I'll be a dirty bird! vs by Allah

I'll be a dirty bird!

by Allah

intj

  • An exclamation of surprise or excitement, oh my God! good Lord! 

adv

  • An oath to emphasize sincerity or truthfulness, by God 

  • Very, truly, indeed. 

How often have the words I'll be a dirty bird! and by Allah occurred in a corpus of books? (source: Google Ngram Viewer )