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westward from Toroweap Valley. In this section several features illustrating the early stages of canyon cutting and of local vulcanism will be concealed. Also covered will be remnants of lavas that flowed down the river channel and sediments, in two places, formed in ancient lakes or reservoirs behind natural lava dams. A detailed account of these remnants of lava flows and other features of local vulcanism appears in a paper by McKee and Schank titled "The Lower Canyon Lavas and Related Features of Toroweap in Grand Canyon," published in the Journal of Geomorphology, Volume 5, Number 4, pages 243-273 (1942). d. Recreation The most obvious change in recreational use of the canyon brought about by the Bridge Canyon Project would be the limitation of the traditional and exhilarating experience of wild river boating, for which the Grand Canyon is famous. This unique form of recreation was beginning to show a marked increase prior to the closure of the Glen Canyon Dam. Since 1955, more than 1300 persons enjoyed boat trips through Grand Canyon; nearly 400 of these made the trip last year. Undoubtedly, the running of the Grand Canyon would grow in popularity in the years ahead as the quality of such an experience and its safety with proper preparation, equipment, and guidance became more widely known. The proposed low Bridge Canyon Dam would reduce the amount of possible river running through the Grand Canyon by more than 80 miles, a reduction of 36.8 percent. 2. Values to be Gained A fair evaluation of the effects of the proposed Bridge Canyon Reservoir cannot be made without giving consideration to artificially created values which will result. With the completion of the dam and a highway from U. S. 66 to the damsite, the Bridge Canyon Reservoir would become a new recreation attraction of the region. This wild and presently relatively inaccessible area would be opened to large numbers of people who will want to take boat trips on a fjord-like reservoir set in the incomparable scenery of the Grand Canyon. 3Epson Perfection 4870 Photo, 400 dpi, 8 bit, 15,978,496 byte