Displayed with permission The American Surveyor July/August Copyright 2007 Cheves Media

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2 More than 12,000 feet up, the summit team gathers on the Continental Divide. L-R: Dog Ella, Warren Ward, Chris Trevillion, Justin Abrahamson, JB Guyton, Doyle Abrahamson, and Heather Robinson. According to Ward, Ella, a 12-year-old Australian Shepherd, has made about 20 trips to the top of the divide specifically for surveying in her career.

3 nce in a lifetime an opportunity may present itself to retrace the footsteps of the original surveyors of a line so significant that it shaped the course of our country s growth. >> John B. Guyton, LS

4 The 40th parallel, surveyed in the mid-1800s as the line that defines the border between the Nebraska and Kansas territories, was an important reference line for early surveyors. It was the basis of the United States Public Land Survey system used throughout much of the middle and western states, defining those neatly laid out squares that are clearly visible to modern day air travelers. The first mapping of this line across the plains became much more difficult when survey teams came upon a formidable obstacle, the Continental Divide in the Rocky Mountains. Baseline Road in Boulder, Colorado is aligned with the 40th parallel, where the high plains and the foothills of the Rocky Mountains meet. The 40th parallel intersects the Divide approximately 20 linear miles (as the crow flies) west of Boulder on a razor-edge ridge of loose rocks between Mt. Jasper and Mt. Neva. Back in the 1850s, United States Deputy Surveyors placed landmarks for the 40th parallel, beginning at the Zack Gowan gets a GNSS position on the 1867 stone west of the summit. Just above him, JB Guyton points to the stump of one of the bearing trees that proved the location. Second Guide Meridian (west of the 6th Principal Meridian) running westerly and ending at the Summit of the Rockies, as stipulated by their contract. This East-West Base Line would be used to establish the sections, townships and ranges across much of the midsection of the United States and more than 70 percent of the State of Colorado. Land descriptions today for much of the West are tied to this early survey. In 1859, U.S. Deputy Surveyors Jarrett Todd and James Withrow reached what is now Colorado and continued into the rugged, remote wilderness of the high Rockies until they reached the point where they thought the 40th parallel crossed the summit of the Rocky Mountains. They inscribed a cross on a rock face at the top of the steep ridge, as described in their field notes, declaring it the Summit of the Rockies, chiseling Utah on the west face. Eight years later it was discovered that this cross at the Summit of the Rockies was one ridge line east of the actual Continental Divide. The intersection of the Base Line with the Continental Divide was monumented in 1867 by United States Deputy Surveyor George Hill, who diplomatically declared it the Proper Summit of the Rocky Mountains. The act of pushing a straight line through rough terrain is a difficult task. The original surveyors who were charged with monumenting this line must have perceived the task as nearly impossible once they reached what is now known as Colorado s Front Range, yet they persevered. Somehow the early teams traversed up or around mountain peaks, valleys and sheer cliffs to set each section and quarter corner. They would have had to take readings on Polaris on every clear night in order to stay on the Base Line, camping out for weeks

5 Quad map indicates respective locations of various reference points. Proper Summit reference marker at a time and carrying their food or hunting for it (ll this while doing precise mathematical calculations and staying on line). And now, 150 years later, teams of modern surveyors retraced a few of their footsteps to search for these historic monuments. Throughout 2006, trudging through spring snow pack, summer thunderstorms and early fall blizzards, two teams of surveyors began by making multiple climbs to retrace and remonument the original Base Line dividing the Kansas and Nebraska territories in what is now Colorado. The notes taken in the field by the original surveyors in 1859 and 1867, obtained from the Bureau of Land Management in Denver, were used to locate the original points. The first team of surveyors included Doyle and Justin Abrahamson and Geoff Stephenson, who made several preliminary climbs in the spring to locate monuments along the 40th parallel on both the east and west sides of the divide. These locations were necessary to lay the groundwork for the discovery of the Summit of the Rockies cross set in In July of 2006, Jerry Penry led a team of surveyors from Nebraska, Kansas and Colorado, along with a geologist from the U.S. Geological Survey, to successfully find the lichen-covered cross inscribed in a stone face, marking the most westerly monument set on September 10, 1859 by Todd and Withrow (See Jerry Penry s article Rocky Mountain High, in the December 2006 issue). In late July I was part of another team made up of current and past presidents of the Professional Land Surveyors of Colorado, a member of the State Board of Licensure, and several county surveyors that made the arduous climb to search for the point on the Divide set by Hill in Using modern handheld Global Navigation Satellite Systems (GNSS) devices, the team was able to approximate the location of Hill s monument on a treacherous ridgeline. Climbing above the tree line to more than eleven thousand feet in elevation, the team was in search of controlling evidence of the Hill monument, which was described as a granite stone, 22 by 10 by 5, in a mound of stones. If, as expected, they had recovered this monument marking the southeast corner of Section 32, Township 1 North, Range 74 West of the 6th Principal Meridian, they would have drafted a monument record to memorialize and complete the parallel of latitude at the Proper Summit of the Rockies. But it was not to be.

6 The early surveyors used natural features where available as reference points and built cairns (rocks piled up as a landmark) to mark points that were then described in their field notes and survey reports. It is a generally accepted legal principle that an undisturbed, original monument takes precedence over other location techniques, including GNSS calculations, which is why the locations of Hill s cairns were so important. But the cairn on the Continental Divide was nowhere to be found. Perhaps it had been thrown by hikers over the steep easterly face of the divide into an unnamed lake below. So, the group was determined to use the original field notes and the traditional methods of measurement and topographic calls to locate other monuments to the west that were described and to remonument Hill s original Proper Summit of the Rockies. In early August, my daughter Heather Robinson and I were part of a team of surveyors that included Doyle Abrahamson, Zack Gowan, Warren Ward, Sam Knight and Chris Trevillian. We began our quest for the nearest monument on the Base Line immediately west of the lost Hill position. If it was still extant, it would be found on an impossibly steep mountain slope of stony, dry earth over 800 vertical feet directly below the divide, where each step requires extra effort to keep from sliding and falling. After repeated readings of the original notes and descriptions from the 1867 survey, with special attention to calls and references in the notes to topographic features and bearing trees, our search group was eventually able to solve the puzzle and successfully locate the original quartersection corner monument. We began by trying to find a vertically set stone etched as described in the field notes. Finding this vertically set stone, indistinguishable from the countless other rocks on the slope, required careful attention to the historic rules and procedures of the land surveyor. Beginning well before sunrise, we hiked up a narrow game trail following a stream bed through upland forest. After several hours of hiking, our hand-held GNSS units indicated that we had arrived in the general vicinity of the quarter section corner. Fanning out, we began a thorough inspection of the side of the mountain, moving steadily uphill on the steep talus slopes while scanning for likely-looking vertical stones. View from the summit ridge looking east toward the ridge where the original 1859 cross was set. JB and Doyle set one of the reference markers for the Proper Summit of the Rocky Mountains.

7 Most of the day passed with no sign of the corner. Doyle calculated both a line and two possible positions for the corner, one based on measured distances from the 1867 notes, and one based on topographic calls. Somewhere between these two possible positions is where we believed would be the best area to search for the stone. Heading back down to the creek in the middle of the valley, Doyle flagged an inter-visible line at several points along the Base Line. Returning up the slope, he identified one possible location, and we began to search every stone and tree and stump in the vicinity. We attempted to visualize where the two bearing trees called out in the original notes could have been. As the day grew short, and facing a five-mile hike back to the trucks, the other team members began to set reference markers that might be of use later, in case we came up empty on this climb. As GNSS data was collected, Doyle headed toward another alternate position. That s when we heard the words, Gentlemen, I think you may be in the wrong place Doyle, who had been with the group of surveyors that earlier discovered the inscribed cross from the 1859 survey to the east, had now discovered a pile of stones that had possibly been erected by humans. On the top of the center stone was an etching like a cross, or possibly even a 4 cut into the surface. Upon examination, the stone appeared that it might have been set upright by the use of four small supporting stones. The team was excited by the possibility that the original stone had been found. However, to prove it we needed to find additional evidence, such as the bearing trees called out in the original 1867 notes. The notes called for a 25 diameter spruce tree and a 30 diameter spruce tree. There were no such trees anywhere. None of the trees was bigger than a few inches in diameter. Could there have been such massive trees 140 years ago at this elevation near the bottom of the barren moraine? There was no particular evidence of logging. Was the climate so different then that trees that large could have grown on such a steep slope? There was no way to know for sure. We got out the compass and cloth tape and took a bearing from that small pile of rocks, then traversed South 20 degrees West a distance of 33 links (22 ) where the described tree should have been. There was nothing but brush, patches of tundra plants and loose rubble. Then we reached down and moved some debris from the spot where the notes called for a bearing tree, and there was a large rotted stump! The excitement of our exhausted team was growing. Then we sighted North 35 degrees East and measured 94 links (62 ) per the original notes. Measuring through a small tree and ending at a sheer cliff 20 to 30 feet high, it also seemed like an unlikely location for a large tree. We moved the surface debris and found another huge, rotted stump exactly where the notes said it would be! There could now be no doubt that the team had found George Hill s 1867 stone, set in its original, undisturbed position. The irrefutable evidence, after more than a century of avalanches, possible fires and violent weather, was revealed... a handshake with the past. Our team then had to set new reference ties, get GNSS coordinates on the stone and the stumps, write up and sign the field notes, and take some pictures. For the first time we took a moment to appreciate the setting, standing on a steep slope perhaps 500 feet above the valley floor. The original surveyor, George Hill, actually traversed this impossible slope and set these corners 140 years ago. The miraculous discovery of this monument was the last piece required to accurately reestablish the historic Proper Summit of the Rockies. So in September of 2006, using the positions of the cross and the vertical stone, our team made the arduous climb to the Continental Divide once more to reestablish the point described in the original notes as the Proper Summit of the Rocky Mountains. Several 3½ brass cap reference monuments were set in rocks near the summit point as accessories to the corner, permanently cemented in place with concrete. Then the actual summit point was similarly set and stamped, The Professional Land Surveyors of the State of Colorado, Inc., and thus memorialized for at least the next 140 years. The teams believe that surveyors of the past would have been pleased that their traditions and calculations were honored in the modern-day recovery of these positions. These positions that were so important to the establishment of the western territories remain critical points of reference for modern mapping. Somewhere, George Hill must be smiling. The summit crew on the Continental Divide points eastward to the ridge where the original 1859 cross was set. John Guyton is the principal surveyor and majority owner of Flatirons, Inc. in Boulder, Colorado, and has been in the surveying profession since He is the current President of the Professional Land Surveyors of Colorado, and is a Colorado Representative in the Western Federation of Professional Surveyors. He is licensed in Colorado, Wyoming, Arizona, California and Nevada.