than does the water. It contracts, and in the higher levels flows back from the water.

The average hourly pressure for a considerable period will show the barometer rises from 4 A.M. to 10 A.M.; then falls to 4 P.M., and rises to a second daily maximum at 10 P.M.; when it slowly falls to a secondary minimum at 4 A.M. These variations are greatest at the equator, diminishing with latitude until they are hardly distinguishable at the poles.

General Circulation. In the tropics the winds blow almost continuously from the northeast in the northern hemisphere and from the southeast in the southern hemisphere, with irregular winds, mostly from the west in extratropical regions. The explanation of the trade winds is that the heat of the sun raises the temperature and expands the air most where its rays fall nearly perpendicularly. This causes the air to ascend in the region of the equator and to flow in along the surface from either side. Since, however, air moving from higher to lower latitudes passes successively over parallels having greater easterly motion than its own, or rather greater than the parallel whence it started, it would, on account of its momentum, fall behind the diurnal motion of the earth and be deflected more and more to the west. Over the warmest belt it would rise. In rising it would cool by expansion, so that in flowing away from the equator, as it must do to make room for the air continually flowing in at the surface, its tendency would be to gradually fall, reaching the surface in temperate latitudes and contributing to create the belt of high pressure existing at latitude 35° each side of the equator.

The air aloft in going from low to high latitudes passes successively over parallels of latitude having less and less easterly motion, so that it runs ahead of the diurnal rotation of the earth or is deflected more and more to the cast, giving us the prevailing westerly winds of the temperate zones when this air comes to earth.

From the isothermal level downward to the surface, between latitudes 30° and the poles, there are cyclonic circulations, central at the poles. The centrifugal force of these winds, because they run ahead of the earth, is greater than it would be if they ran with it, and consequently the air of high latitudes, as it encircles the globe, tends to pile up over latitudes farther south.

Local Circulation.-As previously indicated, the permanent circulations are due to equatorial heating and polar cooling and to the great subpermanent high pressure and low pressure systems created by the different heating effects of continents and oceans. Recently these systems have been called Great Centres of Action. They are built up and disintegrated and change their geographical positions slowly. While they do not have a velocity of translation, like the ordinary cyclones and anti-cyclones that move across continents and oceans and cause the changes of weather that occur from day to day, they do profoundly influence the intensity of storms and the path along which they may move. They, therefore, determine, in a general way, whether the character of the weather for weeks at a time shall be wetter or drier, colder or warmer, than the seasonal average.

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Cyclones. The cyclone, or low pressure, is a system of spirally inflowing winds which ascend in the region of the centre, cool by expansion with gain in altitude and usually cause precipitation in the form of rain or snow. At or below the heights of the wispy cirrus clouds the air flows outward, and at some more or less remote place moves downward in the form of an anti-cyclone. Storms move eastward in the middle latitudes and westward in the tropics, and rotate counter-clockwise in the northern hemisphere and in the opposite direction in the southern hemisphere. While the velocity of gyration may be anywhere from zero to 100 miles per hour, depending upon the steepness of the barometric gradient toward the centre, the velocity of translation of the whole whirling mass usually varies from 20 miles per hour in summer to 40 miles in winter.

Anti-cyclone. In the anti-cyclone all the movements of the cyclone are reversed except the direction of translation. The air flows downward near the centre and spirally outward along the surface of the earth. It usually is accompanied by clear, cool and settled weather, and this notwithstanding the fact that the air heats by compression as it descends, which apparent inconsistency will be explained in the paragraph on Cold Waves.

Origin of Storms.-Any flowing together of the air between two anti-cyclones must produce a cyclone, and it has been shown that the unequal heating effects of land and water surfaces may be sufficient to initiate cyclonic and anti-cyclonic action.

A hypothesis to account for the beginning of storms that is attracting the attention of meteorologists, assumes that the earth, at times, passes through shafts of extra solar heat, which expand the air at the equator more than they do at higher latitudes, causing the atmosphere at the equator to bulge up until masses at high levels gravitate toward the poles. These masses cool by expansion and by radiation, gain in specific gravity and sink to the earth in the middle latitudes or the north part of the temperate zone. As they come down they rotate in an anti-cyclonic manner and constitute cold waves. Each descending mass forces the ascent of cyclonic whirls or storms on either side. The storms thus formed may move eastward for great distances, crossing continents and oceans before being disintegrated. According to theory these extra heat shafts from the sun may persist for months and return to affect our weather with each 25-day rotation of the luminary. An allowance of 18 days is made for the air to perform the overhead circulation from the equator after each heat impulse before the cold wave appears on our western border. According to this hypothesis these cold masses should settle over land in winter and over oceans in summer, which agrees with observed fact.

Abbot's researches have shown much of the varied character of solar radiation. With a continuation of his work and of that of Kimball, of the Weather Bureau, whose investigations were begun and continued for many years under the direction of the author, the time may come when the general character of seasons may be foretold.

Temperatures of Cyclones and Anticyclones. According to Ferrel and other early

students temperature is supposed to be arranged systematically about the centres of cyclones and anti-cyclones. We now know that such is not the case, that the cyclone as a whole is not a warm area, nor is the anti-cyclone a cold area, but that the rising temperature occurs on the western side of the high area and on the eastern side of the low area, and that the falling temperature is on the western side of the low area and on the eastern side of the high area.

Hurricanes. The hurricane of the West Indies is the same as the typhoon of the Philippines and the China coast. The ordinary cyclonic storm that crosses the United States is about 1,000 miles in diameter. The hurricane is a cyclone usually of only about 100 to 300 miles in diameter, but with a gyratory velocity far in excess of the storms of the temperate latitudes. It occurs in the tropics, moves westward and northward at the rate of only 7 to 12 miles per hour, while the air inside of the storm may be whirling at the rate of over 100 miles. At latitude 26° its path recurves in the form of a parabola, and the storm passes to the northeast. They occur mainly in the four months July to October.

Tornadoes. The tornado also is cyclonic in its movements, but instead of being 1,000 miles in diameter like the continental cyclone, or 100 miles like the tropical hurricane, it usually has a diameter of gyration of only about 100 to 300 yards, and its speed of rotation is so terrific that no instruments have ever held together long enough to measure its velocity, which must equal or exceed that of a rifle bullet, as the writer has seen wheat straws that were shot by the wind of a tornado one-half inch into the tough body of an oak tree, and a two by four pine scantling driven through fiveeighths of an inch of solid iron. As a rule they occur in the spring of the year, in the southeast quadrant of a cyclone, when the temperature and humidity are high. Their direction nearly always is toward the northeast. They occur with the greatest frequency in the States bordering on the Mississippi River.

Thunderstorms.- The thunder storm turns about a horizontal axis instead of a vertical one, as in the case of the tornado. On land thunderstorms occur most frequently at specified hours of the day or night, such as 3 to 5 in the afternoon or 9 to 10 in the evening, and sometimes even at 2 or 3 in the morning, but no such periods are observed over the ocean. They occur at any hour of the day or night with equal frequency. In regard to the electrical phenomena of the atmosphere it is not safe to hazard definite statements, but possibly auroras are due to earth-captured solar electrons, while the lightning of a thunderstorm owes its origin, chiefly at least, to the electrical separation produced by the action of wind on raindrops.

Cold Waves. The area and intensity of cold waves depends upon the size of the continents and their distance from the equator. The interiors of North America and of Siberia experience more severe cold than occurs at either pole. Departures from the normal temperature of a time and place are due to the dynamic heating and cooling of the air through its upward and downward motions below the six or seven-mile level. Air heats by com

pression at the rate of about 1° for each 200 feet of descent in the anti-cyclone, but this heating induces clearness through the evaporation of clouds and allows a rapid loss of heat by radiation. And then the temperature of the air before it starts on its downward journey is so low that notwithstanding the heat of compression, it may be extremely cold when it reaches the earth. However, it is difficult to formulate any hypothesis that will fully account for the cold of the east side of the anticyclone being so much greater than that of the west side, or for the heat of the east side of the cyclone being so in excess of that of the west side.

Warm Waves. In summer there come periods of stagnation in the drift of the highs and the lows. At such times if a high sluggishly rests over the south Atlantic Ocean between Bermuda and the coast of the United States and a low over the northern Rocky Mountain region, there will result what is popularly known as a warm wave, for the air will slowly and steadily flow from the southcast, where the pressure is greater, toward the northwest, where the pressure is less, and, receiving constant accretions of heat from the hot, radiating surface of the earth, finally become abnormally heated. This superheated condition continues until the high over the ocean dies out or drifts away. Consult Davis 'Elementary Meteorology) (Boston 1894); Ferrel, William, Treatise on the Winds' (New York 1893); Flammarion, Thunder and Lightning (Boston 1906); Hann, 'Lehrbuch der Meteorologie (3d ed., Leipzig 1914); Milham, 'Meteorology' (New York 1912); Moore, Descriptive Meteorology' (ib., 1910); Ward Practical Exercises in Elementary Meteorology' (Boston 1899).

WILLIS LUTHER MOORE, Professor of Meteorology, George Washington University.

METEOROLOGY, Marine, differs from that of land areas chiefly from the fact that the rays of the sun penetrate more deeply into the ocean substance than into the land and that the diffusion of this heat through the water body is practically uniform. The ocean thus becomes a vast storage reservoir of heat which is but slowly returned to the atmosphere. The effect upon the ocean climate is to render it more equable. An example of this is seen in the climate of the British Isles, Ireland particularly, where the prevalent west winds coming from the great ocean area temper the climate to a remarkable degree. It is a fact notable in this connection that in the approach of winter in the northern hemisphere, when the frost line on the land areas has reached as far south as the parallel of 38° N., on the ocean areas it is still at 65° N. Ocean storms are generally more severe than land storms, but exhibit a close approximation to theoretical form and their progress can be much more accurately foretold. Consult McAdie, A. G., 'Principles of Aerography (Chicago 1917); Moore, Sir J. W., Meterology Practical and Applied) (London 1910).

METEORS. See SHOOTING STARS.
METH. See MEAD.

METHANE, CH,, also known in the impure state as Marsh Gas, or Firedamp, is found in large quantities in the gases evolved from petroleum wells, oil springs and mud volcanoes. It is present in stagnant pools (hence the name marsh gas) and in certain localities where organic matter is allowed to decay in a limited supply of air. The firedamp of coal mines is methane mixed with a small percentage of carbon dioxide, nitrogen and oxygen. Enormous quantities of methane are present in the burning gases that constitute the "Holy Fire" at Baku in the neighborhood of the Caspian Sea. Methane is formed in the fermentation of compounds like cellulose, milk sugar or calcium butyrate, in the thermal decomposition of alcohol, ethane, ethylene or acetylene and in the dry distillation of vegetable matter. Illuminating gas, produced by the destructive distillation of coal, may contain as much as 40 per cent of methane by volume.

The compound may be prepared in a fairly pure state, (1) by treating commercial aluminum carbide with water; (2) by the interaction of hydrogen and an oxide of carbon at 250° C., in the presence of finely-divided catalyzers like cobalt, nickel or iron; (3) by heating a mixture of fused sodium acetate and dry soda-lime; (4) by the interaction of carbon bisulphide, metallic copper and hydrogen sulphide at an elevated temperature; (5) by maintaining charcoal from sugar in a stream of pure, dry hydrogen at 1.150° C. Chemically pure methane has been prepared by the reduction of methyl iodide. In this process the iodine is mixed with equal volume of alcohol and treated with the "zinc-copper" couple.

Methane is a colorless inodorous gas with a density 0.559 (air=1). It burns with a faintly luminous flame and with the evolution of much heat. Mixed with air or oxygen in certain proportions and then ignited it explodes violently, one volume of methane forming with 9.5 volumes of air an extremely explosive mixture. On account of its low boiling point methane was for a long time known as one of the permanent gases. It was liquefied by Cailletet in 1877. The liquid is colorless, boils at - 164° C. and solidifies at 185.5° C. when the pressure is diminished to 80 millimeters.

-

Methane is a saturated compound and is extremely stable. Reagents like fuming nitric acid, strong sulphuric acid or phosphoric anhydride have practically no action upon it even at elevated temperatures. In the presence of chlorine, bromine or fluorine, methane undergoes a chemical change by substitution, i.e., by the replacement of one or more hydrogen atoms by equivalent atoms of the halogen. Long contact with chlorine, for example, even in diffused daylight and at ordinary temperatures, will convert methane into CH C1 (methyl chloride), CH2Cl2 (methylene chloride), CHC1, (chloroform) and CCl (carbon tetrachloride), a molecule of hydrochloric acid being evolved with the introduction of each atom of halogen. At temperatures not lower than 1.300° C. methane has been completely decomposed into carbon and hydrogen. With a mixture of nitrogen and hydrogen in the electric arc it has been successfully converted into hydrocyanic acid. Patents have also been taken for the oxidation of methane (under the catalytic action of tan bark) into formic acid,

VOL. 1846

methyl alcohol and formaldehyde. IN MINES AND COAL.

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Sce GASES

V. S. BABASINIAN,

Professor of Chemistry, Lehigh University. METHODIST BOOK CONCERN. See METHODIST EPISCOPAL CHURCH.

METHODIST CHURCH (SOUTH). See METHODIST CHURCHES OF THE WORLD.

METHODIST CHURCH UNION. The Methodist Episcopal Church was divided in 1844 by the subject of slavery. This led to the formation of the Methodist Episcopal Church, South. Beginning with a conference at Cape May, in 1876, several attempts have been made looking toward union. The General Conference of the Methodist Episcopal Church, South, appointed a commission in 1914. The next General Conference of the Methodist Episcopal Church which met at Saratoga, N. Y., in 1916, also appointed a commission. The commissions have held several meetings together but have not yet arrived at conclusions. The bond between the two denominations is very close. They have already united in some of their mission work, especially in education and publication. Many leaders of the Methodist Protestant Church look forward to the time when their body will also be included in the union. The combined membership would be in excess of 6,000,000. In the meantime the three largest groups of Colored Methodists including the African Methodist Episcopal Church, the African Methodist Episcopal Zion Church and the Colored Methodist Episcopal Church, have taken the preliminary steps looking toward union in 1924. They hope that the negro members of the Methodist Episcopal Church will unite with them. The total combined membership of the four groups would be more than 3,000,000.

METHODIST CHURCHES OF THE WORLD. A group of 25 organized bodies which represent an evangelical type of the Christian religion, and which, rising under the Wesleys in England, in the 18th century, has been spread to all countries and has become one of the great Christian Communions.

History of English Methodism.- The rise of Methodism was on this wise. John and Charles Wesley, clergymen of the Church of England, as their father was before them, formed, 1729, at Oxford University, with others, a club for the promotion of personal religion. Being very earnest young men, they proceeded to draw a series of rules of conduct, which were somewhat strict for the times, and observed so carefully that they were called in derision, "Methodists," and their little company was termed the "Holy Club." They prayed much, read devotional books and visited the sick and unfortunate. The age was one of laxness in religious observance and of indulgence in gambling, drinking and other vices and immoralities, which invaded church circles. This tended to deepen the earnestness and enthusiasm of the young reformers and a revival was the natural outcome, the sweep and influence of which no one of them could have imagined. Three men of remarkable power were at the head of the movement, John Wesley (born in 1703), preacher, leader, organizer, author, indefatigable worker; Charles Wesley

(born in 1707), pupit orator, unequaled hymn writer; George Whitefield (born in 1714), evangelist, whose fiery zeal and persuasive eloquence won tens of thousands on both sides of the ocean. All of them great preachers, John was pre-eminently the organizer. His religious experience passed through several stages, the last of which was in 1738, when at a Moravian meeting in London, he "felt his heart strangely warmed." The next year he began to organize converts into societies, which was the actual epoch of Methodism. Opposition in the Church of England, which closed its churches to him, compelled him to resort to open-air preaching which multiplied his hearers and made the movement a people's movement. The preaching was clear, direct, simple, setting forth the doctrine of a free, full, present salvation from sin by faith, and presenting religion of the heart rather than of the head. The Wesleys never severed their relation with the Church of England, nor abandoned its doctrinal and ecclesiastical systems. Methodism in England was a movement within the Church, to which the societies looked for the sacraments until after the death of the founder.

The Methodist system was a gradual development out of the conditions which forced Wesley to take steps contrary to his High Church ideas. Consecrated places being shut to Methodist meetings, he had to build chapels and hold services in schools, private houses and barns, and in the open air; ministers being too few to do the preaching, he called to his aid laymen; societies increased so rapidly that it was necessary to plan for their care, hence the annual conference; changes in appointments being necessary, the itinerancy was developed to regulate them. Other distinctive features of Methodism, the class meeting for testimony and prayer; bookrooms for the publishing and sale of a growing body of denominational literature, and the conference study for the training of preachers not college bred, were likewise in answer to the demand of a rapidly expanding propaganda.

British Methodism did not, after the death of John Wesley, escape the fate of division. Indeed, radical doctrinal differences developed between him and Whitefield, and a separation took place, the latter being a pronounced Calvinist and the former a strong Arminian. One cause or another brought a number of separations, with 9 or 10 different branches. By the process of union several of these have disappeared and there are now five distinct bodies, not including the Welsh Calvinistic Methodist Church which affiliates with the Presbyterian churches.

1. Wesleyan Methodist Church.- John Wesley dominated in absolute fashion the organization he had treated, until the success of the American Revolution compelled recognition of the independence of the societies in the United States and in England, as long as he lived. He held both property and patronage; but in anticipation of his death (1791), he prepared a "Deed of Declaration" which constituted 100 preachers, selected by himself, a Legal Conference to hold the Church property and provide for the annual appointment of the preachers. Thus was distributed the large powers which he had held in his own hands

and which he was apparently unwilling to entrust to any individual as his successor.

The first Wesleyan Methodist Conference was held in 1744, when Wesley counseled with his preachers and a few clergymen who favored his work, and rules were adopted for the benefit of the societies and the preachers. Later on, separate conferences were held in Ireland, which Wesley had first visited in 1747, and in America, in 1773, whither two preachers had been sent in 1769. In 1770 there were upward of 29,000 members and probationers in the British societies, and at the time of Wesley's death, 71,568. This success had not been obtained without a great deal of hard labor, in which Wesley himself was the chief, continually traveling, preaching at all hours of the day and night, and enduring besides the natural discomforts of his journeys and exposures, obloquy, abuse and even mob and individual violence.

After his death the Conference was at odds on the question of the administration of the sacraments. At its session in 1792, it prohibited them, removing the prohibition in 1793 and subsequently providing for them, and later still for the ordination of ministers. In the 19th century, Home and Foreign Missionary societies were formed and other denominational enterprises instituted. There are two colleges, Wesley, at Sheffield, and Queen's, at Taunton, and a theological college in four places. Lay members were admitted to the Conference in 1878. Beside the annual Conference in England there are conferences in Ireland, France and South Africa. The Church has in Great Britain (1917) nearly 492,000 members and probationers, and in other conferences and its foreign missions, 361,398; in all, 853,398. Methodism is intensely missionary in its spirit, by which it has been carried to the ends of the earth. Wesley's first missionaries were sent to the American colonies and next to the West Indies, 1786. Missions in Africa and Ceylon were begun in 1811 and 1813, respectively. Now the missions of the Methodist bodies of Great Britain, Ireland and Australasia are in all the continents, some of the earlier and most notable successes being in Fiji and other South Sea islands, from which savagery was banished long ago. various Methodist bodies reported to the Ecumenical Methodist Conference in 1911 an aggregate of $2,540,000 in income for foreign missions which are in the countries of Europe, Asia, Africa, South America and the West Indies.

The