crofting vs refinement

crofting

noun
  • The process of exposing linen to the sun, on the grass, in the process of bleaching. 

  • A form of land tenure and small-scale food production, unique to the Highlands and islands of Scotland, in which individual crofts are established on the better land while a large area of poor-quality hill ground is shared by all the crofters of the township for grazing. 

refinement

noun
  • The act, or the result of refining; the removal of impurities, or a purified material 

  • A fine or subtle distinction. 

  • High-class style; cultivation. 

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