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given only to the rich ore. The furnaces in which the poor ore is treated are thirteen feet high and three feet three inches in diameter. Each furnace is closed at the top by a hopper with two doors, the upper of which has a water-joint. Twelve charges are made each day, and care is taken to open the upper door as little as possible. The charge consists of two hundred-weight of ore, mixed with a quarter the quantity of charcoal. It is lowered into the furnace by opening the lower door, while the upper door is closed; and a fire is kept burning at the upper part of the furnace to prevent the escape of the gases. The mercurial vapors and gases of combustion are led by a chimney into condensing chambers. From 150 to 160 tons of ore are extracted at the Siele mines every month about 22 tons of metallic quicksilver; and this is packed in about 300 cans with screw stoppers.
Aluminum.—The only establishment at which aluminum is regularly manufactured is at Salindres, where about 2,400 kilometres are produced annually. The metal is prepared by melting the double chloride of aluminum and sodium with sodium and some cryolite as a flux. The new method of obtaining the metal from bauxite, proposed by Mr. Webster, does not promise to be as successful in cheapening its cost as its author hoped it would be. Mr. Webster has suggested a process of preparation of alumina, for the purpose of manufacturing aluminum, by heating alum with coal-pitch; subjecting the resultant mass, broken to pieces, to the action of hydrochloric acid, for the elimination of sulphureted hydrogen; adding 5 per cent. of charcoal-powder or lamp-black, with enough water to make a thick mass; drying the mass made up into balls, and heating the balls to a red heat for three hours under exposure to air and the vapor of water, for the conversion of sulphur and carbon into sulphur dioxide and carbon dioxide, and the removal of impurities. The dry residue, which consists of aluminum oxide and potassium sul
hate, is cooled and ground to a fine powder. #. powder is then treated with about seven times its weight of water and boiled for about an hour. The solution containing potassium sulphate is then run off and evaporated to dryness, and the alumina is washed out and dried. Mr. J. Morris, of Uddington, near Glasgow, claims to obtain aluminum by treating an intimate mixture of alumina and charcoal with carbon dioxide. For this purpose a solution of aluminum chloride is mixed with powdered wood, charcoal, and lamp-black, and then evaporated, until it forms a viscous mass, which is shaped into balls. During the evaporation hydrochloric acid is given off. The residue consists of alumina intimately mixed with charcoal. The balls are dried, and then heated with steam in appropriate vessels for the purpose of driving off all the chlorine, care being taken to keep the temperature so high that the steam is not condensed. The temperature is
then raised, so that in the dark the tubes are seen to be at a low red heat, and dry carbon dioxide is passed through. This is said to be reduced by the charcoal to carbon monoxide, which, as affirmed by Mr. Morris, reduces the alumina to aluminum, the metal appearing as a porous, spongy mass. Precious Metals.-Prof. Chandler Roberts, who is engaged in the study of metals at temperatures above their melting-points, has described some experiments on the mobility of gold and silver in melted lead. If a lump of a gold-lead alloy with 30 per cent. of gold, covered with lead, is heated in a crucible, the gold appears at the surface the very moment when perfect fusion has been attained. The diffusion also takes place rapidly if the gold alloy isput in a small crucible, and this is placed within another crucible containing lead. By melting in a cylinder, 200 millimetres high, a solid cylinder of lead with a small piece of the gold alloy fused to its bottom—or, better still, by o the gold at the top of one limb of a -shaped crucible, and withdrawing test portions from the top end of the other limb–Mr. Roberts arrived at the diffusion rate, 300 millimetres in five minutes for gold. Sir William Thomson has characterized this as a great discovery, remarking that the rate of diffusion of gold in lead appeared to be immensely greater than the rate of diffusion of liquids. The subject, he said, is one, in fact, of which we understand very little, but the property will probably prove of great value in metallurgy, where one example of it, the rapid mixture of spiegeleisen with iron, is well known. Messrs. Blas and Miest have discovered that if, in electrolysis, compressed ores are used as anode in a bath of an electrolyte containing the same metal as the metal of the ore, on the passage of the current the ore is decomposed, the sulphur, etc., being precipitated at the anode, while the metal collects at the cathode. When ores containing several metals are operated on, the precious metals, being most easily precipitated, are thrown down first in the metallic state at the cathode under the action of a moderate current. The final separation of these metals requires very little battery-power; for the mass of metal, when dissolved under the action of the current, generates sufficient heat for the ulterior separation of each metal. The products at the anode are extracted and purified by treatment with carbon bisulphide, and afterward by separate electrolysis. Alloys.-Mr. Alexander Dick has produced a new copper-zinc alloy, which he calls Deltametal, and which, it is claimed, exhibits characteristics as essentially superior to brass as those of bronze are to gun-metal. Its advantages are great strength and toughness, and a capacity for being rolled, forged, and drawn. It can be made as hard as mild steel, and when melted is very liquid and capable of producing sound castings of close, fine grain. The color can be varied from that of yellow brass to that of rich gun-metal. The surface takes a fine polish, and tarnishes less than brass. The metal when cast in sand has a breaking strain of from 21 to 22 tons per square inch. When rolled or forged hot into rods, the breaking strain is 43 tons per square inch ; and when drawn into wire of 22 B. W. G., it is of 67 tons per square inch. Messrs. Cockshott and Jowett, of Bradford, England, have produced an alloy of manganese with phosphorus and tin and copper which possesses superior qualities of tensile strength and durability. The phosphor-manganese-tin may be used in the same manner and in similar proportions as phosphor-tin, though it should be cast at a little higher temperature, but with more satisfactory results. It furnishes a very convenient form of the combination of manganese and phosphorus, which is valuable on account of the facility it affords the brassfounder, by adding a greater or less proportion of copper, etc., to produce bronze of a quality exactly suitable to the purpose for which it is required. The bronze is made in two qualities, both selling at the same price. The first quality is very tough, and suitable for purposes where the castings are required to withstand a great strain, having been tested successfully for a strain of 34,754 pounds per square inch. The second quality is very hard and tough, has a tensile strength of 29,979 pounds per square inch, and is suitable for bearings and the wearing parts of machinery. METEOROL00Y. An extraordinary lurid glow in the western sky after sunset, and in the eastern sky before sunrise, attracted the attention of the world during November and December, 1883. The light occupied the usual lace of the twilight, except that its focus of rilliancy was shifted a little to the southeast, but was much brighter, was of a deeper red, the colors were more varied and turbid, and it rose to a greater height and was longer continued. It also did not appear at the instant of sunset, but a few moments later, after the lapse of an interval of comparative darkness. A description given by an observer in Umballah, India, will give a correct idea of the spectacle as it was seen everywhere. “The sun,” he says, “goes down as usual, and it gets nearly dark, and then a bright red and yellow and green and purple blaze comes in the sky, and makes it lighter again.” The phenomenon began to excite attention in the eastern part of the United States about the 27th of November, when it appears to have reached its culmination in America and Europe. The western sky was illuminated as if by the light of a great conflagration, and fire-alarms were sounded in many places. The spectacle was remarked on the Pacific coast a week previous to this; in Europe early in November; and at points in the East Indies and the Pacific Ocean in September. The earliest notices of it seem to have been made in the islands of Rodriguez, Mauritius, and the Seychelles on the 28th of
August, in Brazil on the 30th, and on the Gold Coast of Africa on the 1st cf September. It was observed at Trinidad, in connection with a “blue sun,” on the 2d of September, and at Ongole, India, after the setting of a “green sun,” early in the same month. It was usually associated either with a wholly clear sky or with a sky marked only by light, floating, cirrous clouds. An apparent connection has been traced between the red light and a blue or green coloring of the sun, which was observed in the East Indies and in tropical America early in September. This phenomenon was observed at Panama and Trinidad on the 2d and 3d of that month. At Manila, in the Philippine islands, on the 9th of September, during a light dry mist, the sun appeared green, and diffused over all the bodies it illuminated “a strange and curious greenish hue.” Similar colorations were observed at the same time at Colombo, Ceylon, just before sunset, and at Madras, India, where Prof. C. Michie Smith, of the Christian College, remarked the perfectly rayless and bright silvery-white color of the sun on the 9th and its pea-green color on the next day. This was repeated several days afterward. The appearance of a green color in the sun and in parts of the sky, outside of the red glow, was remarked on several occasions in Europe. One observer in England recorded the appearance at sunset of a greenish and white opalescent haze about the point of the sun's departure, that shone as with a light of its own, near the horizon. “The upper part of this pearly mist,” he says, “soon assumed a pink color, while the lower part was white, green, and greenish yellow.” Another observer described the blue of the sky as changing to green and the green to the ruddy tint, while the sun appeared of a brilliant emerald hue, tingeing every thing with green. Similar phenomena, with variations in detail, were noticed at many places in England and on the Continent, including Berlin, Rome, and Davos Platz, in the high Alps, where the spectacle was very brilliant, and the sun appeared through the day “surrounded by a luminous, slightly opalescent haze, not at all resembling halo or iridescence of vapor.” The red glow and the green sun are regarded as effects of a common cause. The same medium which gives by transmitted light a green color to objects viewed through it will reflect the red rays. In seeking to account for the phenomena, they must be assumed to be due to some peculiar condition of our atmosphere; for if the glow had been produced by any cause outside of the atmosphere, it would have been visible in some form through the night, whereas its duration corresponded tolerably closely with that of ordinary twilight; and the cause must have been co-extensive with the atmosphere, for the glow lasted as long as a twilight, and even longer. The manifestation was not auroral or electrical, for no auroras were seen that could reasonably be associated with it, and no electrical disturbances were mentioned in connection with it, except in a single instance by Prof. C. Michie Smith, of Madras. The theory that it is the result of peculiar conditions of vapor in the air receives a partial support from Prof. Smith's spectroscopic observations, in which all the atmospheric lines usually ascribed to aqueous vapor were very strongly developed. A marked general absorption was also observed in the red. The facts may also be cited in favor of this theory, that Prof. Lockyer has seen the sun green through the steam of a steamboat; that it has appeared green through the mists of the Simplon; that bright-green suns have been remarked by travelers in the Arctic regions; and, as stated by the Rev. G. H. Hopkins, of Cornwall, England, that, in a clear sky, when the disk of the sun sinks below the horizontal line of the ocean, the parting ray is a bright emerald-green. It is, however, difficult, on this theory alone, to account for the persistence of the phenomena for so long a period through all the varying conditions of atmospheric pressure. Dr. F. A. Forel, of Morges, Switzerland, mentions, as against the sufficiency of the hypothesis, that in Switzerland the glow, after having decreased subsequently to the 3d of December, attained a second maximum on the 24th and 25th of that month, when the atmospheric conditions were quite different from those which prevailed in the country at the time of the first maximum. The hypothesis that the spectacle was caused by the presence in the atmosphere of a cloud of “cosmic dust, ” which the earth had met in its course, has received considerable support. It is now believed, on the authority of Prof. Nordenskiöld, who has collected and analyzed a meteoric dust from the snows of uninhabited regions, and of other observers, that the earth is constantly receiving accretions from space of an exceedingly fine matter having a composition like that of meteoric stones. Mr. W. Mattieu Williams, of London, and M. Emile Yung, of Geneva, collected in December unusually large proportions of such a dust from freshly fallen snows—the former in his garden, the latter on the steeple of the cathedral of Saint Pierre at “les Treize-Arbres,” Mont Salève. The theory which has found most general acceptation is, that the phenomena have been produced by the diffusion through the whole atmosphere of the earth of ashes and cinders from the eruption of the volcano of Krakatoa, in the straits of Sunda, which took place on the 26th of August. The most weighty objections to this theory arise out of the difficulty of explaining how the matter ejected from the volcano could have so quickly reached the enormous height at which the source of the glow was certainly situated, and of the difficulty of imagining it to remain suspended in the air for so long a time. The eruption from
Krakatoa, which immensely exceeded in violence any convulsion of the kind known to man, may, however, easily be conceived to have been capable of producing effects far transcending those which could be imagined in connection with any ordinary or with any other extraordinary known eruption. Mr. W. J. Stillman has witnessed explosions of the submarine volcano of Santorin that threw masses of rock weighing many tons to a distance of from half a mile to a mile, and clouds of dust to an elevation of from six thousand to ten thousand feet. Such effects, magnified to correspond with the grander scale of the Krakatoa eruption, might furnish the conditions required. Respecting the second difficulty, Mr. W. H. Preece and Dr. William Crookes have shown that finely divided particles of dust having an electrical charge of the same sign as that of the earth, may be kept suspended in the air for an indefinite time by electrical repulsion. Prof. S. P. Langley has described an ocean of dust of this kind which he observed in 1881 from near the summit of Mount Whitney, occupying a stratum of the atmosphere some six or seven thousand feet above the level of the sea, from which light was reflected red. A similar formation has been seen from the Peak of Teneriffe, constituting apparently a permanent constituent of the atmosphere. Positive evidence is at hand of the presence during the prevalence of red sunsets of a dust of this kind in the atmosphere of Europe. The sediment derived from a snow that fell at Madrid, Spain, on the 7th of December, when examined, was found to contain, besides the ordinary atmospheric dust of the city, particles of volcanic hypersthene, magnetic iron, and volcanic glass. A rain that fell at Wageningen, Holland, on the 13th of December, left very obvious sediments, which, when analyzed by Messrs. Beyerinck and Van Dam, of the Agricultural Laboratory at that place, were found to correspond very closely with ashes brought from Batavia, Java, which were known to have come from Krakatoa; similar sediments were found at Worcester, England, and Storlvdal, Norway, on Nov. 17th, and at Gainsborough and York, England, Dec. 12th. According to Capt. Sir C. Fleming Stenhouse, who was there at the time, the eruption of Graham's island, in the Mediterranean, in 1831, was followed by a series of red sunsets at Malta. White, in his “Natural History of Selborne,” records the prevalence in 1783, from June 23d to July 20th, of a peculiar haze, or smoky fog, during which “the sun at noon looked as black as a clouded moon, and shed a rust-colored, ferruginous light on the ground and floors of rooms, but was particularly lurid and blood-colored at rising and setting.” All this while, “Calabria and part of the isle of Sicily were torn and convulsed with earthquakes; and about that juncture a volcano sprang out of the sea on
the coast of Norway.” The same phenomenon is alluded to in Cowper's “Task "; and it is ascribed in Mrs. Somerville's “Physical Geography” to the eruption of the volcano Skaptar, in Iceland, which occurred May 8th. The sun was observed of a blue color in England in April, 1821, after an eruption in the island of Bourbon. Dr. Budde, of Constantinople, was told in Algeria, in 1880, that the sun has a decidedly blue color when seen through the fine dust of the desert. Mr. Edward Whymper has described the green suns and ruddy sky effects through a cloud of volcanic dust from Cotopaxi in language precisely applicable to the phenomena under consideration. Extremely brilliant colorations of the sky have been often mentioned in connection with a particular tropical belt. Col. Stuart Wortley, who had already remarked the unusual colors of the sunsets during a series of eruptions of Vesuvius, was greatly impressed with the gorgeous coloring of the tropical skies, which only occurs in certain latitudes and in welldefined belts, and suggests that it may be the result of a constant stream of volcanic matter thrown out by the great volcanoes in the mountain-ranges of South America and elsewhere, forming an almost permanent stratum. In connection with this supposition may be noticed the interesting coincidence, mentioned by Mr. Lockyer, that the volcanic ashes were in the present case, even before they reached India, taken by an upper current from the east, “in a straight line via the Seychelles, Cape Coast Castle, Trinidad, and Panama, to Honolulu—in fact, nearly back again to the straits of Sunda.” It is possible to combine the theory that ascribes the phenomena to aqueous vapor with that which attributes them to volcanic or meteoric dust, by supposing that the dust may act as a nucleus for the condensation of any vapor that may exist at its level, as ordinary city dust and smoke have been found to act as the nucleus for fogs. Annual Rainfall in the United States.—Lieut. H. C. Dunwoody has compiled, under the direction of the Signal Service of the United States, a series of tables with accompanying charts, showing the geographical distribution of the average monthly and the average yearly rainfall at different points in the country, as determined from observations regularly taken at the SignalService stations and army posts, from the establishment of the Meteorological Bureau of the Signal Service, in 1870, to January, 1881. The accompanying map shows the general result of the observations by indicating the average annual precipitation throughout the United States during the ten years over which they have extended. The region of heaviest precipitation appears from it to be a narrow strip along the coast of Washington Territory, where alone more than 80 inches of rain fall during the year. The regions of the next heaviest rainfall, between 70 and 80 inches annually, are a narrow strip back of this one, a small section
on the eastern coast of Florida, and another small district south of Cape Hatteras. The most extensive district of the next heaviest annual precipitation, from 60 to 70 inches, is around the northeastern borders of the Gulf of Mexico, in southeastern Louisiana, southern Mississippi and Alabama, and western Florida; while narrower regions of equal precipitation are found in western Washington and Oregon and northwestern California, eastern Florida, and eastern North and South Carolina. In the mass of the Southern States south of North Carolina and Kentucky and east of the Indian Territory and Texas, the mean annual rainfall is between 50 and 60 inches. This region is surrounded on the north and west by two belts, the more remote and more arid one of which is the wider, which together include the bulk of the States north of 36° 30', and east of the Mississippi river, most of Iowa, Missouri, and Arkansas, and eastern Kansas, Indian Territory, and Texas, in which the amounts of annual precipitation are respectively from 40 to 50 inches and from 30 to 40 inches. West of the western edge of the latter zone is a comparatively narrow region in which the rainfall is between 20 and 30 inches annually; while west of this is a broad region, reaching over the Rocky mountains, and to the Columbia river in the Northwest, in which the mean annual precipitation is between 10 and 20 inches. The rainfall begins at the Columbia river again to increase, in narrow belts, toward the west, till it reaches its culmination in the region of greatest precipitation, already mentioned, on the Pacific coast. The most arid regions in the United States are in Nevada and Arizona, and a district in southeastern New Mexico, where the mean annual precipitation does not amount to ten inches. METHODISTS. I. Methodist Episcopal Church.The summary of the statistics of this Church, as they are given in the “Minutes of the Annual Conferences” for 1883, is as follows: Number of annual conferences................... 99
Number of mission districts..................... 14
For American Bible society....