Sentence:  Sir, as I said last time, labour to keep your alacrity and dignity, in an even temper: for in a dark sadness, indifferent things seem abominable, or necessary, being neither; as trees, and sheep, to melancholy night-walkers, have <WSD>unproper</WSD> shapes. 
Meaning of the word marked with <WSD> tags:  Improper, not according with fact or reason; wrong, irregular. (14th-17th c.)