The increasing volume of work out of St. Louis headquarters required the active services of approximately fifty operatives, most of whom had abandoned their personal pursuits and were giving their entire time to the work of the League. In addition, two hundred and fifty men in the district organization were being called upon, more or less regularly, to undertake active investigations with respect to matters arising in their respective neighborhoods. The personnel of the organization was made up of loyal and self-sacrificing citizens in all walks of life. Much excellent service was rendered in investigations made at night by those who were unable to devote other time to the work. Each man did what he could. Cases of intense and varying interest were arising daily to sustain the zeal of this large body of volunteers. One of the most interesting involved a letter, mailed in St. Louis March 17, 1917, to “Mr. W. Bernkong, Berlin, Germany,” which found its way into the St. Louis headquarters and which appeared to be a code letter written in Greek characters and words. An inspection of this, and a close following through of the case in all the hands it reached, will give a reader some idea of the uncanny sureness of the United States government experts in deciphering any sort of blind communication that may come before them. The average unskilled person could make little out of the original letter, which was worse than Greek. Interest in this puzzle deepened when it was discovered that, although written in Greek characters, Greek scholars to whom it was submitted were unable to translate it. It was ultimately sent to the War College in Washington, that House of Mystery, which in due time returned a German translation, revealing the fact that Greek letters had been adapted to the formation of German words. It might still have remained possible for the real secret of the letter to have been concealed in an unknown code—as one may learn by reference to the brief mention of ciphers and codes in an earlier chapter (See “Arts of the Operatives”). Therefore, a first-class mystery story, indeed the best detective story of all those the League chiefs have sent in, still remains for any wise doctor who can solve it. It is easier to write a “detective story” than it is to read a cipher and double code, because a story-writer knows his own answer, whereas in the other case, no one knows the real answer.