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questions in this country is concerning the future of the Mississippi alluvial plain, if the spring floods should become greater, through the cutting of forests around the headwaters of any large tributaries or for any other reason.

Mr. James L. Greenleaf in the American Journal of Science for July 1896, says it is fortunate for dwellers in the lower Mississippi that floods in all the tributaries do not come at the same time. Were the floods simultaneous he concludes that the great river would have to carry 3,000,000 cubic feet of water per second to the Gulf. Owing to the fact the Ohio flood usually leaves the river before the arrival of the Missouri flood the largest flood discharged into the Gulf probably does not exceed 1,800,000 cubic feet per second.

The Question of the Oxus.-Geographers have long discussed the possibility that once the Oxus or Amu Daria River flowed west into the Caspian Sea instead of north into the Sea of Aral as now. If there be such a path and it could once more by artifice be made a water highway, a great commercial route well into the centre of Turkestan would be established.

The economic importance of such a possibility is very great. A Russian expedition started in September 1896, to explore this country to find out if a water route along this supposed path would be more or less costly than a railway.

Southeast of the Sea of Aral in the same basin is the Lake Sari-Kamish. This basin is separated by a divide of considerable height from the basin of the Uzboi; which latter basin has long been considered the former outlet of the Amu Daria, to the Caspian.

Recent work by Russian geologists, reviewed in the Annales de Géographie for October 1896, has shown that owing to the height of the divide spoken of above it can not be presumed that the Amu Daria flowed along the path of the Uzboi, and incidentally the author remarks that the making of such a water route as is suggested is impractical. The author considers the Uzboi depression as a torrent valley cut by the water rushing out from the Aral-Sari-Kamish basin, when the lowering of the whole country allowed this region to be drained into the enlarged Caspian Sea which then extended to the edge of plateau of Kara-Kum.

Pacific Ocean Currents.-"Dr. Cäsar Puls contributes an elaborate discussion, based on original records, of the surface temeratures and currents in the equatorial belt of the Pacific Ocean to the Archiv der Deutschen Seewarte (Hamburg, XVIII., 1895, 1-38 with 12 monthly charts). The chief interest attaches to the equatorial counter current, which maintains its eastward course all across the ocean between the wind-driven, west-flowing equatorial currents. on the north and south, the latter being much the stronger of these two. The north equatorial current, from 9° to 20° N., is strongest in March; it is not altogether supplied at its east end by the weak southward current along our west coast; it receives much water from the counter current which turns northwest at its east end, and not southeast, as ordinarily mapped. At the west end of the north equatorial current, part turns north to flow past Japan and a lesser part south to join the counter current. The greater south equatorial current, from 12° S. to 5° N., is strongest in September, and has its highest velocity along its northern margin, sometimes over 100 nautical miles in 24 hours. It is largely supplied by up-welling water along the west coast of South America, where the wind blows off-shore; the Humboldt surface current is not sufficient to feed it. Part of this great equatorial current turns south before reaching the Solomon Islands; the rest passes on north of New Guinea and turns sharply back at the 'root' of the counter current, except from December to May, when this branch is turned back on itself by the northwest monsoon then and there prevalent, forming a short counter current south of the equator. The north counter current, extending all across the ocean is said to be much influenced, but not produced, by the winds. Near its west end it is favored for three-quarters of the year by the southwest monsoon; and from July to October, when it is, as a whole, strongest and broadest, its east half is favored by the narrow belt of monsoon winds there and then occurring. It is narrowed and weakened in our winter, when these favoring winds are wanting, and from January to March, under the extended northeast trade, it may be stopped or locally reversed; but where and whenever these adverse winds weaken or shift, the current reappears, and sometimes with increased strength. Yet, as a whole, it is regarded as a compensation current, dis

charging eastward the excess of the wind-driven south equatorial current, which has no sufficient escape at its west end.”—Science.

Alaska.—The present great interest in the mineral resources of Alaska makes the following, notes taken in part from an article in the Scottish Geographic Magazine for November, 1896, most helpful.

All the region to the north of the 56th parallel and to the west of a line three marine leagues from the coast; and above about 61° to the west of the 141st meridian, belongs to the United States. This region is rich in gold and other ores, and the workings on the Upper Yukon and at Juneau are well known. Recent work by the commission establishing the boundary line between Alaska and the British Possessions shows that the larger area of great mineral value probably belongs to Canada.

Taken as a whole, Alaska has more seacoast than all the rest of the United States on the Atlantic and Pacific, not including the Aleutian Islands. The principal means of entering the interior is by the great Yukon river, which usually opens for navigation in June, and is 8 miles wide at Fort Yukon. The main stream is navigable 850 miles, and enters the sea through several mouths, no one of which is more than 8 feet deep. Indeed the Yukon is to be counted as having one of the famous deltas of the world. "For hundreds of miles from the sea the Yukon flows through low level tundras, or mossy morasses resting upon a foundation of clay. The shifting current of the river eats away the shores on either side with astonishing rapidity, the dull thud of caving banks is constantly heard by the traveler. Stepping upon the shore the explorer must jump from hummock to hummock or wade around from knee to waist deep. In many places the ice never disappears within a few inches of the surface, being protected from the rays of the sun by a non-conductive layer of sphagnum.

"Wherever there is a slight elevation of ground in all this watery waste the wretched natives have located their villages; the dwellings consisting of excavations in the ground roofed over with mounds of sod. Here they fish during the summer and hunt the musk and moose in the winter."

Indiana.-"Outside the New England group there are but five

Her 36,000 There are no

States in the Union smaller than Indiana. Although one of the lesser States, Indiana has very little waste land. square miles are well watered by streams and lakes. mountains within her borders and no high hills, except those along the Ohio River. Almost all the State is situated in the Mississippi Valley. The soil is fertile and adapted to all the cereals and grasses grown in this climate. Though touched on the north by Lake Michigan and on the south by the Ohio River and on the west by the Wabash, yet the State is penetrated by no navigable stream.

Our State is rich in minerals, coal, building stone, iron, natural gas and oil. The extent of the gas-fields is said to exceed those of Pennsylvania and Ohio combined. Our coal fields cover 7,000 square miles. Coal is found in twenty-four of our ninety-two counties. Our mineral springs are unrivaled for medicinal purposes. Indiana has extensive quarries of excellent limestone and sandstone. This stone has been recently used in some of the finest public buildings and residences in the United States.

Three-fourths of the State was originally covered with forests. It required twenty-five years' unrestrained destruction of trees to clear out two hundred thousand farms. About one-fifth of the state is still covered with timber, which is now worth more than the land on which it stands. Our forests contained, originally, all the varieties native to this climate. Next to the soil and minerals, timber was, perhaps, Indiana's greatest source of natural wealth.

The population of the State in 1890, was 2,300,000, and our State now ranks eighth in the Union, in respect to population. The center of population of the United States is located about fifty miles south of Indianapolis.”—Inland Educator. Dec., 1896.

REVIEWS.

The Century School Supply Company, of Chicago, is selling a series of geographical illustrations, of which two transparencies are especially helpful and suggestive. These show the seasonal positions of the planets and the changes of the tides in reference to the relative positions of sun, moon and earth. They can be procured apart from the rest of the set.

The remaining parts of the set are, on the whole, more harmful

than helpful to the child, for they present features not true to nature and congregated in an impossible way in one small region.

The attempt is made to illustrate geographic definitions by taking imaginary excursions, a method now out of date in the best schools. We need to train the eyes as well as the ear, but let our attempts be true to nature and not productive of conceptions worse, perhaps, than none.

Man and his Markets. A Course in Geography. By LIONEL W. LYDE, M.A. Pp. x+186. Illustrated. The Macmillan Co. 1896. Under the separate chapter headings of "Environment," "Birth of a City," "Bread and Milk," "Flesh and Fish," "Coal and Wood," etc., Mr. Lyde has grouped together a mass of suggestive material that should be helpful to the teacher of comparative or economic geography. The chapter, for instance, on Environment states in a very elementary way some of the effects of natural geographic conditions on peoples. The influence of mountains, indented seashores, plains, deserts, etc., is quite clearly stated, though not in as detailed a manner as one would wish. The conditions favoring the building of a city are summarized so as to be helpful to one who has never tried to bring together in one statement all the more important geographic and social determinants of the development of large centres of population.

Unfortunately there are many instances in which the items given are not strictly accurate and hence the book cannot be used in its entirety. The illustrations are, with few exceptions, of an inferior quality and not at all helpful. Many are drawn from the ideal and not from actual conditions and are worse than useless.

The book would be of a fair amount of assistance to a teacher, but is not of a kind to be placed in the hands of the pupils.

The Werner Introductory Geography, price 55 cents; and The Werner Grammar School Geography, Parts. I. and II. Price $1.40. By HORACE S. TARBELL, A.M., LL.D. Werner School Book Company. 1896.

The Introductory and Grammar School Geographies recently published by the Werner School Book Company, can hardly be said to "leave nothing desired;" but it can truthfully be said that

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