After graduating from Cornell, Miller worked for a time in the US Patent Office as an examiner. In 1897, he found employment at Westinghouse Electric and Manufacturing, but left after only months to work as an electrical engineer for the Western Telephone Construction Company in Chicago as chief electrician. Starting in 1898, he began a career as book author in telephony and telegraphy, and contributing and editing correspondence school text books. In 1899, he published his seminal work
American Telephone Practice, and became electrical engineer at the
Kellogg Switchboard & Supply Company, quickly ascending to lead the experimental shop and laboratory. At Kellogg he was an unwitting accomplice to the secret takeover by the
Bell Telephone Company, reversed after a lawsuit by the company's founder, Milo G. Kellogg. He then formed an engineering consulting firm with Samuel G. McMeen in 1904 in
Chicago, Illinois, a partnership he maintained until 1919, when he became manager of the North Electric Manufacturing Company. After 1922, he returned to consulting and wrote numerous papers and treatise in telephony technology.
American Telephone Practice In 1899, the American Electrician Company published Miller's book,
American Telephone Practice. At 458 pages including many dozens of illustrations, it detailed nearly everything known about telephone technology at the time. Two more editions followed within one year in 1900. In 1905, a final edition, the fourth, was published by McGraw-Hill Book Company. The edition, "
enlarged and entirely rewritten", grew to 888 pages. ==Philanthropy==