Respectfully Quoted: A Dictionary of Quotations. 1989.
Michael Faraday (17911867)
Mr. Gladstone, then Chancellor of the Exchequer, had interrupted him in a description of his work on electricity to put the impatient inquiry: But, after all, what use is it? Like a flash of lightning came the response: Why, sir, there is every probability that you will soon be able to tax it!
MICHAEL FARADAY.James Kendall, Michael Faraday, Man of Simplicity, Introduction, p. 14 (1955).