Edward Thomason registered his mark some time between 1803 and 1807.  Jackson records work of his in 1817 and 1828.  These tongs are dated 1813/14 and are very plain and un-remarkable.  One curious feature of these tongs is that they are marked with the clipped duty mark.  Jackson records that this mark has been replaced by a full oval duty mark by 1812.  Clearly they were still using the clipped duty mark for some time after this.