In one corner of the great room was a small trapdoor. Nick lifted it and found that a straight ladder led to another warehouse, not so lofty as the one above. Evidently it had been used to store ice, too. The detective could not understand why there should be this separate storeroom until he had examined a long tank at one end, and found that it was an ammonia generator, with an engine underneath. “They used to make artificial ice here, I see,” muttered Nick Carter. He walked very softly across the floor, because he was convinced that in the room below there were persons who would come after him quickly if they were aware of his presence. In a corner of this second room was a sort of vestibule, with two doors. It was easy to open these doors, for neither was locked. The detective found himself at the top of a long flight of stairs which turned sharply not far from the bottom. From where he stood he could look down into what appeared to be an office, furnished with a roll-top desk and a chair. There was other furniture, no doubt. But the desk and chair were all Nick could see, except the old linoleum with which the floor was covered. Low voices came to him--so low that if his ears had not been sharper than those of most people, he would not have been able to make out what was being said. As it was, he not only caught the words, but also he recognized the voices as those of Don Solado and Prince Miguel. Solado was speaking when Nick Carter first heard any of the conversation, and what he said was of personal interest to the detective. “Now we know who that man is who pretended to be Marcos,” were Solado’s words, bitten off with a spitefulness that told how viciously in earnest he was, “the thing to do is to get him out of the way.” “Permanently?” asked Miguel, in a languid tone. “Permanently,” came the quick assent. “We can’t afford to have an interfering individual like him disturbing us when we are planning for the welfare of our beloved country, Joyalita.” “Solado!” interrupted Miguel. “Well?” “You would oblige me if you were not quite so much of a humbug.” “Your highness?” spluttered Solado, his tone indicating that he was much scandalized. “You know what I mean, Solado,” was the imperturbable response. “Don’t be so confoundedly diplomatic. Call a spade a spade, and don’t try to fool either yourself or me.” “I don’t understand----” “Oh, yes, you do. This talk about working for the welfare of our beloved country is all very well when you are speaking for the benefit of strangers, and I have no objection to your giving it to Marcos, himself. But it only wastes precious time when you and I are alone together.”