London: various 1882-1923. The collection offered here includes two offprints, one early pamphlet, and a signed letter from Kingsbury to his son on a Turkish telephone company letterhead.
1) J. E. K. [ Kingsbury, John Edmund ]. The Telephone in Principle and Practice: Its Origin and Development. London: David Bogue, 1882. First Edition. , 39, [1,blank] pages. 8vo (5 1/2 x 8 3/8 inches). Light blue stapled wraps. Rear wrapper lacking (advertisements, we provide a printout of another copy for reference), spine taped with cellotape (fragile thus with binding loose). Penciled notes on half-title identifying Kingsbury and noting it is his first work (not independently confirmed). Good. Wraps. An early discussion of the telephone. There were 10 copies of this pamphlet in OCLC as of this writing. 
2) Kingsbury, J. E. [ John Edmund ]. The Future of the Telephone in the United Kingdom: Paper read before Section G of the British Association for the Advancement of Science, at Belfast, September 15, 1902. London: George Tucker, 1902. First Separate Edition. -16 pages. 8vo (5 1/2 x 8 3/8 inches). Light brown stapled wraps. Light soiling overall. An offprint from the Electrician, September 26, 1902. Occasional penciled line in the margins highlighting passages. Spine is worn and split bottom two inches. Near Fine. Wraps. This story was Paper read before Section G of the British Association for the Advancement of Science, at Belfast, September 15, 1902. There were no copies of this offprint in OCLC as of this writing. 
3) Kingsbury, J. E. [ John Edmund ]. The Story of the Telephone. London: The Electrician Printing and Publishing Co. Ltd., 1916. First Separate Edition. -11 pages. 8vo (5 1/2 x 8 3/8 inches). Tan stapled wraps. Light soiling overall. An offprint from the Electrician, September 15, 1916. Near Fine. Wraps. This story was "contributed to the special number of 'The Electrician' commemorating its 200th issue" and is a more personal narrative discussing some of his experiences including being at the earliest international telephone test between London and Calais. He was "on the Edison side" and talks about some of the issues confronting early adopters. There were no copies of this offprint in OCLC as of this writing. 
4) Kingsbury, J. E. [ John Edmund ]. Autographed letter signed from John E. Kingsbury to his son Harold. Turkey: Constantinople Telephone Company, 1923.
An autographed letter signed from telephony historian and participant John E. Kingsbury to his son Harold on "The Constantinople Telephone Company" letterhead:
18 June 1923
My dear Harold:
I was very glad to get yours of 13th this morning. I arrived here on my return from Angora lake y'day afternoon. I shall have something to tell you about the journey when I come back. Just when that will be I cannot say but I shall leave this week I hope. I may however have to break the journey at Paris for a day or so. I am more than sorry at not being home by the 23rd + have written Marjorie to say so.
My best love to mother & all Your loving Father
J. E. Kingsbury"
Folded for mailing, a few edge tears and one fold is torn several inches. No loss of content. Verso is blank. Printed letterhead notes return address should read: "Box 36, British Post Office". Near Fine. Wraps. . 
John E. Kingsbury is best known to collectors for his book "The Telephone and Telephone Exchanges Their Invention and Development" published in London in 1915. That work was termed by Shiers/Sterling ""An important and detailed technical history, with emphasis on British and European developments." (see Origins of Cyberspace #170)
Kingsbury traveled extensively and was involved in the telephone trade from an early age. He was instrumental in the development and deployment of the telephone in London (see Power of Speech by Peter Young for an extensive discussion of his involvement). Letters and early material by Kingsbury are hard to find.
None of these items were found in Sterling/Shiers (History of Telecommunications Technology, An Annotated Bibliography: Scarecrow Press, 2000)