Geology.—There are many unusual geolog ical phenomena in Idaho. The °City of Rocks° in Cassia County is as strange as, and but little less magnificent in scale than, the Garden of the Gods in Colorado. A thousand homes in Boise, the capital city, and the great Natatorium are heated by natural hot water from springs. Some of the cities obtain their summer water from springs at almost freezing temperature; in winter they obtain their water from other springs at F. Near Richfield in Lincoln County is an ice cave in the lava beds with an ice dome that thaws out in winter and freezes in summer. There are many farms upon which cellars have been dug and deep wells have been bored for domestic water from which come streams of very cold air that is used for refrigerator purposes. There are hot mineral springs on the upper Salmon and Hood rivers many along the course of the Snake River, and in southern Bannock County there are soda and other mineral springs noted for their medicinal properties. The magnificent cataracts of the Snake River are not surpassed in grandeur in the United States. The Shoshone Falls are 46 feet higher than those of Niagara. In central Idaho there are a number of streams that are °lost°— that, crystalline up to the last, sink away into the desert and disappear. In the very tops of some of the highest mountains are beautiful fresh water lakes fringed with tall pines and fir. Great lava planes extend along the Snake River Basin in width from 10 to 60 miles. These are of relatively recent overflow as evidenced by the numerous geysers and hot springs. They are rich in various fossils.
Agriculture.— There are considerably over 6,000,000 acres of land in Idaho under cultiva tion. There are numerous areas of irrigated and dry farm land on the alluvial bottoms and upon the bench lands of the small and large valleys included within the Rocky Mountain portion of the State. In Idaho, agriculture may be considered under three separate divisions, namely: humid farming, dry farming and irri gated farming. The humid section comprises the northern part of the State, where 67 per cent of the crop is wheat. Great areas of logged-off lands are now being put under cul tivation and are specially adapted to the grow ing of clover. The chief crop in the dry-farm ing region, the southeastern part, is wheat raised by intensive cultivation. By far the greater proportion of the agricultural land, however, is found in the great intermountain plateau along the course of the Snake River where the largest irrigation systems in the country are maintained. These embrace 5,003, 833 acres with canals aggregating 10,491 miles in length, and constructed at a cost of more than $90,000,000. These canals are assured an abundance of water by great dam and reservoir systems, among which are some of the largest and best in the world. The Jackson Lake reser voir on the head waters of the south fork of Snake River is one of the largest in the United States. The Arrowrock dam, storing water for irrigating 240,000 acres of land, is the highest dam in the world. The average yield of wheat per acre here is 26.6 bushels; of oats, 40.6 bushels. Idaho produces more alfalfa than any other State in the Union of equal acreage, the yield for 1917 being approximately 1,500,000 tons. An average yield of nearly three tons per acre is obtained. Idaho has about 140,000 acres of orchard. Her apples have won some of the greatest horticultural honors known. Idaho prunes are the finest in the world.
Stock Idaho's stock growing has increased almost in keeping with its increased growth in agricultural development and popula tion, chiefly due to available public range and wise Federal supervision of the extensive forest reserves on which hundreds of thousands of beef cattle and sheep graze during the summer season. There is ample winter provender on
the great alfalfa farms of the Snake River valleys. In 1917 Idaho had nearly 500,000 beef cattle and 3,250,000 sheep. The dairy industry is growing rapidly. In 1918 there were about 140,000 much cows in the State.
Forests.—Although lying partly within the arid belt, Idaho is well forested. Approxi mately 20,000,000 acres or 37 per cent of the total land area of the State is forested. Ample provision is made for the protection of the forested area by the fact that out of the total of 129,000,000,000 feet board measure, 71,000, 000,000 feet or 55 per cent is included in the national forests, leaving 50,000,000,000 feet pri vately owned and 8,000,000,000 otherwise held by the government or State. In area about 90 per cent or 18,000,000 acres of the forest is under national control. Much of the area con tains immature stands which have not yet reached the producing stage but will repay protection. The large white pine forests of northern Idaho are among the most valuable in the United States. Lumber production is increasing rapidly, the cut being mainly soft woods, western pine, white pine, larch and Douglas fir.
The following table gives the names of the national forests in Idaho, area, headquarters of supervisor and last proclamation date effective : Sugar City, Lincoln, Blackfoot, Burley, Twin Falls and Rupert, produced 102,000,000 pounds of sugar in 1917. Another factory was built at Shelley in 1917. Others are now in course of construction. The chief manufactured products are lumber, beet sugar, concrete, packed meats and flour. Large fruit evaporating plants were erected and operated at Meridian and Payette in 1917.
Mining.— Idaho is the largest lead-pro ducing State in the Union. The total produc tion of lead from Idaho's mines in 1917 aggre gated 395,883,000 pounds. With an output of 12,496,017 ounces of silver in 1917, Idaho ranks a close second with the other principal produc ing States of the Union. The zinc mines of Idaho produced 96,123,000 pounds of this metal in 1917. The consolidated Interstate-Callahan mine of the Coeur d'Alene district ranks third among the individual producers of the United States. Copper mining is of less importance, there being a total yield of a little over 7,000,000 pounds in 1917. Gold placer mining was the original source of mining activity in Idaho. The State is credited with a total yield to date, since the original discoveries at Pierce City, of $200,000,000 in placer gold, which was mostly derived from mountain basins in the central granite batholith formations. The placer in dustry is now at a low ebb which is due to the practical ground exhaustion of the larger mines. Idaho produced, in 1917, 41,326 ounces of fine gold. Among the rare metals that are known to exist in Idaho are tungsten, molybdenite, Manufacturing has more than kept pace with the growth of the State in population. Idaho has some of the largest lumber mills of the world. The Potlatch with a daily capacity of 750,000 board feet of lumber in a 24-hour run is considered the largest and the Boise-Payette with a capacity of 500,000 feet a close second. The State has an abun dance of water power available for use in manu facturing. Idaho claims the establishment of the first commercial potato flour factory in the United States. It is located at Idaho Falls. Idaho's six beet sugar factories, located at nickel, tin, antimony and quicksilver. Idaho possesses the richest resources of phosphate rock in the world, located in the southeastern part of the State. Its resources of the com moner mineral substances in the form of fire clays, Portland cement, etc., are practically in exhaustible.