Pub. 15 2022 Issue 1 • UCLS Foresights 29 Editor’s Pen It would be difficult. USGS Topographic Engineer Claude Birdseye faced enormous challenges to run an unbroken traverse and level line for 251 miles through the Marble and Grand Canyons. His expedition team included able boatmen, a geologist, hydrologist, second topographer, rodman and cook; ten men in all. Four 18-1/2’ by 4-1/2’ wooden boats “decked fore and aft and fitted with water-tight hatches and airtight compartments” conveyed the party and instruments consisting of “specially-constructed plane-table and telescopic alidades, a custom fourteen-foot long, folding stadia rod (which could be read from 2800 feet away, allowing for long shots through the canyons),” and “three additional alidades of varying styles (sight, Bumstead, and Gale), extra stadia rods, an aneroid barometer, tripod[s], four Brunton compasses, levels, tapes, field glasses, and field books.” With everything assembled, the team set off from Lees Ferry on August 1, 1923. Seven miles downstream they encountered their first rapid (Badger Creek), the first of 84 rapids on their journey. Birdseye would report there were only three instances where portaging was necessary, sometimes by using “long ropes held by men stationed along a cliff” or by taking them out and “dragging them over the rocks.” Each boat weighed 900 pounds. Their fifth boat was of light canvas and was primarily for the rodman’s use. To their regret, it was lost at the thirteenth set The Lost Canoe of rapids and swept away. The survey continued, mapping to elevation 3150’ (scale 1:31,680), and with contour intervals of 50’ on land, 5’ on water surface. At potential dam sites they adopted a scale of 400 feet to the inch, contour intervals of 10’ and made a cross-section along the axis of the proposed dam. They developed a rhythm to their work. On the evening of September 18, Birdseye reported, “the river had begun to rise ... and continued to rise at the rate of about 18 inches per hour and reached the peak of 21 feet the following afternoon.” They waited four days for the river to subside. While the men calmly waited, the light canvas boat lost at rapid #13 was recovered a hundred miles downstream. Newspapers all over the country breathlessly reported, “The explorers tonight are believed to be battling their way through raging currents in the rock-strewn, tortuous river in one of the most dangerous gorges of their voyage,” and likening the journey to “shooting Niagara Falls in a barrel.” On October 13, 1923 the Birdseye expedition closed to a benchmark erected as the highest upriver point in a 1920 survey. The elevations closed within 4-1/2 feet, a remarkable achievement. v See the accompanying article – The Grand Canyon Expedition 1923. This story originally ran in Backsights, Published by the Surveyors Historical Society Spring 2021, Volume 40 Number 1. By Mary M. Root
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