bath sponge vs sea sponge

bath sponge

noun
  • A sponge, made from any material, that is used for cleaning the body while bathing. 

  • A commercially used species of sponge (porifer, invertebrate of the phylum Porifera) found throughout the Mediterranean Sea, Spongia officinalis. 

sea sponge

noun
  • sponge (animal, Porifera) 

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