radiotelegraph vs telephony

radiotelegraph

noun

  • wireless telegraphy 

verb

  • To communicate or transmit by wireless telegraphy. 

telephony

noun

  • The study and application of telephone technology. 

  • The act of sound transmission via the electromagnetic spectrum. 

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