A Delicate Balance

A Delicate Balance. . Geologists speculate that the Old Man of the Mountain, formed by a retreating glacier during the last ice age, looked out over Profile Lake for more than 12,000 years. On May 3, 2003, the delicate balance that had held the “Great Stone Face” in position through the ages came to an abrupt end., (Captions) , The Old Man was made of five slabs of Conway granite balanced one atop another. As shown in this drawing of the south side of the stone face, but hidden in the familiar view from the north, was a cavern about four feet wide behind the Old Man’s chin (Block 5). which ran almost the entire width of the Old man’s face. About 80% of the chin block hung out over the cliff. Thus, just about two feet of the chin was anchored to the cliff, held there only by the weight of the four slabs above it. Amazingly, the other four slabs were positioned so that the center of gravity of the chin block was within that two foot span. This allowed the Old Man to balance on its chin for centuries., 1 – The Old Man’s visage was delicately balanced on the chin, with weight of upper blocks holding the chin in place., 2 – Water damage eventually moved the chin’s center of gravity, causing the chin block to move slightly forward past the cliff face. When this happened, the chin toppled down the cliff., 3 and 4 – With the chin gone, the support from below for the upper lip and nose was removed. The weight of those slabs, combined with chemical water damage they sustained through the years, caused them to break and topple soon after the chin., 5 – The forehead slab, left unsupported, quickly followed and the Old Man of the Mountain, as we had known it, was gone., A photograph taken shortly after the Old Man’s disappearance provides further evidence that water damage to the granite through the years caused the rocks to break and tumble rather than to slide. What appears to be dirt actually is granite that was “rooted” by water. (The local granite is loaded with the mineral potash feldspar, which is particularly reactive with water.) . This historical marker is in Franconia in Grafton County New Hampshire