Page:The Master of Mysteries (1912).djvu/79

 she was, so to speak, still in her student days, to work out her own clues. Later, in case she had erred, he indulgently pointed out her mistakes. It was in some such tacit understanding that they now left the Macdougal Street tenement and made their way back to Astro's cozy studio.

Once there, she could see from the way in which he donned his turban and robe, lighted his water-pipe, and disposed himself on the cushioned divan in his favorite corner, that he had already solved the problem to his own satisfaction. Above the top shelf a row of the ancient Toltec, laughing heads grinned down on him; farther on, brazen implements and slabs of marvelous jade wrought with hieroglyphics gleamed dully, adding their touch of mystery to the man beneath. On the table were the sheets of paper and the dividers and rule with which he had been plotting an intricate curve, and this work he again took up immediately. Valeska withdrew. After an hour's work, heedless of the passage of dinner-time, he smiled, carefully laid aside his instruments, and turned to a plaster cast hung against the wall.

"It is true, then, as I thought, about you, Monsieur Voltaire," he murmured, half aloud. "The line of the upper half of the perimeter of that right ear of yours is a logarithmic spiral, of which the equation is $$x^2 = 2ab + y$$." He threw back his head and yawned.

Valeska glided in. "McGraw has come with Antonio," she whispered, "and has been waiting half an hour; but I wouldn't interrupt you until you had finished your calculations. Shall I let them in now?"

Astro yawned again, luxuriously. "You are too indulgent of me, my dear girl, I'm very much afraid.