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Zeutschel OS7000, 400 dpi, 8 bit, 8,924,380 bytesThis survey was made wit the plane table and stadia rod, controlled by points located by triangulation from a measured base and bench marks established with a Y-level. The scale adopted was 50 feet to an inch, and the contour interval 2 feet, except where slopes were too precipitous for this interval, when only the 10-foot contours were drawn. (see map 1). After the completion of this survey the reservoir site, to an elevation 200 feet above the bed of the river in the river gorge, was mapped on a scale of 5 inches to a mile in 10-foot contours. For the control of this map a base was measured 3,112 feet long and expanded to neighboring high points, so as to cover most of the reservoir site with a network of triangles. This triangulation was performed with a Heller & Brightly transit, reading to single minutes; sights being taken to signals composed usually of cairns of stone. A line of careful Y-levels was run from the dam site up the river for a distance of about 15 miles, locating the point of crossing of each contour. The contour 160 feet above the bed of the river at The Buttes was traversed and leveled. The other contours were located by sights upon stadia rod and intermediate sketching. The areas and capacities of the The Buttes reservoir site for each 10 feet of elevation above the surface of the ground at the dam site are given in the following table: Area and capacity of Buttes Reservoir Site. Contour flow line. Area. Capacity, section. Capacity, total. Acres. Acre-ft. Acre-ft. 10 20 100 100 20 71 450 550 30 229 1,500 2,050 40 397 3,130 5,180 50 533 4,650 9,830 60 741 6,370 16,200 70 928 8,345 24,545 80 1,105 10,165 34,710 90 1,329 12,170 46,880 100 1,566 14,475 61,355 110 1,769 16,675 78,030 120 2,029 18,990 97,020 130 2,367 21,980 119,000 140 2,746 25,565 144,565 150 3,149 29,475 174,040 160 3,602 33,755 207,795 170 4,118 38,600 246,395 180 4,609 43,635 290,030 190 5,133 48,710 338,740 200 5,651 53,920 392,660--- 392,660 The investment thus far described occupied the party until the 24th of February. SOUNDING FOR BED ROCK. Sundry attempts had previously been made by other parties to locate the depth of bed rock at various parts of the gorge, all of them without success. The method used was the driving of iron or steel rods into the bed of the river. Numerous reports were obtained of soundings varying 40 to 50 feet in depth without striking bed rock. This fact at once placed a serious phase upon the proposition of a dam at this point, and it was desired to obtain a log of the material constituating the bed of the river from surface to bed rock in order to form as idea of the difficulties to be encountered in excavating for a dam foundation. For this purpose the following advertisement was inserted in the Arizona Star in the month of February. PROPOSALS FOR DRILLING. UNITED STATES INDIAN SERVICe Florence, Ariz., January 15, 1896. Sealed proposals, indorsed ""Proposals for drilling,"" and addressed to the under signed at Florence, Pinal County, Ariz., will be received until 12 o'clock noo