bibcock vs floodgate

bibcock

noun
  • An appliance (typically a valve with a threaded outlet) allowing the provision of hose connections outside of buildings. 

floodgate

noun
  • An adjustable gate or valve used to control the flow of water through a sluice. 

  • Anything that controls or limits an outpouring of people, emotion etc. 

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