« AnteriorContinuar »
very much neglected till the attention of the learned were directed to them by Sir H. Davy; and Mr. Dalton had all the merit of being the original founder of this doctrine. Mr. Dalton is certainly deserving of great praise for what he has done. He revived the theory when it was entirely forgotten, and supported it with much ability; extending its empire, and showing its agreement with a great number of facts. Of all the authors who have written on it, Sir H. Davy, in the present work, has taken the most comprehensive view of the subject, and introduced, by means of his original researches, the greatest harmony into all its parts. And he, too, has the merit of separating it from the corpuscular philosophy, and of making facts its only foundation. Mr. Dalton, on the contrary, appears to be a fond disciple of Leucippus and Democritus, who, above 2,000 years ago, taught that all things were composed' of immutable atoms. This philosopher not only believes in the existence of atoms, but even imagines himself acquainted with their invisible forms, and conceives himself capable of calculating their relative weights and their number in any given volume of elastic fluid. Admitting his premises, his conclusions we will allow are capable of demonstration ; but the existence of atoms, and even of matter itself, must be taken for granted, and does not admit of rigorous proof. We, therefore, consider the science as much indebted to Sir H. Davy for having devested this important theory entirely of its hypothetical dress, and placed it before the eyes of his readers in its proper attitude.
Nothing can show to greater advantage the benefits of the theory of definite proportions than the work before us. Everywhere there is the greatest precision; the compositions of bodies are rigorously ascertained and compared together ; no ingredient is overlooked as insignificant; water in particular, hitherto so much neglected, has received a due attention, as forming a part of the character of the compound. The proportions of the constituent parts of bodies are represented by numbers, and the memory is but little burdened with retaining them, as each simple substance has always the same numerical representative. Thus 15 is the general symbol of oxygen, and 26 of nitrogen, so that when the proportions are known in which they combine together, the weights of the constituent parts are most readily found.
The late progress of this theory has been surprisingly rapid. It now embraces all the substances we are accurately acquainted with. The numbers representing oxygen and chlorine, hydrogen, sulphur, phosphorus, and carbon, and most of the metals, have been determined, and the proportions
in which all these substances combine respectively with each other, is in a great measure ascertained. So that chymistry is now become almost a numerical science, and its operations admit of being reduced to numerical exactness.
The refutation which the author has given of Berthollet's doctrines appears to us to be completely satisfactory. He has repeated some of his experiments, and found them incorrect; others he has explained on more simple principles; and Paff has proved, in some of the particular instances adduced by the French chymist himself, that quantity or mass has no influence in modifying the results, or of enabling weak to overcome powerful attractions. We must confess that this refutation affords us no little pleasure, as Berthollet's views had not the simplicity of truth to recommend them, and their tendency was to create confusion, and to render chymistry an art rather than a science. “If chymical attraction," observes Sir H. Davy,“ be regarded as capricious in its effects, and as tending constantly to produce different arrangements, chymistry is left without a guide, without any certain combinations, and no results of analysis can be perfectly alike: but fortunately for the progress of science, this is not the case : the changes of the terrestrial cycle of events, like the arrangement of the heavens, and the system of the planetary motions, are characterized by uniformity and simplicity; weight and measure can be applied to them, their order perceived, and their laws discovered.”
We cannot, in conclusion, deny ourselves the satisfaction of transcribing the following extract, as a specimen of the ruling impressions which the ardent and successful pursuit of science has left upon the miod of Sir Humphry Davy. “ It is contrary to the usual order of things, that events so harmonious as those of the system of the earth, should depend upon such diversified agents as are supposed to exist in our artificial arrangements; and there is reason to anticipate a great reduction in the number of the undecompounded bodies, and to expect that the analogies of nature will be found conformable to the refined operations of art. The more the phenomena of the universe are studied, the more distinct their connexion appears, the more simple their causes, the more magnificent their design, and the more wonderful the wisdom and power of their AUTHOR.”
We have little doubt that these solemn views of the grandeur and simplicity of the works of God have been useful to Sir H. Davy in the regulatio rof his scientific pursuits, and have given a zest to every object. Nor can we withhold from him the tribute of our thanks, for his virtuous, and, we
hope, successful endeavours in all his public addresses on his favourite science, to impress on the minds of his pupils those sentiments which have afforded to himself so much pleasure and advantage.
In all his illustrations and analogies, (and even his manners have received a tincture from the ruling impressions of his mind,) he seems constantly to bear in recollection the humble and beautiful exclamations of the Psalmist : “ The heavens are thine ; the earth also is thine; as for the world and the fulness thereof, thou hast founded them. The north and the south thou hast created them; Tabor and Hermon shall rejoice in thy name."
SPIRIT OF MAGAZINES.
[From Brady's Clavis Calendaria.]
The accounts rendered by different authors of the history of St. George have been so various in their nature, and some of them blended with such gross absurdities, that the very existence of this great and popular saint has not only been doubted by several modern writers, but by some has been wholly denied; while others have so industriously mixed in one heterogeneous mass, the ancient and well-authenticated account of George of Cappadocia, with that of another George, an abominable and infamous character, who was an Arian bishop, that it has occupied much labour and ingenuity to separate the histories of the two St. George's, and to show, devested of the fables too prevalent in former periods, the real and unsullied history of that St. George who is designed to be commemorated on this day, (April 23,) and who, it clearly appears, was born in Cappadocia, of christian parents, of considerable respectability, though at the period of his birth possessing only a small patrimony. St. George was carefully educated in the belief of the gospel, in the defence of which his father lost his life while the saint was yet of years. Upon the decease of his father, St. George accompanied his mother into Palestine, where they came into possession of a large estate. Dioclesian the tyrant, who knew not of his being a christian, and admired his majestic and noble form, appointed him a commander in one of his legions, with the dignity of a seat in the council. In the twentieth year of his age he lost his maternal parent, and wholly dedicated himself to his military duties, in which he became eminently distinguished: but during the height of his reputation, the persecution of the christians burst forth with increased violence and aggravated cruelty ; upon which St. George withdrew himself from the service of the tyrant, whom he had the courage publicly to upbraid, in the senate, with his barbarities; and openly distributed his vast fortune for the support of those against whom the persecutors of christianity, headed by the
emperor, were exerting their utmost malice. The emperor, amazed and irritated at the daring boldness of St. George, seemed at first determined upon his destruction; but the many services rendered to him by that great man induced him to suspend his vengeance, and he endeavoured by every means in his power to continue the hero in his service. Alike unmoved by promises of aggrandizement, and unawed by threats, St. George continued firm in his opposition to the tyrannies of the hardened emperor; for which, after having several times endured the torture, he was ignominiously drawn through the city of Lydda, and beheaded on the 23d day of April, 290. The surviving christians buried his mutilated remains, the sepulchre containing which remained in tolerable preservation until the year 1180: and we find, that his head was solemnly translated to the great church built in honour of him in the eighth century, by pope Zachary, who attended the ceremony, accompanied by the whole of the clergy, and most of the laity of Rome.
From these facts sprang those fabulous statements of the combat of St. George with a dragon, to preserve the daughter of a king, who otherwise would have been devoured by the monster; and from that fable, the many others connected with the popular belief of past periods, as may be seen by the history of the Seven Champions of Christendom, as well as in various other ancient histories and ballads.
St. George having been a soldier of superior rank, was not unnaturally depicted on horseback, armed cap-a-pie, which appears to have been the practice before the eleventh century; and when at a later period, the story of the dragon's overthrow became a favourite with the multitude, the addition of that monster was a necessary appendage, to give consistency to the legend, and make it accord with the new but erroneous history of the saint. Whether, however, the fabrication of this fictitious part of the saint's life and actions originated in monkish craft, to gain a superstitious power over the ignorant multitude, or whether the whole of that story was meant symbolically, to typify that Christ's soldier and knight should always be ready manfully to combat against the dragon, or great beast, mentioned in the Apocalypse, and all other enemies of the church, is a matter of doubt. In accounting for the strange introduction of the insignia of St. George, there are not wanting advocates for both these arguments, though the latter has met the most able supporters, who contend, with much apparent historical authority, that the hieroglyphical representation of the saint preceded the fable, and not the fable the emblem; and indeed it is scarcely possible to believe