broker vs travelling salesman

broker

noun
  • A mediator between a buyer and seller. 

  • An agent involved in the exchange of messages or transactions. 

  • A stockbroker. 

  • A mediator in general, one who liaises between two or more parties to attempt to achieve an outcome of some kind. 

verb
  • To act as a broker; to mediate in a sale or transaction. 

  • To act as a broker in; to arrange or negotiate. 

travelling salesman

noun
  • A man who travels, often within a certain territory, soliciting orders or selling goods. 

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