bateau vs coracle

bateau

noun
  • A small, flat-bottomed type of boat. 

coracle

noun
  • A small circular or oblong boat made of wickerwork and made watertight with hides or pitch, propelled and steered with a single paddle and light enough to be carried on a person's back. 

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