"Well, I thought it might be useful to ascertain all these dates exactly, and, in order to do that, it would be necessary to take transcripts from the parish register at S. Saviour's. I wrote to Chalmers, and asked him to look up this information and bring it with him when he came to Stockbridge. Not only did he do this, but he took the trouble to type out the complete record, so that all the facts in the case might lie under the eye. I'll read it." Betty pulled out a folded sheet of paper from the portfolio lying in her lap and began: Yardley Hildebrand, b. March 5, 1806; succeeded his father, Oliver, 1860; d. June 20, 1861. Randall Hildebrand, b. May 11, 1809; succeeded his brother, Yardley, 1861; d. June 22, 1862. Horace Hildebrand, elder son of Randall, b. December 4, 1830; succeeded his father, 1862; d. June 22, 1865. Richard Hildebrand, younger son of Randall, b. June 1, 1835; succeeded his elder brother, 1865; d. June 20, 1918. Francis Hildebrand Graeme, great-nephew to Richard, b. April 13, 1874; succeeded his great-uncle, 1918; d. June 21, 1919. Eunice Trevor, b. September 2, 1892; d. June 20, 1920. "And now we may add a final entry," continued Betty: "John Thaneford, nephew to Richard, b. July 16, 1892; d. June 22, 1922." Betty handed me over the list. "Do you notice anything peculiar about those dates?" she asked. I read the paper through, and then again. "You have already pointed out," I began hesitatingly, "that the tenure of 'Hildebrand Hundred' was for the comparatively brief period of one to three years. Except for Richard, who held the property for over fifty." "I don't mean that. Examine the actual dates." I scanned the record with still greater attention. "Ah!" I exclaimed, "here _is_ something strange. Everyone of these men, and Eunice, too, died in June; yes, and on a day of the month that varied between the twentieth and the twenty-second. Is that what you had in mind?" "Yes, and it seemed to indicate clearly that those particular three days, the twentieth, twenty-first, and twenty-second of June----" "In astronomical parlance, the summer solstice," interrupted Warriner. "----was the danger period." "Yes, and then?" "Your letter came, saying that you had been obliged to enter the library to look after the window repairs; you added that you would probably have to go again to finish up the job. As I have already told you, that letter reached me on Thursday morning, June the twenty-first; Chalmers and I left at once for New York. On the way down I succeeded in reading the cypher, and so got Fielding Thaneford's message in full." "But how in the world----" I began. "You'll know in good time," cut in Betty. "First, I want you to consider another of my sources of information. Here it is," and she held up a small book bound in tattered leather.