Natural Bridge Saturday, April 4, 1925. Started at 7:45 A.M. north along the western side of Rose Creek Lake. It is a beautiful drive in and out the spurs of the Sierra conglomerate. The Paleogene series goes along the road about 2-3 miles and then comes Archingite granite. Then it is all the gray Sierra Conglomerate. North of the lake we are on the west side of the Tonto River in Tonto (Spanish for forts) Basin. Today the river has cut deeply through the Sierras and finally we go some miles through plaza deposits with much dirty gypsum. Some gypsum occurs in veins, Have pieces of both kinds. As we go on three we see elevated terraces. To the west are the high Magatzal Range of Archingite, and to the east are the low hills Sierra Ancha having Cambrian in the upper parts. North of Paeball the terraces are especially once scarred. The highest one is many hundred feet above the Tonto river and is now almost dissected. The next lower terrace dips 200-300 feet and in places is made up of 4 smaller benches. This terrace is now the cliff of two Tonto River bottom and maybe 75 to 100 feet high. These terraces go from Paeball to road to Bisola east Finally we come upon high land of lava in which the Tonto lies in a gulch. Our main road climbs Tonto Hill. Here I took 2 pictures looking S.W to Magatzal