paraffin vs paraffin series

paraffin

verb
  • To impregnate or treat with paraffin. 

  • To embed in paraffin wax. 

noun
  • A petroleum-based thin and colourless fuel oil. 

  • paraffin wax. 

  • Any member of the alkane hydrocarbons. 

paraffin series

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