person booking up a room for the following mid-day either to book earlier or leave it till the morning of the day itself? What was the urgency? There are plenty of hotels in Seabourne. No—I formed my first main conclusion although I didn’t give it away and considered it carefully more than once afterwards. _The idea was to hide the identity of Sheila and inasmuch as the stolen suit-case belonged to Daphne Carruthers—the dead girl would be supposed to be Daphne Carruthers for a time at least—therefore at ten-fifty the room was booked in that particular name._ Do you follow me?” “Excellent, Mr. Bathurst,” contributed Sir Austin, “sound reasoning.” “And yet Daphne was the very girl about whom _the blackmailing process had been_. Strange wasn’t it? The Crown Prince had no knowledge of Sheila! Why was Sheila dead? Why did the murderer want _time_? But there was this point. I began to think very seriously about the group of people staying at the ‘Cassandra’—_the hotel from which the suit-case had been stolen_. Consider who they were! The Crown Prince, Daphne herself, a Captain Willoughby who knew most of them—_and Chief-Inspector Bannister_. He was there—you see—right in the circle of suspicion. The next stage was at Tranfield. Bannister went up—I went with him—Tranfield interested me—from more than one point of view. We discovered that the car that took Sheila to Seabourne had been driven back to her home at Tranfield. There was actually a Seabourne newspaper in it. Why had it been driven back? The answer was easy. The house had been searched for something—what it was I will tell you later. It was here that Sheila Delaney’s old lover—Alan Warburton came into my calculations. Here, at any rate, was a motive. The jilted lover—jealousy—ample motive, if you think it over. But a new aspect of the case struck me and just as I was considering it—I made a find. In Sheila’s bedroom I found a postcard. Just an ordinary postcard perhaps—the message I may describe as horticultural and amatory—it was signed ‘X.’ But it contained the word ‘irides’—the true Greek plural of ‘iris.’ Now ninety-nine people out of a hundred say ‘irises’ when they speak of more than one ‘iris.’ Our unknown correspondent however was meticulous concerning his plurals. _So had been Bannister!_ More than once he had used ‘maxima’ to me in conversation and I had been particularly struck with the fact that he used the word ‘data’ as a plural—with a plural verb—quite correctly. But nearly everybody uses ‘data’ as a singular noun and with a singular verb. People say ‘data helps’ not ‘data help.’ I rubbed my hands—I’m afraid it’s a habit of mine when I begin to ‘get hold.’ Yes—Bannister was particularly precise about his plurals.” “Wonderful, Bathurst,” intervened Sir Austin, “a touch of genius—that. He was a Dulwich boy—you know.”