Mr. Grimm’s teeth closed with a little snap.

“Did you happen to notice any time this evening a stout gentleman, with red face, near the conservatory door?” he asked.

The servant pondered a moment, then shook his head.

“No, sir.”

“Thank you.”

Mr. Grimm was just turning away, when there came the sharp, vibrant cra-a-sh! of a revolver, somewhere off to his left.  The president!  That was his first thought.  One glance across the room to where the chief executive stood, in conversation with two other gentlemen, reassured him.  The choleric blue eyes of the president had opened a little at the sound, then he calmly resumed the conversation.  Mr. Grimm impulsively started toward the little group, but already a cordon was being drawn there—­a cordon of quiet-faced, keen-eyed men, unobstrusively forcing their way through the crowd.  There was Johnson, and Hastings, and Blair, and half a dozen others.

The room had been struck dumb.  The dancers stopped, with tense, inquiring looks, and the plaintive whine of the orchestra, far away, faltered, then ceased.  There was one brief instant of utter silence in which white-faced women clung to the arms of their escorts, and the brilliant galaxy of colors halted.  Then, after a moment, there came clearly through the stillness, the excited, guttural command of the German ambassador.

“Keep on blaying, you tam fools!  Keep on blaying!”

The orchestra started again tremulously.  Mr. Grimm nodded a silent approval of the ambassador’s command, then turned away toward his left, in the direction of the shot.  After the first dismay, there was a general movement of the crowd in that direction, a movement which was checked by Mr. Campbell’s appearance upon a chair, with a smile on his bland face.

“No harm done,” he called.  “One of the officers present dropped his revolver, and it was accidently discharged.  No harm done.”

There was a moment’s excited chatter, deep-drawn breaths of relief, the orchestra swung again into the interrupted rhythm, and the dancers moved on.  Mr. Grimm went straight to his chief, who had stepped down from the chair.  Two other Secret Service men stood behind him, blocking the doorway that opened into a narrow hall.

“This way,” directed the chief tersely.

Mr. Grimm walked along beside him.  They skirted the end of the ball-room until they came to another door opening into the hall.  Chief Campbell pushed it open, and entered.  One of his men stood just inside.

“What was it, Gray?” asked the chief.

“Senor Alvarez, of the Mexican legation, was shot,” was the reply.

“Dead?”

“Only wounded.  He’s in that room,” and he indicated a door a little way down the hall.  “Fairchild, two servants, and a physician are with him.”

“Who shot him?”

“Don’t know.  We found him lying in the hall here.”