Sentence:  Tis hard to say, how much these Arse-wormes do urge us, We now need no <WSD>Quack</WSD> but these Jacks for to purge us, [...] 
Meaning of the word marked with <WSD> tags:  (doctor) A fraudulent healer or incompetent professional; especially, a doctor of medicine who makes false diagnoses or inappropriate treatment; an impostor who claims to have qualifications to practice medicine. (from "c." 1630)