Welsh cat vs mog

Welsh cat

noun
  • Synonym of cat (sense 10, a wheeled shelter) 

mog

noun
  • Synonym of moggy: a domestic cat, especially a non-pedigree or unremarkable one. 

verb
  • To assert one's dominance over. 

  • To move away; to go off. 

  • To pass better than someone. 

How often have the words Welsh cat and mog occurred in a corpus of books? (source: Google Ngram Viewer )