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which separates the waters that flow north-west into the German Ocean from those that flow north into the Baltic, and south-east into the Black Sea, was presented to view-executed almost as beautifully as an engraving. A dozen wrinkled strokes, made in the twinkling of an eye, represented the head waters of the great rivers which flow in different directions from that mountainous range; while the children, almost as eager and excited as though they had actually seen the torrents dashing down the mountain sides, cried out, Danube, Elbe, Vistula, Oder,' &c. The next moment I heard a succession of small strokes or taps, so rapid as to be almost indistinguishable, and hardly had my eye time to discern a large number of dots made along the margins of the rivers, when the shout of 'Linz, Vienna, Prague, Dresden, Berlin,' &c., struck my ear. With a few more flourishes, the rivers flowed onwards towards their several terminations, and, by another accession of dots, new cities sprang up on their banks. Within ten minutes from the commencement of the lesson there stood upon the black board a beautiful map of Germany, with its mountains, principal rivers, and cities, the coast of the German Ocean, of the Baltic and the Black Seas, and all so accurately proportioned, that I think only slight errors would have been found, had it been subjected to the test of a scale of miles. A part of this time was taken up in correcting a few mistakes of the pupils, for the teacher's mind seemed to be in his ear as well as in his hand; and, notwithstanding the astonishing celerity of his movements, he detected erroneous answers, and turned round to correct them. Compare the effect of such a lesson as this, both as to the amount of the knowledge communicated, and the vividness, and of course the permanence of the ideas obtained, with a lesson where the scholars look out a few names of places on a lifeless atlas, but never send their imaginations abroad over the earth; and where the teacher sits listlessly down before them to interrogate them from a book in which all the questions are printed at full length, to supersede, on his part, all necessity of knowledge." -MANN'S Educational Tour in Germany.

6

The following from an article in the Quarterly Review,' on Physical Geography, affords an instructive hint.

"Of the thirty-eight millions of square miles, forming in round numbers the total area of land, nearly twenty-eight millions lie to the north of the equator; and if we divide the globe longitudinally by the meridian of Teneriffe, the land on the eastern side of this line will be seen greatly to exceed the western: another manner of division into two hemispheres, according to the maximum extent of land and water in each, affords the curious result of designating England as the centre of the former, or terrene half-an antipodal point near New Zealand as the centre of the aqueous hemisphere. The exact position in England is not far from the Land's End; so that if an observer were there raised to such height as to discern at once one half of the globe, he would see the greatest possible extent of land; if similarly elevated in New Zealand, the greatest possible surface of water.

"An increase of land above the sea between the tropics raises the mean temperature, in higher latitudes depresses it; and every such vicissitude must be attended with some corresponding change in the nature and conditions of organic life."

APPENDIX (B.)

The arithmetical constants given below, with the tabular matter on the different subjects to which the tables relate, will, in the higher class of schools, be found of great service. Some of the walls of the class-room in the King's Somborne School are plastered, and the following matter, in a tabulated form, written upon them, in letters and figures of about an inch in size. They not only suggest observations during the progress of a lesson connected with the subject of them, but they accustom the teacher to something like arithmetical accuracy in making such observations, and enable the children to form ideas of a definite kind, and make the subjects perfectly intelligible; in fact, knowledge communicated in this way makes them close and accurate reasoners, and it is astonishing to see how much they get interested in it. These tables also suggest numberless questions in arithmetic which may be given by a teacher. In giving them here, it is merely to suggest the same thing to others, and in schools, where such information is not a part of their teaching, tabular matter, connected with the ordinary weights and measures-the number of cubic inches in a solid yard, in a quart, and other measures, might supply its place on the walls of the schoolroom.

From Table I.—In comparing the rapidity of the motion of a cannonball with that, for instance, of the swallow, the teacher would point out the necessity of reducing them to spaces passed over in the same time, when it will be found that the cannon-ball moves at the rate of more than 1300 miles per hour, the swallow, 90; that one is a velocity so great that the eye cannot see the object moving; that there is an intermediate velocity between the two, with which, if the ball moves, it ceases to be invisible, and that it will be gradually reduced to this before its motion ceases after striking the ground-which is called a spent ball; that the flight of a bird may be supposed to be so increased, as not to be seen in passing from one point of space to another, &c.

The outline of Table VIII, which is only partially filled up, would suggest many observations of a meteorological kind-why points of equal temperature on the surface of the earth do not follow the simple rule of distance from the equator; how affected by sea, land, mountains; accounting for the zig-zag nature of isothermal lines, &c. It would also be found very useful to draw on the ceiling of the school- or class-room lines running in the direction of the four cardinal points, with a line representing the magnetic meridian in degrees, and the magnitude of the angle of variation written between them.

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Most rapid flight of a swallow, about 80 to 90 miles per hour.* TABLE II.-Specific Gravity, Distilled Water = 1.000.

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These inches of mercury measure also the elastic force of the vapour of water at the same temperature.

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*Tables III, IV, V, VI, from Lardner's Cyclopædia, volume on Heat,

TABLE VII.

Linear Dilatation.

Of Solids by Heat.

Dimensions at 212° of a bar whose length at 32° is 1.00.*

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