Meantime, Lawrence North and the detective were discussing architecture. They were in the library and the plans of the house were spread out before them. “I’m interested,” North said, looking eagerly at the plans, “for I’m always fond of plans. And, too, I want to prove my contention that there’s no space unaccounted for. At first, I thought there might be a bit of spare room between this wall and this,—you see. But that jamb is merely the back of a small cupboard in the hall. Can you find any hint of false building?” “No; I can’t,” Wise admitted, and then he unfolded his theory of a double door frame,—or, rather a hinged door frame or window frame. “That,” said North, “must be looked for in the house, not on the plans. But I doubt it. Any such thing would be apt to show the joints after years of disuse. You see, this house hasn’t been lived in before for a long time.” “Then I’ll have to give up the notion of a double door,” and Wise sighed. “Now, here’s another matter. I want to go out in a boat,—a good motor boat, and have a look round the sea and the cliff and observe for myself the possibilities of an expert climber entering the grounds from that side. Will you take me in your boat? I’m told you have a fine one?” “Of course I will,” was the ready response. “When do you want to go?” “As soon as you can make it convenient. I want to work rapidly, as things are coming to a focus, and I don’t dare delay.” North stared at him, as if wondering how a trip in his boat would advance the work definitely, but the detective had no intention of telling him about the kidnapper’s letter and, too, Wise wanted to view the whole headland from the ocean. The result was that the two started off at once, and going first to North’s bungalow to get his keys, and also his man who helped run the boat, inside of an hour Pennington Wise found himself out on the ocean with North, and Joe Mills, who, though taciturn and even grumpy, was a good navigator. “Remarkable cliff!” Wise exclaimed, amazed at its effect from below. “It’s all of that!” North said; “most wonderful cliff on the whole Maine coast, they say. Notice the overhang, and then tell me if any one could climb it!” “No human being could!” Wise declared. “And I can think of no animal,—unless a spider. Go clear round to the other side, will you?” North gave orders and Mills drove them round the great headland, and on all sides it was as massive and forbidding as the first view. “High tide, isn’t it?” asked Wise, as they went on beyond the headland, and then turned back again. “Yes,” said North, glancing at the rocky base. “Almost top notch.” “Rise high?” “Very. Twenty feet at least.” “I thought so. Marvelous tides up in this locality. Well, there’s nothing more to be discovered by gazing at these rocks and water: let’s go home.” On the trip homeward, the detective proved himself so entertaining that North went back to Headland House with him.