National Geographic : 1977 Aug
On the Trail of Wisconsin's Ice Age By ANNE LABASTILLE, Ph.D. Photographs by CARY WOLINSKY STOCK, BOSTON I WAS DANGLING from a nylon rope, halfway down a sheer 100-foot palisade. Below me the St. Croix River, which flows in the Interstate Park between Wisconsin and Minnesota, glinted greenly in the summer sun. Above me Pitzi, my German shepherd, poked his head anxiously over the cliff edge and woofed uncertainly. I looked up to reassure him and, seeing the mighty rock face rearing against the sky, was suddenly staggered by the strength of the glacier's rushing meltwater that had carved this gorge. I was face-to-face with the handiwork of the awesome Wis consin Ice Sheet that had covered this region 10,000 to 20,000 years ago. Few places on earth have a greater variety of geo logic phenomena left by glaciation. Pitzi and I were traveling through Wisconsin on the trail of the Ice Age. A human head appeared beside Pitzi's. "You'd be just like bait on the line for some Ice Age fish!" shouted Dr. Adam Cahow, a professor of geography at the University of Wiscon sin at Eau Claire. I shuddered, rappelled rapidly to the cliff bottom, and unhooked myself. Adam scrambled down the side of the palisade and soon paddled up with Pitzi in the bow of our canoe. The tall, black-haired Scotsman has the uncanny knack of seeing the land as it probably looked at various stages of the glacier's advance. "Where you were hanging," he explained, "was underwater at one time. Meltwater from the glacier filled this entire valley." (Continued on page 188) Shimmering relic of the glacial age, a tiny lake beckons the author's party during an autumn foray into Wisconsin's ice-sculptured countryside. The continental ice sheet that blanketed most of the state left an eye-catching legacy of lakes and landforms, now to be linked by a cross-state trail.