Sentence:  … as he beheld the tenfold pirouette of a lovely girl, which presented to the public eye the whole of her form and figure; … to praise the dexterity and ease with which the unfortunate and degraded creature had performed the ungraceful <WSD>evolution</WSD>, the only merit of which, is the gross exposition of person, at which modesty shudders […] 
Meaning of the word marked with <WSD> tags:  A turning movement of the body.