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river with violent impetuosity, tearing up the earth, and carrying on its surface flaming woods, and every thing it met with in its course, and forming other lakes of fire. The whole extent of ground covered by this fiery inundation, was no less than 90 miles long, by 42 in breadth, or 3780 square miles, the depth of the lava being from 96 to 120 feet. All the time of this great eruption, the whole atmosphere was loaded with smoke, steam, ashes, and sulphureous vapours. The sun was frequently invisible, or, when seen, was of a dismal reddish colour; and the rain which fell through the smoke and steam, was so impregnated with salt and sulphureous matter, that the hair and even the skin of the cattle were destroyed, and the grass of the fields rendered poisonous. Twelve rivers were dried up by this fiery inun

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Vesuvius and Naples

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dation, many lakes were filled up, 20 villages were destroyed, many thousands of sheep and cattle perished, and more than 240 human beings were destroyed. After this eruption, two islands were thrown up from the bottom of the sea, 100 miles south-west from Iceland-one of them three miles in circumference, and about a mile in height, which continued for some time to burn with great violence.

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In an eruption of Vesuvius in 1769, about midnight, a fountain of fire was shot up to an amazing height, casting so bright a light, that the smallest objects were clearly distinguishable at any place within six or seven miles of the mountain. On the next day a most violent report was heard, which shook the houses of the town of Portici to such a degree, that the windows were broken and the walls rent by the concussion of the air; and, in an instant, a fountain of liquid transparent fire began to rise, and, gradually increasing, arrived at length at the amazing height of 10,000 feet and upwards, when its blaze was reflected with awful grandeur from the sea. gentleman, at Sorrento, twelve miles distant from Vesuvius, read the titlepage of a book by that volcanic light.-Mount Etna is the largest volcano in Europe. It is above 2 miles in perpendicular height; it is about 30 miles in a straight line along its declivity to the top, its circumference at its base is above 120 miles, and its crater above three miles in circumference. In 1669, burning rocks, 15 feet long, and 50 in circumference, were thrown to the distance of a mile, and showers of cinders and ashes to the distance of more than 60 miles. A fiery stream burst from the mountain, 14 miles long and 6 miles broad, which destroyed in its course the habitations of nearly 30,000 persons; and, meeting with a lake four miles in compass, not only filled it up, but made a mountain in its place. The quantity of materials thrown out by volcanoes is prodigious. It was calculated that, in this eruption, the matter thrown out amounted to 150,000,000 cubical yards; so that, had it been extended in length upon the surface of the earth, it would have reached nearly four times round the circumference of the globe. The noise emitted by volcanoes has been compared to a mixed sound made up of the raging of a tempest, the murmur of a troubled sea, and the roaring of thunder and artillery, confused altogether. The roarings of Cotopaxi in South America, one of the largest volcanoes in the world, have been heard at the distance of more than 200 miles. Volcanoes are found in every quarter of the world. Forty have been observed constantly burning between Cotopaxi and the Pacific ocean; 20 have been seen in the chain of mountains that stretches along Kamtschatka; and many of them are to be found in the Philippines, the Moluccas, the Cape de Verd, the Sandwich, the Ladrone, and other islands in the Pacific ocean. About 205 volcanoes are known to exist, of which 107 are in islands, and 98 on the great continents. All these grand and terrific phenomena of nature are under the direction and control of the Creator of the universe; and they afford presumptive proofs that man has fallen from his original rectitude, and is no longer in a state of innocence.

Questions on the preceding Lesson.

(1.) What is the nature of a volcano? What part of a volcano is its crater? What substances are thrown out from volcanoes? What appearances generally accompany their eruptions? What are the signs or forerunners of an eruption? What is meant by lava? What appearances does it present, and what effects does it produce? Which are the principal vol

cances in Europe? What is peculiar with respect to Stromboli? Describe the size and situation of Hecla. What preceded the eruption in Iceland in 1783? What extraordinary appearance did this eruption exhibit? Of what did the fire-spouts consist? at what distance were they seen? and to what height did they rise? How long did they continue to burn? How large a tract of country was covered by the burning materials? and what devastations did they produce? What was the depth of the burning stream? What was the appearance of the sun during this eruption? What effects were produced by the rain, and what was the state of the atmosphere ?What striking appearance was beheld during an eruption of Vesuvius? At what time of the day or night was it seen? What happened before another awful appearance? Describe the size of Mount Etna, and state the circumference of its crater. What were the circumstances attending its eruption in 1669, and what effects did they produce ?-(2.) What number of volcanoes has been ascertained? In what countries are they found? How many are in Europe? How many in the mountains of Kamtschatka? What size of stones have been thrown out of Etna and Hecla, and to what distance were they thrown? How many villages were destroyed by the eruption in Iceland? What effect did it produce on the lakes and rivers? and upon animated beings? Were any men and women destroyed? What were the length and breadth of one of the lakes of fire formed by this eruption? Describe the dimensions of the fiery stream which ran down Mount Etna in 1669. To what has the noise of volcanoes been compared? What effect did this noise produce in the town of Portici? At what distance was a gentleman enabled to read by the flame of a volcano? What was reckoned the height of the stream of fire which ascended from Vesuvius? How many habitations were destroyed by the eruption of Etna? and what effect did it produce on a lake? Have any volcanoes ever risen from the bottom of the sea? From what part of a volcanic mountain does the eruption of lava proceed? and does it always issue from the same part? What was the size of one of the islands thrown up from the sea near Iceland? To what distance have sand and ashes been thrown in the eruptions of volcanoes? What is generally the appearance of the sky, and of the luminaries of heaven, previous to an eruption, and during its continuance? At what distance have the sounds of the volcano Cotopaxi been heard?-What is the meaning of the word subterraneous? whence is it derived, and of what words is it compounded? Describe, likewise, the meaning of the words phenomena, summit, devastation, inundation, lava, &c. Point, on the map of Europe, to the situations of Hecla, Vesuvius, Stromboli, and Etna. Point, on the map of the World, to the situations of the other volcanoes mentioned in the Jesson. How many volcanoes are situated in islands? What length of a journey is requisite in ascending to the top of Etna? Under whose superintendence are the operations of volcanoes? and what moral instructions may we learn from their terrific and destructive effects?

The above lesson is compiled from five or six different sources, so as to condense as many interesting facts as possible in one description. The language of the original authors have been altered and simplified, and some original sentences interwoven. It is seldom that a mere extract will be found, in all its parts, suffi

ciently perspicuous and interesting to the young; and therefore it would require a considerable degree of labour and research to arrange and compile a volume or two on the plan proposed. The questions are intended to excite the attention and judgment of the pupil, and the answers are understood to be prepared by him, previous to his reading the lesson along with his class. At the same time, the teacher has it in his power to put to his pupils as many subordinate questions connected with the subject as he may deem expedient, and to illustrate, by familiar descriptions, any objects either directly or indirectly connected with the facts stated in the lesson.-The first twenty-six questions are stated nearly in the order of the lesson; the remaining queries, beginning at No. 2, are intentionally arranged in a dfferent order, to exercise the judgment of the pupil, and to prevent him getting his answers by rote. This arrangement would require to be adopted in almost every lesson. Each lesson should contain a perspicuous description of some well-defined scene or object, the knowledge of which would form a portion of the foundations of useful science. And, were all the ideas comprised in a lesson of this description to be impressed upon the mind of the pupil every day, it cannot be doubted, that in the course of a year, when above three hundred such lessons would be studied, a very considerable portion of useful information would be communicated-far superior in utility and extent to all that has hitherto been acquired by the perusal of Epilogues of stage-players, Speeches in the Roman Senate, Parliamentary debates, the encounters of knights and warriors, essays on criticism and oratory, and all the other prosing dissertations with which so many of our school-collections are occupied.

Besides the questions referring to the descriptions contained in the lessons, a variety of miscellaneous questions, in reference to the common appearances of nature, and the different branches of popular science, might occasionally be proposed to the pupils to excite their curiosity, and exercise their reasoning powers. For example

How many miles should we require to travel before we could go quite round the world? What proofs can you give that the earth is round like a globe? Is there more land or water on the surface of the earth? What is meant by the atmosphere? Has the air any weight? By what experiments can you prove that the air presses upon our bodies, and upon all parts of the earth? How do you prove that air exists, since it cannot be What is the appearance of the sky during a thunder-storm? Whether is the lightning seen before or after a peal of thunder? By what means could you measure the distance between the earth and a thundercloud What effects does lightning sometimes produce? -How many

seen?

senses has man? Which is the organ of vision? What part of the eye lets in the light? Is the opening which lets in the light always of the same size? What knowledge do we derive by means of the sense of seeing? Have all animals the same number of eyes? What is peculiar in the eyes of flies and other insects ?-What are some of the different kinds of animals that live in the air, the waters, and the earth? What is the difference between a beast, a bird, and a fish? between a reptile and an insect? &c. Is a lobster a beast, a reptile, or a fish? What are the different parts of a plant? What part of a plant is the stem or trunk? What enables plants to stand upright, although they are tossed with the wind? Do all plants grow upright? What plants are useful for food? for building? for clothing? &c. What parts of our clothing are made from plants? Could we have clothing from animals, if no plants existed? What would be the appearance of fields and mountains, if there were no plants?-What are the tides? How often do they ebb and flow in the course of a day? At what periods of the moon are the tides highest? Does the sun appear round? Does the moon always appear round? What other phases or shapes does she assume? At what period of the day or night does the moon rise when she appears with a round full face? In what direction does she appear after sunset, when she assumes the form of a slender crescent ?--If you take a wine-glass, fill it with water, and press a piece of paper upon the mouth of it, and then turn it upside-down, will the water run out of the glass? If you take a glass tube, and fill it with water, and press your thumb hard upon the top of it, what is the reason that the water will not run out at the bottom of the tube, although it is open? When a boy's sucker is moistened with water, and pressed upon a smooth stone, what is the reason why it is able to lift up a stone of a pretty large size? Would the sucker produce the effect if it were not moistened with water?

Many thousands of queries of this description might be proposed to the young, which, if judiciously selected, explained, and illustrated, could not fail of gratifying their curiosity, and of im parting the elements of useful knowledge, and, above all, of exciting a spirit of observation, of fixing the attention, and of promoting a habit of reasoning on the various objects and operations they perceive around them. An hour or more, during two or three days in the week, might be profitably spent in such exercises, which should always be accompanied with familiar and minute explanations, and, where the subject admits of it, with amusing and illustrative experiments.*

Another occasional exercise might consist in exhibiting to a class a variety of objects, both natural and artificial,—such as, the model of a ship, a pair of bellows, a mineral substance, a shrub, a flower, a leaf, a bird, an insect, or any other objectand causing the pupils to describe the parts or qualities of the

A considerable variety of such questions as those to which I allude, will be found in an excellent little work, by Mr. Jacob Abbot, Principal of Mount Vernon School, entitled, The Little Philosopher."

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