to Chester forbidding trade in the town "nisi ipsi cives mei Cestrie et eorum heredes _vel per eorum gratum_." The phrase "nisi de voluntate eorundem Burgensium (or Civium)" now became usual in the charters. In those granted by Edward I. to the towns which he founded in Wales, and which may be looked upon in some measure as model town constitutions, the provision appears in each. Thus it may be said that by the end of the thirteenth century it had become customary for the town authorities to grant exemptions from the Gild restrictions by their own authority. They practically gave over to the Gilds the supervision of trade, but at the same time retained in their own hands the power of admitting traders without obliging them to join the mercantile fraternities. This power of granting exemptions from the restrictions of the Gilds seems to have been exercised in various towns in different degrees. In some it extended no further than the permitting "foreigners" to come to casual markets on payment of a toll upon each occasion. In others however it was more largely and generally used, merchants being allowed to be resident and to trade continually and regularly by payment of an annual fine.