Sentence:  A Perſon of Honour, of a full Body abounding with ſharp Humours, was ſeized with an "Herpes" on his right Leg. ... [I]t inflamed and ſwelled very much, many Wheals aroſe, and <WSD>fretted</WSD> one into another, with great Excoriation. 
Meaning of the word marked with <WSD> tags:  To chafe or irritate; to worry.