Sentence:  [I]t is sufficiently evident from the physiology of man, that boils and eruptions cannot be produced in perfectly healthy persons through the action of water, since water is a matter the most conceivably mild, and since boils produce a feeling always painful, and more or less <WSD>acrimonious</WSD> and corrosive, which can only be caused by acrid corrosive matters, or by biting animalculae which form the boil. 
Meaning of the word marked with <WSD> tags:  Harsh and sharp, or bitter and not pleasant to the taste; acrid, pungent.