Sentence:  John, however, howsoever inconsistent in his farming, was never so with respect to his character; having always and avowedly piqued himself more on his knack at <WSD>ambidextry</WSD>, than congruity or discernment; and frequently, while in times of scarcity and dearth, he with one hand supplicates in his churches the Author of all good gifts for plenty and cheapness, he with the other takes care to prevent their possibility, by withholding in various ways their means, and not giving the plough free admission to his immense tracts of wastes, nor withdrawing it from those of aration till they are completely exhausted of all the fertilizing gifts of heaven; he thus renders them both comparatively useless. 
Meaning of the word marked with <WSD> tags:  Two-sidedness; Embracing or engaging in both sides of a dichotomy.