AGRICULTURAL ENGINEERING. 93 



may V)e obtained, are described. These are the Lewis basin, on the Snake Kiver, 

 l>et\veen Glenn.s Ferry and Weiser; the Otis basin, in, the extreme northea.-tern part 

 of Harney County, Oreg. ; the Harney basin, included in the inland l>asin draining 

 into ^Malheur and Harney lakes, and the Whitehorse basin, in the southern part of 

 Whitehorse Valley. 



The legal restrictions which sliouM i-ontrol the construction and use of artesian 

 wells arc pointed out an<l the text of the Washington law relating to this sul)ject is 

 given. 



Duty of -water in Montana, S. Fortiek {Mdidana Sla. HkI. ,/.;, p/t. .',.',, fi(/x. .',i!]. — 

 This is the second of a series of farmers' bulletins on irrigation an<l includes a sum- 

 mary of results of studies made in cooperation with the irrigation investigations of 

 this Office. The liuUetin defines "duty of water," discusses methods of measuring 

 duty of water, and conditions affecting it, viz, lo.sses in conveyance, climatic condi- 

 tions, system of fixing time rotation, manner of paying for water, judicial decrees 

 for excessive amounts, cultivation ami grading, kind of crops, manner of irrigating, 

 character of soil and subsoil, ground-water level, and configuration of the surface of 

 the land; and gives tabular statements accompanied ])y diagrams showing the 

 oljserved duty of water under laterals in 4fi different cases and under canals in 8 

 different cases. The average iluty under laterals was 142 acres for each cubic foot- 

 second of water, or ;>.7 acres per miner's inch. The duty under canals was consider- 

 ably less, about 2.5 acres, due to losses in conveyance. 



Water resources of Molokai, Ha-waiian Islands, W. Linik;rex ( Water Suppli/ 

 (ind Irrlg. J'lijxis, I'. S. deal. Siirvi'ji, Xi>. 77, jip. G2, }>h. 4)- — This report is based on 

 ol)servations made in 1900 and deals with the water supply in its relation to the 

 decrease (jf the forested area, grazing, and other conditions. Tlie prol)lems of water 

 conservation and utilization are discussed and it is shown that they are '" rather <iiffi- 

 cult and involved, but are similar in many respects to those of the arid West, 'the 

 solution being found in combined systems of storage, water-power <levelopment, use 

 of the power in pumping, the construction of wells, collecting tunnels, and the 

 economical employment of various devices for lifting water." The topography, 

 geology, soils, climate, vegetation, agricultural jiossilnlities, etc., of the island are also 

 briefly discussed. 



"The soils of Molokai are similar to those < if the other islands of the Hawaiian 

 group and are usually of great fertility. They may be divided into residual and 

 sedimentary soils. 



"The resiilual soils result from the gradual decomposition of the basaltic lavas 

 and are usually deep red, very rich in iron and in snlistances necessary for plant 

 growth. 



"Tlie sedimentary soils are partly of a deep-red color, partly dark brown, and not 

 very different in character from the residual soils; they consist, in fact, of the same 

 substance merely transported and redeposited. In a few places along the immediate 

 coast line are small areas covered by coral sand, consisting largely of carlionate of 

 lime, usually more or less mixed with detritus from the hills. 



"The we.'jf end of the island contains a very great amount of good, smooth land, 

 with excellent soil. . . . 



"The finest body of agricultural land on the island is situated in the great gap, 

 and has an area of about 14,000 acres. The principal problem of the water supply 

 of the island is how to l)ring the water from that part which receives an abundant 

 precipitation to this arid portion containing the rich soils." 



The rainfall on the northeasterly portion of the island and at all points over 2,500 

 ft. high is abundant, reaching 100 ins.; the west end and south coast are dry. 



The sources of water supj>ly which are discus.se<l include springs, running streams, 

 and wells. Kstimates of the total amount of water available are tjiven. 



