advice, the boys told Mrs. Hardy their plans and drove to police headquarters. Chief Collig was just coming down the front steps as they pulled up.
âHave you solved the Mead mystery?â he asked, walking over to their car.
âWish we had,â Frank responded. âThat is why weâre here. Weâd like to go there again.â
The chief frowned. âI canât spare any of my men right now, Frank, and Iâd rather you wouldnât do it alone.â
âWeâll be all right, Frank assured him. âYou know we donât take any unnecessary chances.â
âWell, tell you what. Go ahead, but call me when youâre finished. If I donât hear from you within a couple of hours, Iâll send a squad car.â
âFine. And thanks a lot, Chief.â
Frank started the car, and soon the boys pulled into the Mead driveway. Frank concealed the car far behind the house.
âJust in case,â he said.
âSuppose we take different doors to work on,â Joe suggested. âIf you find a way in, yell!â
Frank gave the okay sign, and Joe hurried to the ornate door which faced the water. He surveyed the uniquely carved design critically. There was a keyhole hidden somewhere in the carving. But where?
Closely inspecting the door, Joe started at the right of the panel, pushing at each ridge of the symmetrical design. His search yielded nothing. He tried the left side, without success.
For half an hour he pushed and pulled, growing more puzzled each minute. Finally he tried combinations pressing with both hands on sections of the raised design. Suddenly his efforts were rewarded. Two pieces of molding moved. A keyhole!
âFrank!â he called elatedly. âIâve found one!â
The tall, dark-haired boy came running. âGreat!â he said. âHere, try the key!â
Joe did. A look of disappointment spread over his face. It did not fit.
âWell,â he decided, âI suppose it belongs to another door. Come on!â
They walked to the massive front door which Frank had worked on, and once more went over the intricate design. The upper and lower halves were outlined with a wide border, each containing an inset. At first glance the top inset seemed to depict a huge turtle.
Frank, standing at a little distance, suddenly had an idea. âSay, Joe, that turtleâs legs look almost like the strange Y symbol!â
Joe stepped back a few yards. âYouâre right! The two front feet and the right hind one do form a Y, sort of. Wonder if thereâs an answer here.â
Frank pressed his palm against the arched back of the turtle. Suddenly the reptileâs right hind foot moved to the side, revealing a large keyhole.
âLook!â he said excitedly, taking the key from Joe and inserting it. âSuccess!â
Holding his breath, Frank turned the key. There was a clicking sound and the door swung inward on hidden, noiseless hinges.
âHere goes!â Frank whispered as he pocketed the key and stepped over the threshold.
CHAPTER VII
The Mysterious Mansion
Â
Â
Â
Â
WITH a similar thrill of discovery, Joe followed Frank into the dark Mead mansion.
When their eyes became accustomed to the dimness of the shuttered house, the boys gazed around. They were in a large, carpeted entrance hall. The walls were solidly paneled in carved wood, and the Hardysâ flashlights revealed that the inside of the front door had the identical turtle design as the outside.
Slowly they went from room to room, peering through the open doorways. Library, living room, dining roomâall were tastefully decorated. But the house smelled musty and the furniture was draped with dust sheets, producing a gloomy effect.
âThis place hasnât been lived in for a long time,â Joe said. âIf Meadâor whoever that man on the road wasâstayed here, it must have been in the garage!â
âWho was that