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amount of water or increase of speed in this portion the stream may cut a gorge in the broad plain it had previously formed and leave the former plain terraced above its These are but a few of the observations which may be made upon almost any runing stream and which will be seen to typity and interpret the behavior of all streams and rivers.

Considering again the effect of the continental we sheet and its deposits it may be seen that previous systems of drainage must have been profoundly modified by the filling m of former river and lake beds and that new systems of dramage must have been Satis in many cases Records of former SUGUNEV SAXONs may be observed hy days @@ SANTAN ON, Pier gorges and Mir Nucha acute er danne over 4 \. Ngo

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Turning from the mantle of drift to consideration of the solid rock beneath, one finds that it calls for only a further application of the principles which have just been considered. A large proportion of the rocks of the earth's crust are made up of layers or strata showing deposition by water and hence called stratified rocks. An area of sandstone differs from a bed of sand simply in being more firmly consolidated either by cementing waters or the pressure of overlying layers. The bank of drift represented in the cut previously noted would, if consolidated into rock, form what is known as a conglomerate or pudding stone. Most limestones represent deposits formed by marine life, such as mollusks, corals, etc. Of such deposits forming at the present day the best illustrations are to be seen along coral reefs or in con sands. Such condimx ve been nearly reproduced in tremeso have formed the great limeSoreles dance States

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INCLINED STRATA, NEW YORK.

turned over. Such dislocations must come

from earth movements of greater or less extent, which also caused fracturing and fissuring. In such earth movements some strata would go up, others down, and various readjustments would take place. Such dislocations are always more extensive and violent in a mountain region and here, therefore, is the greater opportunity for finding valuable mineral deposits, since the fracturing and fissuring affords facilities for the movement of hot waters in which gold and other metals may be held and by which they are laid down.

may be able to make on the outcrops met,
it will usually be found when the survey of
the area is finished, that some system or
course of arrangement of the rocks has
been discovered, such as is exhibited by the
series of Ms in the accompanying cut.
When the formations are thus mapped fur-
ther study in detail can be given each par-
ticular one. In all such observations one
should, of course, be careful to distinguish
the rock in place from what may be simply
boulders protruding through the soil and
having no connection with the rock be-
neath.

Further, care should be used to distinguish effects of erosion from those of uplift. The carving of most of the prominent features in a locality, say a mile square, will be the result of erosion which has worn away the softer portions and left the harder standing in relief rather than the pushing upward of the higher portions by some force acting beneath.

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In seeking to follow any given rock formation through a region, the mantle of soil and vegetation or the presence of forests and bodies of water to a large extent hide the underlying rock from view in any but a desert country. To overcome this difficulty the geologist must learn to take advantage of all exposures, or "outcrops," as they are called, and draw his conclusions from them. Every railroad cut or excavation for highways, every quarry or even diggings for the foundations of buildings, every well, bored or dug, will afford clues which he must use to the utmost to enable him to trace out the order of the rock formations. Even if the country is uninhabited so that no such aids are at hand, a considerable knowledge may be gained by a systematic reconnaissance. This may be carried on after the method adopted by governmental surveys illustrated in the accompanying sketch. This represents a plot of a given area, over which are drawn imaginary north and south lines at equal distances. If, now, one paces over the area, following these lines in succession marking in his notebook (in which the area is thus plotted) all the observations he

and

It would be impracticable to give here directions which would enable one to distinguish in the field minerals of economic value. Appearances to the untrained eye are usually misleading, the most showy species being in general the least valuable for economic purposes. Thus the brass yellow pyrite, worthless when only disseminated in small grains, is often mistaken for gold, and even scales of glittering mica appearing yellow in the sunlight, were shipped in quantities to England as gold, by the early explorers of Virginia. The vast ma

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jority of profitable gold ores, if the placer or stream ores be excepted, can be said to exhibit no gold whatever to the naked eye. In general, minerals likely to prove of value as ores, are opaque and have what is called metallic luster, although there are important exceptions to this rule. Color is a criterion of very little value, unless intelligently used, as the same mineral may appear of various colors, and the quantity of an ingredient required to color a mineral mass is very small.

The pebbles found on beaches and in streams largely consist of some form of quartz, since this mineral is hard and is left behind after its associated rock is worn away. The different colors of these pebbles are due generally to staining by iron in various stages of oxidation.

When pebbles of peculiar form are found it should be remembered that such forms may be given by differences in the resistance to wear by the different minerals of which the pebble is composed, and that only in the rarest instances can they be "petrified" objects. Petrifaction as the term is generally understood, i. e., meaning a once living substance, "turned" to stone, almost never takes place in Nature. The processes of decay are too rapid and the conditions permitting

deposit of mineral substances

preserved to a certain extent, but the chances of their ever being replaced by mineral matter and so of becoming truly petrified are exceedingly few.

The parts then of living animals which are preserved as fossils and from which our knowledge of them is drawn are such as were composed of mineral matter in life, and include bones and teeth of vertebrates and the shells and internal skeletons of mollusks, corals, etc. Actual fossils may also consist of casts or impressions showing the form of the living animal or plant which has been preserved by the mud in which the object was buried.

A form of mineral aggregate which is easily liable to be mistaken for a petrifaction is that known as a concretion. These may be formed in soils of all kinds, but

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too rare to allow such occur- PINNACLES 350 FEET HIGH PRODUCED BY EROSION OF SURROUNDING

rences. Wood is a substance which more commonly than any other petrifies, and its

form and structure are often perfectly preserved. In petrified wood each particle of organic matter has been replaced by a particle of mineral matter, and thus the change has been made complete. The tissues of dead animals also sometimes turn to the form of fat known as adipocere, which may be preserved for a longer or shorter time, and the tissues of plants may become carbonized to form coal, but these include practically all the petrifactions possible. The human body has never been preserved in Nature in any form maintaining its substance and outline as in life, and all purported instances of such an Occurrence are fictitious. In a dry climate the tissues may desiccate upon the bones so as to be

STRATA, GRAND JUNCTION, COLORADO. (Photo by H. Wm. Menke.)

more commonly in clays and may be made up of carbonate of lime, iron pyrite or other minerals. They are formed in place in the clay bed or other stratum by the tendency which their mineral substance has had to draw together from among the surrounding strata. These concretions usually take ovoidal forms, but may be cylindrical or very irregular and may be compact or hollow. Sometimes after being formed, they crack open and the cracks become filled with another mineral of different color or hardness, or both. Such, especially after weathering, often assume very grotesque forms, whose origin would be puzzling were not one able to refer them to concretions.

GREAT BRITAIN.-There was great rejoicing in Great Britain and throughout the Empire over the close of the Boer war. Thanksgiving services were held in St. Paul's Cathedral and in many churches. King Edward congratulated Lord Kitchener, who received a Parliamentary grant of £50,000 in appreciation of his success in conducting the war and in concluding the peace negotiations.

By the middle of June all, or nearly all, of the fighting burghers, some 16,600 (11,225 in the Transvaal and 5,395 in Orange River Colony), had surrendered. Generals Botha,

AMERICANS IN LONDON.

home as invalids (the great majority recovering). The total number of deaths in South Africa was 21,942, as indicated in the following table:

Town Governor Woodroof, with Mrs. Woodroof, entertaining a party of Americans at the Ascot Races (From a photograph taken for THE WORLD TO-DAY by N. Lazarnick.)

Killed in action

Died of wounds Died in captivity Died of disease Accidental deaths

De Wet and De la Rey were thanked by Kitchener for their zealous efforts to promote harmony and good-feeling among the Boers. Preparations were at once made for the return of Boer prisoners. The total number of prisoners, as stated by Mr. Brodrick in the House of Commons (June 3), was 25,555, distributed as follows: Cape Colony, 1,055 burghers; Natal, 855; St. Helena, 5,679; Bermuda, 4,543; Ceylon, 4,939; India, 8,484.

Totals ...

...

...

Officers. Men.

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Of invalids sent home who died there were 1,580, making the number of deaths in all 23,522. Casualties reported in June are not included in these figures.

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The casualties on the Boer side are not known. The casualties of the British, reported up to June 1, 1902, amounted to 97,477, including 75,430 men and officers sent

The cost of the war in money, including the estimates for the year ending March 31, 1903, is about £222,000,000 ($1,100,000,000). Of this sum £159,000,000 is borrowed. The increase of taxation in the United Kingdom on account of the war is £34,000,000 for the current year; and of this the increase of the income tax is said to be £17,600,000. There has been much opposition to the corn tax, and by some it is said to be doomed. However, the government is slow to abandon it or hold out hopes of its speedy abolition, notwithstanding the free trade leanings of Sir Michael Hicks-Beach and other ministers. The bread tax falls heaviest upon the poor. means higher prices for necessaries to a large class of working people.

It

Lord Milner, who is High Commissioner for South Africa, took the oath of office as British governor of the Transvaal, on June

22.

The American shipping trust has caused much alarm, not only in Great Britain, but in France and Germany.

Elaborate preparations for the coronation were made, but owing to the King's severe illness it was indefinitely postponed. While his life hung in the balance, not only his subjects, but Americans and the people of other nations waited in anxious suspense, fearing the worst. The crisis was reached on the day set for the coronation, June 26. It was successfully passed, and Edward's recovery was therefore regarded as possible and even probable. His illness brought out forcibly the fact that Britons the world over are strongly attached to their sovereign.

The King's death would have brought a loss estimated at $21,000,000 to the insurance companies of England. The policies

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