assay vs indubitability

assay

noun
  • Tested purity or value. 

  • Trial, attempt. 

  • The qualitative or quantitative chemical analysis of something. 

  • The act or process of ascertaining the proportion of a particular metal in an ore or alloy; especially, the determination of the proportion of gold or silver in bullion or coin. 

  • The alloy or metal to be assayed. 

  • Examination and determination; test. 

  • Trial by danger or by affliction; adventure; risk; hardship; state of being tried. 

verb
  • To affect. 

  • To analyze or estimate the composition or value of (a metal, ore etc.). 

  • To attempt (something). 

  • To try tasting, as food or drink. 

indubitability

noun
  • The quality or state of being indubitable. 

  • Something that cannot be doubted; a certainty. 

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