FACTS ABOUT THE EARTH.

The total area of the earth is about 197,000,000 square miles, and its total population 1,626,000,000. The area of the water of the earth is about 145,000,000 square miles. The area of the land of the earth is about 52,000,000 square miles.

'The figures of population, excepting those for the United States, are taken from the Year Book of the Bureau des Longitudes. Including all islands in the Eastern Indian and Southern Pacific oceans. *Including population in the Dutch East Indies. The largest states, comprising parent country and colonies or possessions, are:

According to the number of inhabitants, the countries range as follows:

British Empire and Colonies....403,000,000 |

China

50,000,000

Austria-Hungary

.350,000,000 Netherlands

44,000,000

The longest rivers in the world are: In Europe, Volga, about 2,200 miles; in Asia, Yenisei, about 2,700-3,000 miles, and Yang-tse-Kiang, about 3,000; in Africa, Nile, about 3,240 miles; in North America, Mississippi and Missouri, 4,300 miles; in South America, Amazon and Beni, 4,000 miles; in Australia, Darling, more than 2,345 miles.

The largest lake in the world is Lake Superior. It covers an area of 31,200 square miles and has a mean depth of about 475 feet.

The greatest cataract in the world, surpassing by far Niagara and Zambezi Falls, is on the Ignazu River, which partly separates Brazil from Argentina, one thousand miles by boat from the nearest settlement. The precipice over which the river plunges is 210 feet high, that of Niagara being 167 feet. The cataract is 13,123 feet wide, or about two and a half times as wide as Niagara. It is estimated that 100,000,000 tons of water passes over Niagara in an hour; a like estimate gives the Falls of Ignazu 140,000,000 tons.

The oldest city in the world is Damascus, in Syria. The exact date of the founding of this city, once so famous for iis manufacture of silks, jewelry and blades, is

not known, but it is said to have been begun by a greatgrandson of Noah, and prob ably is 4,200 years old. Next comes Athens, the capital of Greece, which is about 3.458 years old-older than any other European city. Peking, the capital of China, is said to be about 3,000 years old. Jerusalem, which was a Jebusite city in the days of Abraham, is 3,000 years old at least.

The coldest country in the world Is Werchojansk, in Siberia, longitude 133 degrees 51 minutes east, latitude 67 degrees 34 minutes north, where a lowest temperature of minus 90 degrees Fahrenheit has been observed, and the mean of January is minus 48 degrees Fahrenheit. The country is inhabited by about one hundred and five thou sand persons of the Jakut and Lamat races.

GEOLOGICAL STRATA AND ERAS.

The history of the earth is divided into five eras with corresponding rock systems: 1, Archaean or Eozoic (dawn of life), embodied in the Laurentian system; 2, Palaeozoic (old life), embodied in the Palaeozoic or primary system; 3. Mesozoic (middle life), recorded in the secondary system; 4. Cenozoic (present life), recorded in the Tertiary and Quaternary systems, and 5, the Psychozoic (Era of the Mind), recorded in the recent system. These grand divisions, with the exception of the last, are founded on an almost universal unconformity of the soil.

The history of the earth is otherwise divided into Seven Ages, founded on the culmination of certain great classes of organisms. These are:

1. The Archaean or Eozoic Age, represented by the Laurentian system of rocks. 2. The Age of Mollusks, represented by the Silurian series of rocks. 3. The Age of Fishes, represented by the Devonian rocks. 4. The Age of Acrogens, or sometimes called the Amphibian, represented by the Carboniferous rocks. The Age of Reptiles, represented by the secondary rocks. 6. The Age of Mammals, by the Tertiary and Quatenary, and 7 The Age of Man, by the recent rocks The diagram shows how the ages correspond with the eras:

[The vertical height represents time, the strong horizontal lines separate the ages, the shaded spaces represent the origin of the dominant classes of animals and plants. Thus, for instance, the class of reptiles commenced in the time of Carboniferous rocks.]

The subdivisions of eras and ages into periods and epochs are founded on less nonconformity in the rock system, and less conspicuous changes in the life system. The names and periods are often, and of epochs are nearly always, local,

and therefore different in different countries. The table represents, as far as periods, the classification used in America.

Glacial

Pliocene

The total thickness of all the strata known amounts to 72.000 metres (44.74 miles), of which about 1,000 metres belong to the Cenozoic (recent life) era, 3,000 to the Mesozoic (middle life). 30,000 to the Palaeozoic (old life), and 38,000 to the Eozoic (dawn of life) eras. From these figures the approximate relative duration of the eras is calculated.

THE AGE OF THE EARTH.

In a publication issued in July, 1910, by the Smithsonian Institution, the age of the earth was estimated by Frank Wigglesworth Clarke and George F. Becker, of the Geological Survey, as "not above seventy million or below fifty-five million years." The age of the earth always has been a subject for discussion among men of science, and largely without any definite agreement among the representatives of the different branches of studies on account of the different points of approach. The more recent discussions as to the earth's age have placed the time as follows: Lord Kelvin, in 1862. 20,000,000 to 400,000,000 years, with a probable 98.000.000 years; in 1897 Lord Kelvin revised his figures to 20,000,000 to 40.000,000 years; Clarence King and Carl Varus, in 1893, 24,000,000 years De Lapparent, in 1890, 67,000,000 to 90,000.000 years; Charles D. Walcott, secretary of the Smithsonian Institution, in 1893, maximum age, 70,000,000 years; J. Joly, In 1899, age of the ocean, 80,000,000 to 90,000,000 years, and W. J. Sollas, in 1909, age of the ocean, 80,000,000 to 150,000,000 years.

THE RACES OF MANKIND.

While from the researches of the physiologist, the anatomist, the philologist and the psychologist the same testimony is obtained as to the specific unity of the human race, ethnology for convenient classification divides men, according to their physical or psychical characteristics, into groups, families, clans, tribes, and, on account of their distribution, these are sometimes named for geographical divisions. In these efforts of classification different schemes have been tried. Linnæus classifies the races according to geographical areas. Dall divides men into three groups: white, black and yellow; Garland, into six races, separating the Dravidians from the other groups. The cranological school founded by the elder Retzius made the shape of the head the basis of classification, and accordingly mankind was divided into long skulled and short, broad skulled races. Blumenthal gives five groups, classified according to the color of the skin Professor Huxley also designated five groups along somewhat similar lines. Morton used the skull as a basis of classification; Haeckel and Broca the hair, and Hale language. The tendency now seems to be to return to the earlier classification and its three greater subdivisions white, black and yellow, or Caucasian, Negro and Mongolian, with the addition of two more subdivisions, red and brown, or American and Malay, Under such plan Blumenthal's scheme of dividing men according to the color of the skin can be used. Under It there are grouped: (1) Caucasian, or white; (2) Ethiopian, or black; (3) Mongolian, or yellow; (4)

American, or red; (5) Malay, or brown. Classified in this manner, the human species presents the subdivisions shown in the following table, as given by Professor Amos W. Butler:

I. Negrillo

II. Negro

III. Negroid

I. Sinitic

II. Sibiric

(1. Libyan

2. Egyptian

13. East African

(1. Arabian

2. Abyssinian
3. Chaldean

Euskarian

Indo-Germanic or Certividic peoples
Peoples of the Caucasus

African or Negro Race.

Traits-Color, black or dark. Hair, frizzly. Nose, broad.

Traits Color, yellow or olive. Hair, straight. Nose, medium.

Traits Color, coppery.

Hair, straight or wavy.

Nose, medium.

[1. Arctic

The Jewish Year Book," just published in London, estimates the number of Jews in the world at 11,625,656, viz., Europe, 8,892,019; Asia, 432,855; Africa, 379,750; America, 1,903,926; Australasia, 17,106.

MOST SPOKEN LANGUAGES-HIGHEST TOWERS AND MOUNTAINS. 55

MOST SPOKEN LANGUAGES.

Chinese is said to be spoken by all the 400,000,000 inhabitants of the Chinese Empire, which would make it the most spoken language. It is, however, an error to speak of a Chinese language, as the dialects spoken in the various provinces of the country differ from each other as much as English differs from Russian. Putting Chinese aside, the most spoken language is English, with 200,000,000 users. Then follow, in millions: Russian, 100; German, 87; Arabic, 55; French, 47-50; Spanish, 45; Japanese, 46; Italian, 38; Malaic, 25; Turkish, 23; Portuguese, 22, and Greek about 4 millions.

The highest masonry bridge is at Constantine, in Algeria, 300 feet above the bed of the Rhumel River (total length of the viaduct, 1,475 feet). The second highest bridge is in the Swiss Canton of Grisons, nearly 500 feet long, crossing the gorge of the Albula, 292 feet above the stream. The third is over the Lajus at Ronda, in the Spanish province of Andalusia, 230 feet long and about 274 feet high.

THE LONGEST AND MOST IMPORTANT BRIDGES OF THE WORLD.

The height of few mountains has been ascertained with surveying instruments. Those which any one actually ascends are usually measured by the barometer, which is not infallible, and which at different times may give dissimilar results. The elevation of other mountains, which no explorer has yet climbed, is estimated by persons who scrutinized them from adjacent peaks. Here, again.