fibreglass vs magnifying glass

fibreglass

noun
  • A composite material made from fine fibres of spun glass held together with resin. 

  • Silica based glass extruded into fibers that possess a length at least 1000 times greater than their width. 

verb
  • To apply fibreglass to. 

magnifying glass

noun
  • An instrument made of convex glass, used to magnify. 

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