“I was working—in my study—from six o’clock until half past nine.” He paused, but evidently felt that further explanation was desirable. “For several months I’ve been working on a modification of the ether-string theory to account for the interference of light, which the quantum theory is unable to explain. Dillard told me I couldn’t do it”;—a fanatical light came into his eyes—“but I awoke early yesterday morning with certain factors of the problem clarified; and I got up and went to my study. . . .”
“So that’s where you were.” Vance spoke carelessly. “It’s of no great importance. Sorry we discommoded you to-day.” He beckoned with his head to Markham, and moved toward the screen door. As we stepped upon the range he turned back and, smiling, said almost dulcetly: “Mrs. Menzel is under our protection. It would pain us deeply if anything should happen to her.”
Drukker looked after us with a sort of hypnotized fascination.
The moment we were out of hearing Vance moved to Heath’s side.
“Sergeant,” he said in a troubled voice, “that forthright German Hausfrau may have put her head unwittingly in a noose. And—my word!—I’m afraid. You’d better have a good man watch the Drukker house to-night—from the rear, under those willow trees. And tell him to break in at the first scream or call. . . . I’ll sleep better if I know there’s a plain-clothes angel guarding Frau Menzel’s slumbers.”
“I get you, sir.” Heath’s face was grim. “There won’t be no chess players worrying her to-night.”
CHAPTER XIV.
A Game of Chess
(Tuesday, April 12; 11.30 a. m.)
As we walked slowly toward the Dillard house it was decided that immediate inquiries should be made regarding the whereabouts the night before of every person connected in any way with this gruesome drama.
“We must be careful, however, to drop no hint of what befell Mrs. Drukker,” warned Vance. “Our midnight bishop-bearer did not intend that we should learn of his call. He believed that the poor lady would be too frightened to tell us.”