His brain was on fire. He thought of everything. Furstenheimer had been a trailing sleuth. He had fooled Kirtley completely. It was a masterly piece of work. Gard metaphorically took off his hat to the German Secret Service. Notwithstanding the Jim Deming episode and Anderson's animadversions, this had been a highly expert demonstration of the art. Gard's mind went over his whole trip from Eisenach, trying to find where his suspicions should have been more aroused. He could discover no loophole where any unflattering dullness on his part was particularly at fault. He had made rather the most advances at Cologne to the self-styled Furstenheimer with his Roman horse. How casually, too, the two confederates had been picked up at the cathedral! Their intelligent interest in stained glass! Very clever. All had been wonderfully clever. He now saw that when Furstenheimer left him at Cologne to decide about joining him, and also when the three had gone off to inspect the windows, there had been ample time to perfect their scheme. His passport! What on earth could they want of that! In the German way they had used a steam hammer to crack a hickory nut. No one in 1914 had an inkling of what service American passports were to be to the Kaiser's Government. The world was soon to rub its eyes over Germany's treacherous, fiendish, employment of chemicals both on documents and on humans. Lackadaisical mankind did not then dream of the thoroughness and elaboration with which Deutschland was preparing her many deep and diabolical designs. Toward dawn Gard, pretty well winded and in a bath of perspiration, trudged along more slowly while his thoughts streamed precipitately ahead under the pressure of the stupefying developments. He now knew who the little German was. He was that rigid, whiskered, military person in the train from Eisenach! The same flat, wide-lobed nose. He had not guessed it before because the face, clear of a beard, had really suggested in Aix (he now realized) that of the typical shaven Teuton waiter. But why had the spy traveled in such a stiff and mysterious fashion? Likely to locate the passport--find out whether it was then being carried in the grip or on Kirtley's person. In some way--probably from the manner in which the grip had been handled--the sleuth had convinced himself it was kept in a pocket.