The Layton Court Mystery by Anthony Berkeley

Roger sat through the first part of lunch in a species of minor trance. It was not until the necessity for consuming a large plateful of prunes and tapioca pudding, the two things besides Jews that he detested most in the world, began to impress itself upon his consciousness, that the power of connected thought returned to him. Mrs. Plant's revelation appeared temporarily to have numbed his brain. The one thing which remained dazzlingly clear to him was that if Stanworth had written a letter announcing his impending suicide, then Stanworth could not after all have been murdered; and the whole imposing structure which he, Roger, had erected, crumbled away into the sand upon which it had been founded. It was a disturbing reflection for one so blithely certain of himself as Roger.

As soon as lunch was over and the discussion regarding trains and the like at an end, he hurried Alec upstairs to his bedroom to talk the matter over. It is true that Roger felt a certain reluctance to be compelled thus to acknowledge that he had been busily unearthing nothing but a mare's nest; but, on the other hand, Alec must know sooner or later, and at that moment the one vital necessity from Roger's point of view was to talk. In fact, the pent-up floods of talk in Roger's bosom that were striving for exit had been causing him something very nearly approaching physical pain during the last few minutes.