One page autograph letter dated 14 November, 1914, addressed “Dear Matz,” and signed “Yours very sincerely, T. W. Tyrell.”  The letter reads: “Enclosed is the portrait for which you ask.  I had forgotten that I am mentioned in Mr. Eckel’s Bibliography, and not seeing my name in the index had some difficulty in finding the reference.”  One can surmise, based on the content of this letter, that Matz collaborated with John Patterson in the latter’s efforts to extra-illustrate the Eckel Bibliography.