The surveys made by the State engineer showing the irrigation development of Boise Valley will be available for use and of great value to the Reclamation Service in studying the irrigation conditions in connection with the Payette-Boise project. The determination of the rights on upper Snake River Valley is also a matter of great importance, involving as it does the rights of ditches irrigating at present between 250,000 and 300,000 acres of land, and capable of irrigating, by enlarging and extending, upward of 700,000 acres in this valley. But before all the lands of this section can be irrigated it will be necessary to begin the construction of reservoirs on several of the main branches of Snake River. The irrigation survey of this valley now being made by the State engineer will show the present condition of development and will serve as a basis for recording all irrigation development made subsequent to the adjudication of existing rights. For this reason the results of the work now being done under his direction will all be available for use by the Reclamation Service, and will serve as a basis for determining the relation which the various irrigation communities in this valley will bear to the Minidoka and Dubois projects, and for the determination. of the benefits which other portions of the upper valley will receive through the construction of storage works which the Government will doubtless be asked to undertake in the near future. Owing to the importance of this survey and to the fact that the results will be largely used by the Reclamation Service in the near future and to the further fact that the State had made no provision for bearing the expense of such survey, the State engineer requested the Reclamation Service to share the expense of the undertaking. This suggestion was favorably received, and the following contract was entered into with the State engineer: This agreement, made and entered into this 8th day of August, 1904, between F. H. Newell, chief engineer of the Reclamation Service, for and on behalf of the United States Geological Survey, party of the first part, and Wayne Darlington, State engineer of the State of Idaho, party of the second part, witnesseth: Whereas the Reclamation Service, a part of the United States Geological Survey, is authorized by the act of Congress approved June 17, 1902 (32 Stat. L., 388), to make surveys and investigations of the water supply of the State of Idaho, for the irrigation of arid lands therein, and is authorized to use the reclamation fund established by said act for such purposes; and Whereas the State engineer of the State of Idaho is engaged in a survey of the water supply of Snake River, Idaho, and the determination of said water supply is necessary for the investigations of the said Reclamation Service, in connection with irrigation works now under investigation under the provisions of the said act: Therefore, be it agreed, That the Reclamation Service will on the submission of proper pay rolls prepared in the manner required by its rules and regulations, and certified by D. W. Ross, district engineer of said service, in charge of its work in Idaho, pay one-half of compensation due the persons actually employed upon the field and office work of such survey. In consideration whereof the party of the second part agrees to conduct said surveys, so far as may be feasible, in accordance with the regulations of the United States Geological Survey, and to furnish promptly to said D. W. Ross, Lepresenting the party of the first part, the original or certified copies of all data obtained, and of all maps constructed, in pursuance of this agreement: Provided, That if originals are furnished, copies thereof shall be made by the party of the first part and promptly returned to the party of the second part. All copies of data or of maps so made or furnished to the party of the first part may be used and published by it in the usual manner, due credit to be given to the party of the second part. The party of the second part shall cause monthly reports of the progress of the work to be made to the party of the first part, in accordance with its regulations. The provisions of this agreement, when duly executed by and on behalf of both parties and approved by the Director of the United States Geological Survey, shall be considered as binding upon both parties from June 1, 1904, until the work now undertaken by the party of the second part shall have been completed, which is estimated as seven months from said date. In testimony whereof the said parties have hereunto set their hands the day and year first herein written. Executed in duplicate. Approved: F. H. NEWELL, Chief Engineer Reclamation Service, for and on behalf of the It is estimated that the field work in connection with this survey will be finished at least by January 1, 1905, and that the results will be available about a month later. In addition to bearing part of the expenses of the survey referred to, the Reclamation Service, during the irrigating season just ended, mnade measurements of all the canals diverting water from Snake River for use in the irrigation of these lands. These measurements were made by William G. Davies, engineering aid, in connection with his regular work of stream measurement. Daily observations were made of the discharge of all the principal canals, the record showing the continuous discharge during the greater portion of the season. The State engineer's survey will show the area irrigated by each canal, and will thus afford a basis for very close estimates of the duty of water in this portion of the valley. The data relating to this feature will be compiled after the close of the field season. OPERATIONS IN KANSAS. By CHARLES S. SLICHTER. INVESTIGATION OF THE UNDERFLOW OF THE ARKANSAS RIVER. An investigation of the underflow of Arkansas River was begun June 11, 1904. The work consisted in accurately mapping the water plane or ground-water level for a distance of 6 to 12 miles from the river channel and in observing by the electrical method the rate of movement of the underflow. The level party consisted of Ray Owen, levelman, Frederick Thwaites, a field assistant acting as rodman. The ground-water levels were obtained by observations of the water levels in private wells on the farms in the neighborhood of the river and by observations in a few wells which were sunk especially for the purpose. The slope of the water plane was found to be between 7 and 8 feet to a mile in a general easterly direction and from 2 to 3 feet to a mile toward the river channel from the country immediately to the north and immediately to the south of the river. The southern margin of the river valley is bordered for 5 to 10 miles to the south by sand hills, only partly covered with natural vegetation, which extend from east of Dodge, Kans., to the Colorado line on the west and beyond. North of the river valley the ground rises rather abruptly to the high plains, with their well-known level topography and compact sod of native grasses. The slope of the water plane toward the channel of the river from the north is, as has been stated, about 23 feet to a mile; however, after passing to the north for a distance of 10 to 14 miles the southward-sloping water plane changes to a northward-sloping water plane, the land at the same time gently dipping to the north toward the valley of White Woman. Creek. The easterly slope of 7 to 8 feet to the mile is maintained, however, quite constantly throughout all of this region. THE RATE OF MOVEMENT. Determinations showed a rate of movement of the ground waters much greater than had been expected. The first set of underflow stations were established in a north-south line about 2 miles long at a point about 23 miles west of Garden. The velocities of the ground water at the stations established on this line were found to be remarkably uniform, varying for the most part between 8 and 11 feet per twenty-four hours. The gravel, except occasional layers of silt, was also exceedingly uniform in size and character of grain, a large percentage of the material consisting of grains larger than the size of wheat. The direction of motion at these various stations was in general toward the east, but exceptions were noted from time to time. At the time field work was begun the channel of Arkansas River was dry, as it usually is from June to October. The last summer, however, was exceptional, high floods being of constant occurrence throughout the summer. One of these floods came down the river soon after the first underflow stations were established near the bank of the river, offering an excellent opportunity for determining the influence of the river waters upon the underflow. At one underflow station, situated near the north bank of the channel of the river 2 miles west of Garden, the direction of the flow of the ground waters was greatly changed by the flood in the river. It was therefore possible to measure the rate at which the river contributed to the ground waters at this point. It was found that the water during the early stages of the flood flowed away from the river at the rate of 8 feet per twenty-four hours. It was not only possible to actually determine this rate of flow by the use of the electric underflow meter, but the northward progress of the water from the river into the gravels could be noted by observation of the changes in the temperature of the ground waters as they flowed northward, the river water being very much warmer. It was also possible to partly trace the inwardmoving ground water originating in the river by the change in the chemical composition of the water. Apparatus was at hand for determining the alkalinity, hardness, chlorine, and the total solids dissolved in the water. A further verification of the inward-moving ground water was found in the changed slope of the water plane during the flood periods in the river. The water plane sloped away from the river about 8 feet to the mile during the first stages of high water, corresponding quite accurately with the observed velocities of the water. Similar determinations were made at a series of stations near Sherlock, 7 miles west of Garden, and at Deerfield, 15 miles west of Garden, and at points near Lakin and Hartland, 21 and 28 miles, respectively, west of Garden. The results differed little from those obtained at the first set of stations, except that more sorting of the gravels had taken place at the points just named, giving greater variety to the rate of movement. The usual velocities varied between 4 and 24 feet per twenty-four hours, the average velocity at 31 underflow stations being 7.9 feet per twenty-four hours. The direction of motion at these various stations corresponded for the most part to the main direction. of the river valley, but stations near the sand hills south of the river showed a noticeable northerly component. VARIATION IN CHEMICAL COMPOSITION OF THE WATER. Chemical tests of the underflow waters at the various stations showed a marked decrease in the quantity of dissolved solids in the water with the depth penetrated. In sinking test wells at almost any point in the bottom lands of Arkansas River the increasing softness of the water can be noted almost from foot to foot. At a considerable depth, say from 60 to 100 feet or more, there are found waters that are popularly called in this region "second" or "third" waters, which are very much softer than the water obtained from shallow wells; and at the points located in the sand hills south of the river there are places where shallow wells furnish water much softer than the so-called second or third waters found in the vicinity of Garden. The total solids in the ground water determined at wells in the first camp, 2 miles west of Garden, varied from 121 parts per 100,000 for water taken 4 feet below the water plane to 103 parts per 100,000 for water taken at 6 feet, and 80 parts per 100,000 for water taken at 14 feet. Water from the railroad well, 130 feet deep, at Garden showed total solids of 16 parts per 100,000. Water in the sand hills south of the river at a depth of 9 feet showed 33 parts per 100,000 total solids, and another well, deeper but of unknown depth, showed 6 parts per 100,000 total solids. The tendency of the ground water near the surface in the bottom lands of the river to run high in dissolved solids seems to indicate that this increased hardness is due to the concentration of the ground water by evaporation. The water plane in these bottom lands lies close to the surface of the ground and is subject to frequent fluctuations, due to changes of conditions in the river itself. These changes are sufficient to account for a large excess of dissolved solids, and it is believed that no other explanation is necessary. ORIGIN OF THE UNDERFLOW. The summer's investigation indicates that the water of the Arkansas underflow has its origin in the rainfall upon the sand hills to the south of the river, upon the bottom lands of the valley, and upon the plains north of the river. The average rainfall in the vicinity of Garden is about 20 inches per year. A very large part of this must pass into the open and porous soil, so that the actual contribution to the underflow must be considerable. If the gravels beneath the plains were not so open, so deep, and so wide, the seepage waters would be obliged to seek relief in surface streams, but the underground conditions are such that ample drainage is offered by porous beds of gravel several hundred feet in depth. Even small surface streams, such as Bear Creek and White Woman Creek, are no exceptions to this statement, for these streams entirely disappear as sur |