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living forms. To Eastern Asia, where philosophy has been accustomed to the abstract idea of force, the pleasures we derive from this contemplation are denied, the cheerless doctrine of Buddhism likening the life of man to the burning of a lamp, and death to its extinction. Perceiving in the mutation of things, as seen in the narrow range of human vision, a suggestion of the variations and distribution of power throughout nature, it rises to a grand, and, it must be added, an awful conception of the universe.

But Europe, and also the Mohammedan nations of Asia, have not received with approbation that view. To them there is an individualized impersonation of the The human soul, and an expectation of its life hereafter. soul. The animal fabric is only an instrument for its use. The eye is the window through which that mysterious principle perceives: through the ear are brought to its attention articulate sounds and harmonies; by the other organs the sensible qualities of bodies are made known. From the silent chambers and winding labyrinths of the brain the veiled enchantress looks forth on the outer world, and holds the subservient body in an irresistible spell.

of the world.

This difference between the Oriental and European ideas respecting the nature of man reappears in their Extension of ideas respecting the nature of the world. The these views one sees in it only a gigantic engine, in which to the nature stars and orbs are diffusing power and running through predestined mutations. The other, with better philosophy and a higher science, asserts a personal God, who considers and orders events in a vast panorama before him.

CHAPTER XI.

THE EUROPEAN AGE OF REASON-(Continued)

THE UNION OF SCIENCE AND INDUSTRY.

European Progress in the Acquisition of exact Knowledge-Its Resem blance to that of Greece.

Discoveries respecting the Air-Its mechanical and chemical Properties -Its Relation to Animals and Plants.-The Winds.-Meteorology.Sounds.-Acoustic Phenomena

Discoveries respecting the Ocean - Fhysical and chemical Phenomena.-Tides and Currents.-Clouds-Decomposition of Water. Discoveries respecting other material Substances.-Progress of Chemistry. Discoveries respecting Electricity. Magnetism, Light, Heat

Mechanical Philosophy and Inventions-Physical Instruments.-The Result illustrated by the Cotton Manufacture-Steam-engine-Bleaching-Canals-Railways.-Improvements in the Construction of Machinery.-Social Changes produced.-Its Effect on intellectual Activity. The scientific Contributions of various Nations, and especially of Italy. THE Age of Reason in Europe presents all the peculiarities of the Age of Reason in Greece. There are modern representatives of King Ptolemy Philadelphus among his furnaces and crucibles; of Hipparchus cataloguing the stars; of Aristyllus and Timochares, with their stone quadrants and armils, ascertaining the planetary motions; of Eratosthenes measuring the size of the earth; of Herophilus dissecting the human body; of Archimedes settling the laws of mechanics and hydrostatics; of Manetho collating the annals of the old dynasties of Egypt; of Euclid and Apollonius improving mathematics. There Analogies be- are botanical gardens and zoological menageries tween the Age like those of Alexandria, and expeditions to the Europe and in sources of the Nile. The direction of thought is Greece. the same; but the progress is on a greater scale, and illustrated by more imposing results. The exploring

of Reason in

voyages to Madagascar are replaced by circumnavigations of the world; the revolving steam-engine of Hero by the double-acting engine of Watt; the great galley of Ptolemy, with its many banks of rowers, by the ocean steam-ship; the solitary watch-fire on the Pharos by a thousand lighthouses, with their fixed and revolving lights; the courier on his Arab horse by the locomotive and electric telegraph; the scriptorium in the Serapion, with its shelves of papyrus, by countless printing-presses; the "Almagest" of Ptolemy by the "Principia" of Newton; and the Museum itself by English, French, Italian, German, Dutch, and Russian philosophical societies, universities, colleges, and other institutions of learning.

the acquisi

So grand is the scale on which this cultivation of science has been resumed, so many are those European engaged in it, so rapid is the advance, and so progress in great are the material advantages, that there is tion of knowno difficulty in appreciating the age of which it ledge. is the characteristic. The most superficial outline enables us to recognize at once its resemblance to that period of Greek life to which I have referred. To bring its features into relief, I shall devote a few pages to a cursory review of the progress of some of the departments of science, selecting for the purpose topics of general interest.

First, then, as respects the atmosphere, and the phenomena connected with it.

From observations on the twilight, the elasticity of aerial bodies, and the condensing action of cold, The atmothe conclusion previously arrived at by Alhazen sphere. was established, that the atmosphere does not extend unlimitedly into space. Its height is considered to be about forty-five miles. From its compressibility, the greater part of it is within a much smaller limit; were it of uniform density, it would not extend more than 29,000 feet. Hence, comparing it with the dimensions of the earth, it is an insignificant aerial shell, in thickness not the eightieth part of the distance to the earth's centre, and its immensity altogether an illusion. It bears about the same proportion to the earth that the down upon a peach bears to the peach itself.

A foundation for the mechanical theory of the atmo

sphere was laid as soon as just ideas respecting liquid pressures, as formerly taught by Archimedes, were restored, the conditions of vertical and oblique pressures investigated, the demonstration of equality of pressures in all directions given, and the proof furnished that the force of a liquid on the bottom of a vessel may be very much greater than its weight.

Such of these conclusions as were applicable were soon Its mechani- transferred to the case of aerial bodies. The cal relations. weight of the atmosphere was demonstrated, its pressure illustrated and measured; then came the dispute about the action of pumps, and the overthrow of the Aristotelian doctrine of the horror of a vacuum. Coincidently occurred the invention of the barometer, and the proof of its true theory, both on a steeple in Paris and on a mountain in Auvergne. The invention of the air-pump, and its beautiful illustrations of the properties of the atmosphere, extended in a singular manner the taste for natural philosophy.

The mechanics of the air was soon followed by its cheIts chemical mistry. From remote ages it had been numrelations. bered among the elements, though considered liable to vitiation or foulness. The great discovery of oxygen gas placed its chemical relations in their proper position. One after another, other gases, both simple and compound, were discovered. Then it was recognized that the atmosphere is the common receptacle for all gases and vapours, and the problem whether, in the course of ages, it has ever undergone change in its constitution arose for solution. The negative determination of that problem, so far as a few thousand years are concerned, was necessarily followed by a recognition of the antagonism of animals and plants, and their mutually balancing each other, the latter accomplishing their duty under the influence of the sun, though he is a hundred millions of miles distant. From this it appeared that it is not by incessant interventions that the sum total of animal life is adjusted to that of vegetable, but that, in this respect, the system of government of the world is by the operation of natural causes and law, a conclusion the more imposing since it contemplates all living things, and

The antagonism of

animals and

plants.

includes even man himself. The detail of these investigations proved that the organic substance of plants is condensed from the inorganic air to which that of all animals returns, the particles running in ever-repeating cycles, now in the air, now in plants, now in animals, now in the air again, the impulse of movement being in the sun, from whom has come the force incorporated in plant tissues, and eventually disengaged in our fires, shining in our flames, oppressing us in fevers, and surprising us in blushes.

Organic disturbances by respiration and the growth of plants being in the lowest stratum of the air, its uniformity of composition would be impossible The winds; were it not for the agency of the winds and the their origin diffusion of gases, which it was found would

take place under any pressure. The winds were at length properly referred to the influence of the sun, whose heat warms the air, causing it to ascend, while other portions flow in below. The explanation of land and sea breezes was given, and in the trade-wind was found a proof of the rotation of the earth. At a later period followed the explanation of monsoons in the alternate heating and cooling of Asia and Africa on opposite sides of the line, and of tornadoes, which are disks of air rotating round a translated axis with a diameter of one hundred or one hundred and fifty miles, the axis moving in a curvilinear track with a progressive advance of twenty or twenty-five miles an hour, and the motions being in opposite directions in opposite hemispheres of the globe.

The equatorial calms and trade-winds accounted for on physical principles, it was admitted that the winds of high latitudes, proverbially uncertain as they are, depend in like manner on physical causes.

With these palpable movements there are others of a less obvious kind. Through the air, and by reason of motions in it, sounds are transmitted to us.

The Alexandrian mathematicians made sound a favourite study. Modern acoustics arose from the recognition that there is nothing issuing from the sounding of sounds; body, but that its parts are vibrating and their velocity. affecting the medium between it and the ear. Not only

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