Sentence:  On the other hand I heard only recently of a modern marvel — an organ of two manuals and about sixteen or eighteen stops with adequate and modern <WSD>mechanicals</WSD> that the pastor assures me has not been touched by repairer or even by tuner in four years! 
Meaning of the word marked with <WSD> tags:  A stop on an organ that is operated by a hand or foot control rather than having to be manually set up in advance.