"_Who speaks_," said the quiet, insistent voice, "_does not matter. Nor the spot from whence I speak. The important thing is that you hear and obey my words. Make not the error of hurling the tribute money in anyone's face. Deliver it to your superior officer--but see that you get a signed receipt for it. Do you understand?_" "No!" said Corporal Tandred weakly. "I hear a voice speaking, but see no one. I don't understand--" "_It is not necessary that you understand. Just obey. Get a signed receipt for that money. That is all!_" "Wait!" cried Corporal Tandred. "Wait a minute--!" He was talking to himself. Even as he spoke, he sensed that. The strange, semi-electrical feeling of a nearby presence was gone. * * * * * For a moment he sat stock-still, trying to sooth his ruffled nerves. His effort was not altogether successful; he started the unicar with a jerk, and sped down the avenue at a rate of speed forbidden by civic ordinance. A uniformed attendant frowned disapproval as he screeled to a stop in front of the Revenue Office, but Corporal Tandred paid him no heed. He hurried straightway to the central office, there deposited his collections before his captain. The captain nodded abstractedly, then, his attention drawn by some oddness in the subaltern's appearance, raised a questioning eyebrow. "What is it, Tandred? Anything wrong?" "N-no, sir," said the corporal uncertainly. "Someone make a complaint? That it?" "Well, sir, there _were_ several complaints. Citizens find these new taxes hard to swallow, sir; very hard." The captain laughed derisively. "Sheep! Let them suffer. It is no concern of ours. The Overlord has a militia to maintain. Well ... that is all." He waved a hand in dismissal. Corporal Tandred said hesitantly, "Yes, sir. But the ... the receipt, sir?" "Receipt? For what?" "For the money, sir. Regulations, sir." "Oh, yes." The captain grinned caustically. "Don't you trust me, Corporal? You never asked for a receipt before that I can remember." "N-no, sir. I mean ... of course I trust you, sir. I just thought that ... that this being a new tax--" "Very well; very well!" The captain scribbled, tore a receipt from his pad, and handed it to the underling. "You may go now, Corporal." "Yes, sir. Thank you, sir." Corporal Tandred left hurriedly, still uncertain _why_ he had obeyed the instructions of the mysterious voice, still uncomprehending as to _why_ he should have asked for a receipt, but with a strong conviction he had done the wise thing. He was right! Five minutes later the money vanished mysteriously from the captain's desk. Or so, at any rate, in stern, judicial court the captain swore repeatedly to an even colder superior. In vain the captain protested his innocence and tried to shift the blame to Corporal Tandred's shoulders. The Corporal was in the clear, triumphantly acquitted through possession of a signed receipt for the missing money.