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ence, every lover of wisdom, with a History of the Science.-* Josephus satisfaction the most perfect and en- informs us, that Astronomy was untire.
derstood among the antediluvians ; May this society still prosper! and that it was particularly studied by Like the tree, deep-rooted and well the patriarch Seth, and his posterity. watered, may it still flourish ; per- Unless we can credit this account of fuming the air with its fragrance, Josephus, the ancient Chaldeans must adorning the earth with its verdure, be acknowledged as the fathers of and benefiting the world by its fruit! Astronomy. The lofty summit of the May it never want the beams of a vivi- tower of Babel; the extensive and fying sun, nor the refreshing breezes, level plains of that country; the renor the fruitful showers of heaven! | freshing coolness of the night, after May it continue the seat of all that is the oppressive beats of the day; an noble and elegant; of all that is enter- unbroken horizon; a pure and serene taining and instructive in learning and sky-all conspired to engage that peophilosophy; the boast and ornament ple to contemplate the extent of the of these towns, to the end of time ! heavens, and to observe the motions
Such are the wishes of a stranger; and phenomena of the stars. From a stranger, whom the members of this Chaldea, Astronomy passed into society have received with the atten- Egypt, and from Egypt into Phonetion and kindness of a brother! Such cia; and as the Phoenicians applied the desires of one who is willing to it to the purposes of navigation, they contribute what lies in his power to soon became masters of commerce, the welfare of this institution: The and of the sea. Thales, the chief of best proof of which he now proceeds the seven sages of Greece, who flouto submit.
rished about 600 years before the Definition of Astronomy.-Astrono- Christian era, is said to have brought my is the science which teaches the the science of the stars from Phæniknowledge of the heavenly bodies; cia into Greece ; and to have taught their magnitudes, distances, motions, the reason of the length and shortness periods, eclipses, and order.
of the days, the causes of eclipses, and Importance of the Science. Whether other astronomical phænomena. In we consider the objects which Astro- the hands of the Greeks, the science nomy sets before us; or, the accuracy was cultivated with assiduity and sucand precision of most of its proofs and cess ; and the names of Pythagoras, calculations; or, the service which, Anaximander, Meton, Pythias, Arin various ways, it renders to the na- chimedes, Aristotle, and others, are tions of the earth, it is, and ever famed in the annals of the stars. The must remain, the most valuable, inte- Romans, the Arabian princes, and at resting, and sublime science, which last the princes of Europe, became can possibly engage the attention of the patrons and promoters of Astro
This noble science, not only nomy. deserves our regard, as a matter of But it is from the sixteenth century curiosity, or rather of astonishment to the present time ; from the days of and wonder; and as answering the Copernicus to those of Herschel and most important purposes for the good Olbers, that this sublime science has of civil society ; but still more so, as it continued to advance towards perfecopens a scene, which impresses the tion, with a steadiness and glory so mind with the most exalted, and con- peculiar to itself. And in all that sequently, the most just and correct interval, if we except the very days ideas, of that eternal and omnipotent in which the immortal Newton sketchBeing, who contrived, made, and ed the laws of the universe, perhaps still upholds, the whole! When sur- Astronomy, perhaps science of no veying those stupendous works, which kind, has ever witnessed a more brilmove with such order and harmony through the immeasurable fields of space, we are led to exclaim,
* In the first volume of the Imperial Maga
zine, we gave, through several numbers, the “ These are thy glorious works, Parent of History of Astronomy at large, which would good,
seem to supersede the necessity of this. But Almighty! thine this universal frame
as the lecture would be incomplete were this Thus wondrous fair! thyself how wondrous historical sketch omitted, it is retained, that then!
order and uniformity may be preserved.
liant period, than that, in which it is embarrassed and perplexed, that few our honour and happiness to live. persons have embraced it; and no
Systems.--Although there have been wonder, if, as some of the biogramany schemes and hypotheses con- phers of Tycho intimate, his vanity to cerning the heavenly bodies, yet there become the founder of a system, had have been only four which have attain- too large a share in its production. ed to any thing like authority and per- The third system is denominated the manence in the world. The first of Cartesian, from its author Des Cartes, these is the Ptolemaic system, so a French philosopher, of the sevencalled from Claudius Ptolemy, a na- teenth century; and a man of a spetive of Pelusium, in Egypt, who made culative, bold, prodigious genius. bis last astronomical observation, on His reputation in foreign nations apWednesday the 2d of February, 141. pears on his monument, which conThe system which is distinguished by sists of four faces, inscribed with so his name, is contained in his celebra- many encomiums. It was erected ted book, called “ The Great Syntax- at Stockholm, where he died in the is;" which book reduces to order the year 1650. observations of the ancient astrono- The system of Des Cartes, though mers, and is, I believe, the first book very artfully contrived, yet carries which ever set forth regular tables with it more of the air of a ROMANCE, of the sun, moon, planets, and fixed than of a just and solid philosophy. stars.
It supposes the planets to be driven The Ptolemaic system supposes the round the sun, in a vortex or whirlearth to be at rest in the centre, and pool of subtile matter ; and that the that the heavens, solid and incorrup- vast regions of space being full of this tible, revolve round it from east to subtile matter, there is an infinite numwest, carrying along with them all the ber of planetary vortices, every fixed planets and tixed stars. The diverse star being the centre of its distinct motion of the planets, this system ac- vortex. That this whirlpool scheme counts for, by assigning to each of of the Cartesians is a mere fiction, is them its respective orb; and the outer- evident from the following consideramost orb, the primum mobile of the tions. ancients, was supposed to communi- 1, That comets, which pass very cate motion to all the rest. Although freely in the heavenly spaces, taking philosophers of the present day smile their prodigious journeys to and from at this system as absurd and impossi- all parts, move in orbits which interble ; yet it should be remembered, sect the orbits of the planets at all that the world was content with it for angles. So that if the comets move many ages; and that it was once look- in a vortex, as well as the planets, ed upon as founded on invincible de- there would be two vortices, moving monstration, and as placed beyond in different, perhaps in opposite di. the reach of controversy and the rections, in one and the same place, fluctuations of opinion: a circum- at one and the same time ; wbich is stance this, which calls for a degree of absurd. modesty and hesitation, about much, 2. According to the laws of mechavery much, of our knowledge.
nics, it is evident, that it matter of The second system is called the Ty- any kind move in a vortex, which is chonic system, from its inventor, Ty- elliptical, it must move the swiftest in cho Brahé, a noble Dane, who ac- that part of the ellipse which is the quired great celebrity as an Astrono- most strait, narrow, and compressed. mer, in the latter half of the sixteenth But according to the laws of Astronocentury. In this system there are sup- my, the planets whieh move in elliptiposed to be two centres ; the earth, cal orbits, when in that part of their the centre of the universe or firmament orbits which is the most contracted of stars, around which they revolve in and compressed, viz. in aphelion, then 24 hours; and the sun, the centre of move the slowest. the orbits of Mercury, Venus, Mars, 3. This doctrine of vortices is not Japiter, and Saturn; around which supported by any phenomena of nathey are carried in their respective pe- ture, with which we are acquainted. riods, the same as the sun is supposed “If,” says Sir Isaac Newton, “three to be carried round the earth in its equal round vessels be filled, the one
This hypothesis was so with water, the other with oil, the
third with molten pitch, and the I be superseded for two thousand liquors be stirred about till they have years. alike acquired a vorticle motion ; the The true theory of the heavens was pitch by its tenacity will lose its mo- revived in the sixteenth century, by tion quickly; the oil, being less te. Nicholas Copernicus, a prebend of nacious, will keep it longer; and the Thorn, in Poland; and hence is called water, being least tenacious of the the Copernican system. Copernicus three, will keep it longest, but yet died in the year 1543: he was an exwill soon lose it. Whence it is easy to cellent classical scholar; a profound understand, that if many contiguous mathematician ; and a most acute and vortices of molten pitch were each of laborious observer of celestial phenothem as large as those wbich are sup
His book, “ De orbium cælesposed by some to revolve around the tium revolutionibus,” which contains sup and fixed stars ; yet these and all his theory, was a work of long and their parts, would, by their stiffness arduous toil; it was printed under the and tenacity, communicate their mo- management of two of his philosophition one to another, until they all rest- cal friends, and a copy of it was put ed among themselves. Vortices of oil, into his hands just before he expired. or water, or some more fluid matter, But the denominating terms, Pythamight continue longer in motion; but gorean and Copernican, are now giving unless the matter were destitute of place to the more Anglicized, and tenacity, and attrition of parts, and perhaps more significant appellative, communication of motion, (which is Newtonian. In the latter part of the not to be supposed,) the motion would seventeenth century, it pleased the Alconstantly decay, till finally there mighty, in pity to the darkness of manwould be an universal rest.”
kind, and to throw a stronger light It would have been a waste of time upon his own matchless and amazing thus to combat the Cartesian hypo- works, to visit our hemisphere with thesis, but for the very recent attempts that bright and steady luminary, the which have been made to revive it. great Sir Isaac Newton. Endowed The temerity with which Sir Richard with a compass of soul, high, and vast, Philips has discarded the Newtonian and profound ;-with a penetration philosophy, and substituted that of which could look through nature, and Des Cartes, has led some to doubt scan her mighty laws ;-with an intelwhether the philosophic knight-errant lectual industry equal to the most gibe in reality sincere. But whether Sir gantic enterprise ; - with a temper Richard, and the rest of the Cartesian calm, tranquil, and devout,—the imastronomers, be sincere or insincere, it mortal Newton rose far above the is manifest their situation calls for our common level, even of learned and philosophic commiseration : the poor scientific men; and by his single powfellows having got into a whirlpool, er, reared a fabric of mathematical from which they cannot get out, are and experimental philosophy, which carried round and round a centre of must for ever stand the boast of true absurdity, in a vortex of nonsense ! wisdom, and the terror of idleness,
The fourth system, which we do not ignorance, and pride. hesitate to pronounce the true one, is that theory of Astronomy which now
( To be concluded in our next.) almost universally prevails, and which is certainly destined to be received as the rule of the sun, moon, and stars, as long as sun, and moon, and stars, endure. This system has sometimes In great matters of public moment, been classically denominated the Py- where both parties are at a stand, thagorean system, because it was un- and both are punctilious, slight conderstood and taught by Pythagoras, descensions cost little, but are worth an ancient Greek philosopher. It is a much. He that yields them is wise, remarkable fact in the history of inasmuch as he purchases guineas science, that the true scheme of the with farthings. A few drops of oil universe sbould have been known and will set the political machine at work, published by Pythagoras, more than when a tun of vinegar would only 500 years before the Christian æra ; corrode the wheels, and canker the and then that it should slumber and movements.
ADVANTAGES OF CONCESSION.
25 Chemical Essays.
26 CHEMICAL ESSAYS, -BY STUDIOSUS. collected over water in the following
The pneumato-chemical, or MR. EDITOR.
pneumatic apparatus, was first inventSir,- If you think the following Essay ed by Dr. Priestley, which consisted on Oxygen, worthy a place in the co-of nothing more than a common tub, lumns of your valuable miscellany, with a shelf in it. He afterwards for which it has been purposely writ- used a most elegant apparatus, which ten, an early insertion will gratify. I the Duke of Rochefoucault sent him. Should it meet your approbation, it This trough may be made of any size, shall be followed by a second, on Ni- but should not be less than a foot in trogen, and a third on Atmospheric depth ; the shelf is to be placed on Air,
one side only, and about three inches I am Sir,
from the top. Having filled the whole With the most profound respect, with water, for at least an inch above
STUDIOSUS. the shelf, we are next to fill a jar or
glass receiver with comthon water; Essay 1st.- Oxygen.
and having placed the open end of it
upon the shelf, we are to introduce The word Oxygen is of Greek extrac- the beak of the retort into the pneution, and signifies to generate acidity. mato-chemical, immcdiately under Oxygen Gas was first discovered by the open end of the receiver, when airDr. Priestley, in 1774, who called it bubbles will be seen to arise through dephlogisticated air. In 1775, it was the water into the receiver, and disdiscovered by Mr. Sheelc, without any place the water. In this way we may previous knowledge of the discovery proceed till we have obtained a sufliof Dr. Priestley. Mr. Sheele gave it ciency for use. 3d. From the Hyperthe name of empireal air. It first oxymuriate of soda, or potass. Put received the name of vital air from into a retort any quantity of either of Condorcet, and that of Oxygen Gas these salts, apply the heat of a lamp, from Lavoisier. We are acquainted and Oxygen, in the greatest purity, with many substances, from which will be liberated, which may be colOxygen Gas may be obtained. A-le over water, as previously demongst others, it may be procured scribed. Nitrate of potass is another from the green leaves of vegetabies, substance which is frequently used for from the oxydes of manganese, lead, obtaining Oxygen Gas; but trusting or mercury, from the hyperoxymuriate that the foregoing processes will be of soda, or potass.
found sufficient, we will now proceed Ist. From the fresh leaves of vege- to investigate its properties. tables. Fill a large receiver, or bell Oxygen Gas is invisible, and colourglas, with water, and invert it on a less, like common air. Like common broad dish, which is to be likewise air, it is also highly elastie, and cafilled with that fluid; introduce fresh pable of indefinite expansion and gathered leaves; expose the whole to compression. Its specific gravity is the rays of the sun, and pure Oxygen 135o, it is therefore 740 times lighter will be disengaged, which will gradu- than the same bulk of atmospheric air. ally displace all the water, and occupy Its weight to that of atmospheric air its place. 2d. From the black oxyde being as 1103 to 1000. It is not senof manganese. Put into a retort of sibly absorbed by water, though left glass any quantity of the black oxyde in contact with that fluid for a great of manganese, add as much sulphuric length of time. It is entirely absorbacid as will form the whole into a thin able by the combustible bodies, which, paste, apply the heat of a lamp, and in consequence of disengaging its Oxygen Gas, sufficiently pure for all caloric and light, produce heat and common purposes, will be liberated. flame. If combustible bodies be burnt If we are wishful to obtain it on a in Oxygen Gas, and the experiments more extensive scale, the following are conducted with accuracy, we shall process will be preferable. Procure find the product increased in weight an iron retort, and baving introduced just the quantity of Oxygen consumed. a sufficient quantity of the black oxyde By experiments, which shall be notiof manganese, expose the retort to a ced in a following Essay, it hath been red heat, and Oxygen Gas will be proved that Oxygen constitutes about evolved in abundance, which may be · 22 in every 100 parts of atmospheric No. 36.---Vol. IV.
air, or, if the calculation be made by the atmosphere, passes from its origiweight, 23 parts. It has also been nal yellow colour, through several difproved beyond a doubt, that no ani- ferent shades, till it assumes that of mal whatever can live for a moment, a dark purple; this I have had shewn in air previously deprived of all its me several times by an intelligent Oxygen; and that animals will live dyer, of Manchester; and it is a well six times as long in the same quantity known fact, that when woollen goods of Oxygen Gas, as in common atmo- are taken out of an indigo vat, they spheric air. Oxygen is therefore ne- are generally of a beautiful green, but cessary to animal life.
in the course of one or two minutes Oxygen necessary to combustion.-In- | they have absorbed a sufficient dose troduce into a glass jar, or receiver, of Oxygen, to convert them into a filled with Oxygen Gas, a lighted ta- dark blue. per, and it will burn with great bright- Germination.—That germination does ness, and produce a much greater not depend upon the seed alone, but degree of heat than if burnt in atmo- requires some external cause to effect spheric air. Blow the taper out, re- it, is now generally acknowledged. introduce it, and the flame will be in- Seeds will not germinate, unless a stantly rekindled. If we introduce a certain degree of heat and moisture lighted taper into a well-closed jar of have access to them; nor will they common air, it will be almost im- then germinate, unless atmospheric mediately extinguished; if we re- air be present. It has been proved peat the experiment, substituting, Ox- by well-conducted experiments, that ygen Gas, we shall find it to burn seeds will not germinate in the vacusome time. We have said that Oxy- um of an air-pump, but as soon as gen is not absorbed by water; but, by atmospheric air is admitted, they bemeans of strong pressure, however, gin to germinate. Hence the wellit may be made to take up half its known fact, that seeds will not gérown bulk, which it will retain in solu- minate if placed at too great a depth tion. Though water thus impregnated below the earth's surface. The expedoes not essentially differ from com- riments of Sheele, Gouch, Archand, mon water, in either taste or smell, &c. fully prove that seeds will not yet it has been administered in several germinate unless oxygen be present, diseases with decided success. Dr. and that it is not atmospheric air, but Higgins caused a young man to the Oxygen it contains, which is nebreathe Oxygen Gas for several mi- cessary to the process, for seeds' will nutes, when his pulse, which was at not germinate in either azote, carbo64, soon rose to 120 beats in a minute. nic acid, or hydrogen gas. Dr. HumIt is upon this principle that pure bolt found that seeds which do not Oxygen has been used with such suc- commonly germinate in our climate, cess in suspended animation.
even in our hot-houses, were capable Effect of Oxygen upon the blood.- of germinating after a few days imThe blood when it has arrived at the mersion in weak oxymuriate acid. lungs is of a dark purple colour, Oxygen combines with all the known which is owing to the superabundance metals, with every combustible subof carbon which it has received in its stance, and with the greater number course of circulation through the of substances of which the animal and body; it here becomes converted into vegetable kingdoms consist. When a red oxyde, by the great quantities by this combination they become oxof Oxygen it is continually receiving ydes, they are said to be oxydized; through the agency of the lungs, and when converted into acids, oxyginibecomes of a bright and florid red. zed. When speaking of atmospheric Put a little blood into a small vessel of air, I shall say more on this important Oxygen Gas, shake the vessel, and subject. the gas will have become partly ab
(To be continued.) sorbed by the blood, which will assume a bright scarlet colour. Lavoi- [We shall feel ourselves obliged if STUDIsier has shewn that a man consumes,
Osus will forward the continuation of his Es. in the space of 24 hours, not less says as soon as possible, that our arrangethan 32 ounces, troy, of Oxygen Gas. beg all our other Correspondents, whose arti
ments may not be thrown into disorder. We Effect upon colours. — The liquor cles are announced to be continued, to take made from Whelk, upon exposure to this hint.) EDITOR.