DESCRIPTIVE ASTRONOMY.
Mercury, the nearest planet to the sun, is a globe of about 3140 miles in diameter, rotating on its axis in 24 hours and 5 1-2 minutes, and revolving round the central luminary, at a distance of 37,000,000 of miles, in 88 days.—From the earth it can only be seen occasionally in the morning or evening, as it never rises before, or sets after the sun, at a greater distance of the time than 1 hour and 50 minutes. It appears to the naked eye as a small and brilliant star, but when observed through a telescope, is horned like the moon, because we only see a part of the surface which the sun is illuminating. Mountains of great height have been observed on the surface of this planet, particularly in its lower or southern hemisphere. One has been calculated at 10 3-4 miles in height, being about eight times higher, in proportion to the bulk of the planet, than the loftiest mountains upon earth. The matter of Mercury is of much greater density than that of the earth, equalling lead in weight; so that a human being placed upon its surface would be so strongly drawn towards the ground as scarcely to be able to crawl.
Venus is a globe of about 7800 miles in diameter, or nearly the size of the earth, rotating on its axis in 23 hours, 21 minutes, and 19 seconds, and revolving round the sun, at the distance of 68,000,000 of miles in 225 days.—Like Mercury, it is visible to an observer on the earth only in the morning and evening, but for a greater space of time before sunrise and after sunset. It appears to us the most brilliant and beautiful of all the planetary and stellar bodies, occasionally giving so much light as to produce a sensible shadow. Observed through a telescope, it appears horned, on account of our seeing only a part of its luminous surface. The illuminating part of Venus occasionally presents slight spots. It has been ascertained that its surface is very unequal, the greatest mountains being in the southern hemisphere, as in the case of both Mercury and the Earth. The higher mountains in Venus range between 10 and 22 miles in altitude. The planet is also enveloped in an atmosphere like that by which animal and vegetable life is supported on earth; and it has consequently a twilight. Venus performs its revolution round the sun in 225 days. Mercury and Venus have been termed the Inferior Planets, as being placed within the orbit of the Earth.
The Earth, the third planet in order, and one of the smaller size, though not the smallest, is important to us, as the theatre on which our race have been placed to 'live, move, and have their being.' It is 7902 miles in mean diameter, rotating on its axis in 24 hours, at a mean distance of 95,000,000 of miles from the sun, round which it revolves in 365 days, 5 hours, 50 minutes, and 57 seconds. As a planet viewed from another of the planets, suppose the moon, 'It would present a pretty, variegated, and sometimes a mottled appearance. The distinction between its seas, oceans, continents, and islands, would be clearly marked; they would appear like brighter and darker spots upon its disc. The continents would appear bright, and the ocean of a darker hue, because water absorbs the greater part of the solar light that falls upon it. The level plains, (excepting perhaps, such regions as the Arabian deserts of sand) would appear of a somewhat darker color than the more elevated and mountainous regions, as we find to be the case on the surface of the moon. The islands would appear like small bright specks on the darker surface of the ocean; and the lakes and mediterranean seas like darker spots or broad streaks intersecting the bright parts, or the land. By its revolution round its axis, successive portions of the surface would be brought into view, and present a different aspect from the parts which preceded,'—(Dick's Celestial Scenery, 135.)
The form of the earth, and probably that of every other planet, is not strictly spheroidal; that is, flattened a little at the poles, or extremities of the axis. The diameter of the earth at the axis is 56 miles less than in the cross direction. This peculiarity of the form is a consequence of the rotatory motion, as will be afterwards explained.
Late Foreign News.
The steamer Hibernia arrived at Boston on Saturday last, thirteen days from Liverpool.
The British Government and people have manifested so much violent opposition to the marriage of the youngest son of Louis Phillipe to a sister of the Queen of Spain, that the celebration of the nuptials has been postponed for the present, if not forever; and there is apparent danger of a rupture between England and France on this account.
In Spain, Don Carlos having escaped from imprisonment, it is expected that a serious insurrection will immediately take place.
Property to the amount of $800,000 has been destroyed by incendiary fires at Leipsic. A line of electric telegraph has been put in operation between Brussels and Antwerp.
Twenty thousand bales of cotton were sold at Liverpool on the 14th of September.
Latest from the Army.
According to recent intelligence by private letters, Gen. Kearney has taken quiet possession of Santa Fe, notwithstanding the considerable preparations which the Mexicans had made to defend it. Gen. Armijo had assembled 5000 troops to defend the Canon Pass, but on account of the disaffection and insubordination of his officers and men, he was constrained to retreat on the approach of a few companies of Americans.
Gen. Taylor had advanced steadily, though slowly on Monterey, and has probably ere this, taken possession, notwithstanding the strong force, and full supply of well mounted cannon, concentrated to oppose him. Should he prove successful in this, it would seem that Mexico is destined to fall under the protection of the United States, whether our Government desires it or not. What can we do? The Mexicans will neither treat nor fight; and although our armies move as slow as possible, they cannot well avoid progressing through the country in time, and are bound to furnish protection as far as they go. We shall see.
The Sea and Wave Roaring.
The steamer Great Western, which arrived at this port last week, reports having encountered one of the most terrific storms ever known on the Atlantic Ocean. Capt. Mathews is said to have remarked that at three different times the ship was approached by seas of such magnitude and power that he thought destruction inevitable; but unexpectedly each broke just before reaching the vessel. The passengers assembled in the cabin where they joined in religious service, and in the solemn administration of the Lord's supper. Their lives were preserved, but some of them appeared to forget their obligations to their preserver very quick after getting safe on shore.
An American Slave in England.
Douglas, who escaped from slavery and found his way to England, has received marked attention from the nobility and gentry of England. He has attended their soirees, occupied the most honorable positions at their dinner parties, rode in their carriages, flirted with their daughters, walked arm in arm through their gardens with lords, viscounts, counts and mayors of cities.
Many of the girls employed in the mills of the Nashua Corporation, have refused to work by candlelight. They may be right.
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Observations on the more recent Researches concerning the operations of the Blast Furnace in the Manufacture of Iron.
BY DR. J. L. SMITH.
The great difference existing between metallurgical operations of the present day, and those of a former period, is owing chiefly to the ameliorations produced by the application of the science of chemistry to the modus operandi of the various changes taking place during the operations, from their commencement to their termination.
Copper and some other metals are now made to assume forms in the chemist's laboratory, that formerly required great artistical skill for their production—the chemist simply making use of such agents and forces as are at his command, and over which he has, by close analytical study, acquired perfect control. Our object, at present, is only to advert to the chemical investigations more recently made on the manufacture of iron, treating of those changes that occur in the ore, coal and flux, that are thrown in at the mouth of the furnace, and in the air thrown in from below. For most that will be said on this subject, we are principally indebted to the recent interesting researches of M. Ebelman.
The importance of a knowledge of the facts to be brought forward, in this article, will be apparent to every one in any way acquainted with the manufacture of iron. It will be seen that the time is not far distant when the economy in the article of fuel will amount in value to the present profit of many of the works. The consequences must be, that many of those works that are abandoned will be resumed, and others erected in localities formerly thought unfit.
It is well known that the blast furnace is the first into which the ore is introduced, for the purpose of converting it into malleable iron, and much, therefore, depends upon the state in which the pig metal passes from this furnace, whether subsequent operations will furnish an iron of the first quality or not.
In putting the blast furnace into operation, the first step is to heat it for some time with coal only. After the furnace has arrived at a proper temperature, ore, fuel and flux, are thrown in alternately, in small quantities, so as to have the three ingredients properly mixed in their descent. In from 25 to 48 hours from the time when the ore is first thrown in, the entire capacity of the furnace, from the tuyer to the mouth, is occupied with the ore, fuel and flux, in their various stages of transformation.
In order to explain clearly, and in as short space as possible, what these transformations are, and how they are brought about, we may consider:—1. The changes that take place in the descending mass, composed of ore, fuel and flux. 2. The changes that take place in the ascending mass, composed of air and its hygrometric moisture, thrown in at the tuyer. 3. The chemical action going on between the ascending and descending masses. 4. The composition of the gases in various parts of the furnace during its operation. 5. The causes that render necessary the great heat of the blast furnace.
1. Changes that take place in the descending mass, composed of ore, coal and flux.—By coal is here meant charcoal; when any other species of fuel is alluded to, it will be specified. In the upper half of the fire-room the materials are subjected to a comparatively low temperature, and they lose only the moisture, volatile matter, hydrogen, and carbonic acid, that they may contain; this change taking place principally in the lower part of the upper half of the fire-room.
In the lower half of the fire-room, the ore is the only material that undergoes a change, it being converted wholly or in part into iron or magnetic oxide of iron—the coal is not altered, no consumption of it taking place from the mouth down to the commencement of the boshes.
From the commencement of the boshes down to the tuyer, the reduction of the ore is completed. Very little of the coal is consumed between the boshes and in the upper part of the hearth; the principal consumption of it taking place in the immediate neighborhood of the tuyer.
The fusion of the iron and slag occurs at a short distance above the tuyer, and it is in the hearth of the furnace that the iron combines with a portion of coal to form the fusible carburet or pig-iron. It is also on the hearth that the flux combines with the siliceous and other impurities of the ore. This concludes the changes which the ore, coal and flux, undergo, from the mouth of the furnace to the tuyer.
If the fuel used be wood, or partly wood, it is during its passage through the upper half of the fire-room that its volatile parts are lost, and it becomes converted into charcoal. M. Ebelman ascertained that wood, at the depth of ten feet, in a fire-room twenty-six feet high, preserved its appearance after an exposure for 1 3-4 of an hour, and that the mineral mixed with it preserved its moisture at this depth; but three and a half feet lower, an exposure of 3 1-4 hours reduced the wood to perfect charcoal, and the ore to magnetic oxide. The temperature of the upper half of the fire-room, when wood is used, is lower than in the case of charcoal, from the great amount of heat made latent by the vapor arising from the wood. In the case of bituminous coal, Bunsen and Playfair find that it has to descend still lower before it is perfectly coked.
After the wood is completely charred, or the coal become coked, the subsequent changes are the same that happen in the charcoal furnaces.
To be continued.
ANIMALCULAE IN WATER.
The fact is generally known that nearly all liquids contain a variety of minute living animals, though in some they are too small for observation, even with a microscope. In others, especially in water that has been long stagnant, these animals appear not only in hideous forms, but with malignant and voracious propensities. The print at the head of this article purports to be a microscopic representation of a single drop of such water, with the various animals therein, and some of the inventors and venders of the various improved filters for the Croton water, would have no objection to the prevalence of the opinion that this water contains all the variety of monsters represented in this cut. But the fact is far otherwise; and it is doubtful whether these animals could frequently be detected in the Croton water, with the best solar microscope. Nevertheless, the fact is readily and clearly established that the Croton water contains a quantity of deleterious matter, which is arrested by the filters; and, on this account, we cheerfully and heartily recommend the adoption of filters by all who use this water, from either the public or private hydrants. To this end we would call the special attention of our city readers to the improved filters noticed under the head of "New Inventions."
Length of Days.
At Berlin and London the longest day has sixteen and a half hours. At Stockholm and Upsal, the longest has eighteen and a half hours, and the shortest five and a half. At Hamburg, Dantzic, and Stettin, the longest day has seventeen hours, and the shortest seven. At St. Petersburg and Tobolsk, the longest has nineteen, and the shortest five hours. At Toreno, in Finland, the longest day has twenty-one hours and a half, and the shortest two and a half. At Wandorbus, in Norway, the day lasts from the 21st of May to the 22d of July, without interruption; and in Spitzbergen, the longest day lasts three months and a half.
Excitement of Curiosity.
The editor of the Cincinnati Enquirer, having been one of a recent excursion party on the opening of a new section of railroad, remarks on the occasion, 'It is really amusing to see the sensation a train of railroad cars produces on all animate beings, human and brute, for the first few times it passes over a section of road. We saw herds of cattle, sheep, and horses, stand for a few seconds and gaze at the passing train, then turn and run for a few rods with all possible speed, stop and look again with eyes distended, and head and ears erect, seemingly so frightened at the tramp of the iron horse as to have lost the power of locomotion. Men women and children also seemed dumbfounded at the strange and unusual spectacle. As the cars came rumbling along early in the morning, they seemed to bring everybody out of bed, all eager to catch a glance as we whirled past. Old men and women, middle-aged and youth, without waiting to put on a rag in addition to their night gear, were seen at the doors, windows and round the corners of log huts and dwellings, gaping with wonder and astonishment at the new, and to them grand and terrific sight.'
[COMMUNICATED.]
At the last special meeting of the National Association of Inventors, called to hear the report on the rights and duties of the Editors of the Eureka, on a resolution offered by one of the Editorial Committee who had been dissatisfied by the proceedings of the 'Acting Editors,' and refused to attend their sittings, it was reported that the 'Acting Editors,' had exceeded their authority, and a majority of the Editorial Committee resigned and a resolution was passed that the resignation should be published in the Eureka, but it has not appeared. Mr. Kingsley, one of the 'Acting Editors,' spoke at the said meeting of having consulted counsel who had declared that the Association were under a legal obligation to furnish Messrs. Kingley & Pirsson with matter for publication in the Eureka, and on the understanding that they had advanced money they were allowed to have the first use of the reports and advertisements of the Association. But as they in effect refuse to publish a resolution of great importance to the reputation of all the parties interested, it is left for the public to decide whether the 'Acting Editors' are in any respect entitled to the name they have assumed for their paper.
One of the Editorial Committee.