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droughts so long and severe? and why is Palestine so subject to violent tempests, hurricanes, thunder storms, and hail storms? For the benefit of such of our readers as have not made the science of Meteorology a special study, we will preface our explanation with a few of its leading principles. We remark, then,

1. That as we ascend into the atmosphere, it grows colder and colder, about one degree for every three hundred feet, until we reach a region of continual frost, called the Region of Perpetual Congelation. This is Nature's grand laboratory of storms. Mountains often rise into this region, and are cov ered with perpetual snow. These become vast storehouses of cold during summer, exerting a chilling influence on the winds that meet them or blow over them.

2. That the great movements of the atmosphere, produc ing winds, are due chiefly to the agency of heat; inequality of temperature, disturbing the atmospheric equilibrium, being regarded as the general cause of winds. But winds cannot blow from one quarter towards another continually, without having their place supplied by air flowing in from some other quarter. It is commonly the case that a constant wind blowing in one direction, has above it a counter-current returning in the opposite direction. As the land is heated in summer and cooled in winter more easily than the ocean, movements of the atmosphere are thus occasioned by the reciprocal action of land and water, especially between continents and neighboring oceans. Great deserts, also, like those of Africa or Arabia, by the excessive rarefaction produced by the sun, determine the course of winds towards them. Thus on the coast of Guinea, the trade winds are diverted from their tendency towards the equator, by the influence of the great desert of Sahara in the interior of Africa.

3. That water is raised into the atmosphere, in the form of invisible elastic vapor, solely by the agency of heat. There is a certain fixed quantity of vapor which the air will contain, and no more; and this quantity depends on the temperature. The amount increases rapidly as the air grows warmer, doubling for every 25° of heat, so that air of 75° can hold twice as much

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watery vapor as air of 50°, and air of 100° twice as much as as air of 75°. But air seldom contains all it is capable of holding. It may not have half or a quarter as much; and when it thus contains much less vapor than is due to its temperature, it has great avidity for more, and when the deficiency is great, it exhibits the quality of extreme dryness. This is apt to be the case especially with hot winds. Having little watery vapor compared with what they are capable of containing, their avidity for water is extreme, and they instantly imbibe it from everything with which they come in contact. Winds that circulate over the land are usually dry; those circulating over the ocean are humid, and frequently saturated with moisture.

4. That watery vapor is deposited from the atmosphere, or condensed into the form of water solely by cooling. The temperature to which it must be reduced in order that the vapor may begin to be condensed, is called the dew point. If the air be very moist, then cooling it a few degrees will reach the dew point; but if the air is very dry, it must be cooled many degrees before reaching it. This cooling down to the dew point or below it, may take place under various circumstances. If air meets with a surface so much colder than itself as to reduce its temperature to the dew point, it deposits moisture on that surface in the form of dew, as is seen on the surface of a tumbler of cold water, especially before a thunder shower; or as seen on the ground itself when during the night the ground has become, as is usual on clear nights, some degrees colder than the air above it. If, however, the vapor condenses not on a cold surface, but in the atmosphere itself, near the earth, the water appears in the form of fog or mist, which may be produced in either of two ways,-by vapor rising from the ground and meeting with a cold stratum of air, or by a cold wind flowing in laterally. The same processes taking place in the upper regions produce clouds. If the reduction of temperature be much below the dew point, a greater quantity of water will be precipitated than is sufficient merely to form clouds, the particles of water will coalesce into drops, and will fall in rain. If, however, the temperature of the air be at or below the freezing point, the drops will crystallize and form

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know. We will suppose an extreme case,—that a body of hot and humid air is suddenly hurled aloft by a whirlwind far within the region of perpetual congelation, where the cold is very interse. Half or three-fourths of all the watery vapor will be suddenly precipitated, forming hail, and the small hail stones thus formed may be increased in size by being buoyed up for a long t'me, by the mechanical force of the wind, and congeal upon these successive portions of vapor, until they attain an enormous size. When watery vapor is condensed into water, electricity is evolved. If the air be hot and humid, and vapor be suddenly condensed in great quantity, the electricity evolved is abundant, accumulates, and manifests its presence by thunder and lightning, as is the case in our sunimer showers, and especially in hail storms.

We regard, then, all these meteorological phenomena-dew, fog, clouds, rain, snow, hail, and thunder and lightning, as de. pending on one and the same simple principle, acting in different degrees of intensity.

In the light of these principles, let us now look at Palestine. We compared it in extent to the state of Vermont. Why is its meteorology so much more diversified and remarkable! Vermont is surrounded on all sides by countries like itself. But how different is the case with Palestine! We have on the north the snow-clad mountains of Lebanon and Anti-Lebanon, their highest peaks covered with perpetual snow; and beyond,

" within three hundred miles, are the lofty ranges of Mount Taurus. On the east, we have the arid desert plains of Syria and Mesopotamia; on the south the hot, sandy deserts of Arabia; on the west the ocean-like expanse of the Mediterranean. Let us reflect what must be the respective qualities of the winds blowing over the snowy mountains of the north, or the arid plains of the east, or the hot sandy deserts of the south, or the temperate waters of the west. The occasional cold blasts of Palestine we see at once are borrowed from the snow-clad mountains of the north. The extraordinary heat of the valley of the Jordan and the plain of Esdraelon, are derived not merely from the low latitudes which expose them to a hot summer's sun, but to several aggravating causes. Esdraelon is a

level plain nearly surrouuded by the mountains of Carmel, Tabor, and Gilboa, from which the solar rays are reflected upon it. The valley of the Jordan owes its excessive heat to similar and more direct reflections from the bare and steep mountains that wall it on the east and west. Moreover, as elevation above the general level of the earth brings us to a cooler inedium, so prolonging the atmospheric column into this deep abyss brings us to a hotter medium. The plain of Esdraelon from west to east, and the Jordan valley from south to north, each presents a gorge through which the dreaded sirocco flows. The sirocco, a whirlwind formed on the burning deserts south and east, occasionally flies northward, spreading its deadly wings over every part of the Holy Land.

The maritime coast is tempered by the land and sea breezes; the central portion embracing Jerusalem, by its elevation so far above the general level of the earth.

The heavy dews arise from the great difference of temperature between the days and nights. In those cloudless summer skies the ground at night rapidly radiates its heat into space, and presents to the air that circulates over it, a

, cold surface most favorable for the deposition of dew.

The constancy of the northwesterly winds at Jerusalem, and all the interior of Palestine, is probably due to their tendency towards the great deserts on the south and east. During summer these winds, coming from the Mediterranean, grow warmer and of course drier as they blow over the land; but in winter they meet a colder medium, and occasionally, as we learn by recorded observations, they meet the cold blasts from the north, and impetuous showers of rain descend. The same causes acting in extraordinary intensity will go beyond the common course of nature, and result in thunder and lightning and hail.

While reflecting with wonder at the unparalleled diversity presented by the geography and climate of Palestine, we have often been struck with the analogy which exists between its physical features and its political and religious history. If it has a greater variety of soil and climate than any other part of the globe, within the same compass, so it surpasses all other

countries in the succession of great events of which it has been the theater. In no other land, not in Egypt itself, do we look so far into the depths of antiquity. Those mystic ruins which lie scattered over every hill top, carry us back almost to the days of the flood. It was the common battle ground of the most ancient nations, where the Assyrian hosts, pouring through the defile between the mountain ridges of Lebanon and Anti-Lebanon, met the vast armies of Egypt from the south. On the rocks that overhang one of the crystal streams of Mount Lebanon, we read inscriptions which are the chroniclers of ages; where are seen together the cunei-forin characters of Sennacherib, the hieroglyphics of Rameses the Great, and the Latin characters of Marcus Antoninus. It is the land of the patriarchs, and the center of the true religion in a world of idol, aters. It is the land of sacred minstrels and holy prophetsit is the land of the REDEEMER !—the land where the Canaanite, the Assyrian, the Persian, the Macedonian, the Saracen, the Roman, the Turk, have successively borne their iron rule—the land of apostles and martyrs--the land of the crusades—the land of the holy city, the city of the Great King, towards which the Jew, an outcast in every nation, still looks up with longing eyethe type of the heavenly Jerusalem, whither all “the redeemed of the Lord shall come with singing unto Zion; and everlasting joy shall be upon their head; they shall obtain gladness and joy; and sorrow and mourning shall flee away."

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