up the sculptured legs, and finding a foothold on the god’s ceremonial staff, I grasped the arm to draw myself still farther up. As I did so, I felt the immense mass of rock sway, my feet slipped, I clutched wildly at the arm, uttered one terrified yell and fell crashing to the earth below. Dazed, stunned but luckily unhurt, I sat up and stared incredulously at the colossal image above me. Standing out at right angles to the cliff, staring down at me from directly above my head, was the huge stone face of the god, while in place of the flowing robe and sandaled feet, a black opening yawned in the face of the precipice. I gasped. The gigantic carving was movable, my weight or my touch upon the arm had swung the upper portion forward and had disclosed a hidden opening, a secret door! What did it mean? What lay within that dark portal in the cliff? That it was something of the utmost importance, something inexpressibly sacred or precious was certain. To have carved that gigantic figure, to have designed the mechanism, to have balanced the many tons of carved stone so nicely that it could be swung at a touch must have been an herculean, a most difficult, task requiring the labor of years; a work that never would have been undertaken except for some vital, some most important purpose. And the fact that the massive pivoted door had been formed in the likeness of Kukulcan, pointed to the secrets within the opening being associated with that god. Perhaps--my pulse quickened at the thought and I felt a strange thrill--perhaps I was at the threshold of Mictolan, at the portal of the hidden city I sought!