A further, though rather sad, interest attaches to the McGowan story, for only a short time had elapsed after his return to America when he disappeared suddenly and mysteriously, and in spite of long-continued and strenuous efforts to obtain some light on the subject, no clew or trace of him was ever found. He was a favorite among the Edison "oldtimers," and his memory is still cherished, for when some of the "boys" happen to get together, as they occasionally do, some one is almost sure to "wonder what became of poor 'Mac.'" He was last seen at Mouquin's famous old French restaurant on Fulton Street, New York, where he lunched with one of the authors of this book and the late Luther Stieringer. He sat with them for two or three hours discussing his wonderful trip, and telling some fascinating stories of adventure. Then the party separated at the Ann Street door of the restaurant, after making plans to secure the narrative in more detailed form for subsequent use--and McGowan has not been seen from that hour to this. The trail of the explorer was more instantly lost in New York than in the vast recesses of the Amazon swamps. The next and last explorer whom Edison sent out in search of natural fibres was Mr. James Ricalton, of Maplewood, New Jersey, a school-principal, a well-known traveller, and an ardent student of natural science. Mr. Ricalton's own story of his memorable expedition is so interesting as to be worthy of repetition here: "A village schoolmaster is not unaccustomed to door-rappings; for the steps of belligerent mothers are often thitherward bent seeking redress for conjured wrongs to their darling boobies. "It was a bewildering moment, therefore, to the Maplewood teacher when, in answering a rap at the door one afternoon, he found, instead of an irate mother, a messenger from the laboratory of the world's greatest inventor bearing a letter requesting an audience a few hours later. "Being the teacher to whom reference is made, I am now quite willing to confess that for the remainder of that afternoon, less than a problem in Euclid would have been sufficient to disqualify me for the remaining scholastic duties of the hour. I felt it, of course, to be no small honor for a humble teacher to be called to the sanctum of Thomas A. Edison. The letter, however, gave no intimation of the nature of the object for which I had been invited to appear before Mr. Edison....