The operative passed up a pair. "Ah," chuckled the detective, unscrewing the binding-posts and lifting off a hard rubber cap. "Ah, see here!" Delaney rose and peered over the captain's shoulder straps. The two men watched Drew's nimble fingers trace out the mechanism of the electric pistol. "It's simple!" declared the detective. "It's very simple and ingenious in construction. It's a crowning wonder to me that some one hasn't used this sort of device to carry out a wholesale slaughtering. Suppose they never thought of it." Drew glanced at the silent mound under the Persian rug. "The wrong road," he whispered tersely. "He took the wrong road. He was a mechanical and electrical genius. He was a patent expert." Delaney worked his brows up and down. "Shall I call Miss Stockbridge?" he asked. "I'll do it," Nichols said, turning and hurrying through the portières. He returned with Loris leaning upon his arm. Her eyes were glazed and tear-laden. She held a tiny, limp lace handkerchief between her trembling fingers. "There's no danger," said Drew. "Come here, Miss Stockbridge," he added. "I want to show you what was all ready for you." The detective raised the hard-rubber receiver. "Here we have the diaphragm," he said, pointing. "It's a round plate of soft iron. It's secured to the rubber by an insulated ring. It is the part you press up to your ear when you listen at a telephone. There's a small hole punched in this one. The same sized hole extends down through the center core, or magnet. This hole isn't rifled. It couldn't well be rifled save with special machinery. That's why the bullet found in Mr. Stockbridge's brain was without longitudinal scorings. It was fired from a smooth-bored pistol." "That's what you thought!" blurted Delaney with loyalty. "I was at sea," said Drew. "Now," he continued, "we have a live cartridge at the opposite end of this core from the diaphragm. See it?" Loris leaned over the little table. "Right here!" The detective pointed. "That is a twenty-two cartridge with a cupronickel bullet. See the cap? See how it is held from coming back by those tiny screws about the rim?" Loris nodded and gathered up her straying hair. "Now," continued Drew. "Now, this cartridge was exploded by the action of the human voice. Here's a tiny spiral of very slender platinum wire. It must be number forty, at least. That's very fine! This spiral is in series with the winding about the magnets. The same current pulsated by the human voice which actuates the receiver diaphragm, also passed through this spiral. Now," Drew paused. "Now," he added with rising voice, "here is a tiny charred piece of match-head, I guess. It was set in the coil. It flared when the wire became hot. The heat was sufficient to ignite the cap. See it!" "I see it!" exclaimed Nichols.