crackers vs doolally tap

crackers

adj

  • Crazy, insane. 

noun

  • A kind of noisy leather pants or trousers. 

doolally tap

adj

  • Mad, insane, eccentric. 

noun

  • Camp fever; by extension, madness, eccentricity. 

How often have the words crackers and doolally tap occurred in a corpus of books? (source: Google Ngram Viewer )