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to the Edinburgh Review. It is impossible in this place to do any justice to the argument; but the preceding extract may possibly be of some use in directing the attention of our Scottish readers to a view of the subject, which they are not much accustomed to consider.

The celebrity of some systems of education exclusively carried on by public lectures, has been traced to the local and peculiar attractions which the professorships possess for men of first-rate talents and acquirements, and the inducements which the discharge of their official duties affords for the continual exertion of their powers: And if the principal object of a university were the advancement of learn ing and science, and not the instruction of youth, those systems might be allowed to claim the preference which sacrifice the latter to the former; but if universities have been instituted for the pupils, and not for the professors, the young men who frequent them for the cultivation of their minds, have a right to complain, if their interests are in any instance neglected, though the whole world besides should reap incalculable benefit from the labours of their teachers. It has been stated by Doctor Adam Smith and other writers, that the education which is most likely to produce a man of solid learning and knowledge, is to impose upon him the necessity of teaching others, and, above all, to oblige him to teach by compositions of his own and in public; and it is an undoubted fact, that a large proportion of the most valuable acquisitions in literature and science have in all ages been made by those whose talents were called into exertion by the instruction of youth. But when the question is, to what university a young man is to be sent,

are parents or guardians to postpone his immediate advantage to any benefits that may arise to future ages from contributing their individual assistance in the production of two or three professors of splendid talents to adorn the history of science, and bestow a temporary celebrity on the scene of their labours? If there be any truth in the position, that to promote the boundaries of human knowledge, and to cultivate the minds of youth, are occupations totally distinct from each other, and not unfrequently at variance, it must be admitted to be a great error and a gross delusion to confound the fame of public professors in the literary world with the merits of a system of edu cation with which they happen to be connected.

We have endeavoured to render this account of the studies pursued at Oxford as impartial as possible; and have taken care not to confound what is efficient with what is nominal: we fear, however, that it is in some measure imperfect, as our limits will not permit us to enlarge on the various important topics which have hastily passed before us in the course of the preceding observations. We had intended to conclude with some notice of the arguments by which the authors quoted above have defended the importance which is attached to classical learning at Oxford; but we have not room for the ample consideration which they demand, and we cannot hope to say any thing very new or interesting in this place on a subject on which so much has been already written. One opinion is implied in what has been said above, that, even admitting classical studies to possess all the merits for which their fondest advocates contend, one year may be profitably subtracted

from the time now employed in preparation for the public examinations, and devoted to the study of natural and moral philosophy and political economy. It cannot be disputed that the present system is calculated to produce habits of accurate investigation, and laborious exertion, totally unknown in those seminaries where education is carried on by the popular mode of public lectures; though we are inclined to think that these and all the other advantages of

this system are too dearly purchased by the neglect or exclusion of the sciences already mentioned during a period of time so inconsistent with the shortness of human life. Were the alteration made which we have ventured to suggest, there cannot be a doubt that Oxford would soon afford the model of a system of public education far more perfect than any of which the world can at present boast.

REVIEW OF SCIENCE.

IN the last volume of the Annual Register, we gave a historical view of the progress of the different sciences, from the first dawnings of philosophy to the present times. This view, though much shorter than we could have wished, was as extensive as consisted with our limits. Our object, at present, is to lay before our readers a view of the additions which have been made to the different sciences during the course of the year 1809-10. Though we shall confine ourselves as nearly as possible to that period, it will not be in our power to do so entirely; for we cannot always make a discovery intelligible to our readers, without laying before them the circumstances, or the train of investigation, that led to it, which may sometimes oblige us to go farther back than the period of which we professedly treat. We must warn our readers, too, that the present period is unfriendly to science of almost every description. The awful contest in which Europe is engaged has a tendency to withdraw the attention of men from the peaceful pursuits of science, and to fix them upon political considerations. The iron hand of despotism has crushed some of the finest regions of Europe, and banished from them even the

freedom of scientific investigation. Some of the most illustrious ornaments of the sciences on the continent have been reduced to abject poverty. Even in France, the country which has been the instrument employed in crushing the other nations of Europe, the trade and manufac tures have been nearly annihilated, and learning, as a necessary consequence, has been discouraged and has declined. Britain, favoured by its insular situation, by its naval superiority, and by the energy of its government, has hitherto escaped the storm which has laid waste almost every other part of Europe. It is in Britain, accordingly, that the greatest scientific discoveries have been made.

Whoever has paid any attention to the history of the sciences, must be aware that there are certain æras when the general attention of scien tific men is drawn to peculiar sciences almost exclusively. Thus, for example, during the greatest part of the seventeenth century, mathematics almost solely occupied the atten tion of scientific men. About the middle of the eighteenth century, electricity became the fashionable study, and every person of a liberal education was under the necessity of ma

king himself acquainted with that science. For some years past, che mistry has become the prominent object of investigation, and has, in some measure, supplanted the other sciences. It is in chemistry, therefore, that the greatest number of discoveries are to be expected: it occupies the fore-ground of the picture; we shall therefore commence our history with that science.

1. The most splendid discoveries in chemistry which have been made in modern times, owe their existence to an apparatus invented by Volta, an Italian philosopher of great eminence, and first described by him in the Philosophical Transactions for 1800. He found, that when plates of copper, plates of zinc, and wet cloths were piled above each other in regular order, placing the copper lowest, then the zinc, then the wet cloth, then copper again, then zinc, then the wet cloth, and always observing the same order till 40 or 50 pairs of the plates, with wet cloths between them, were raised into a pile, then if the finger of one hand be brought in contact with the bottom of the pile, and the finger of the other hand with the top of the pile, an electrical shock is felt at the instant of contact. If a wire be made to pass from the bottom to the top, so as to complete the circuit, a current of electricity passes through the pile, and continues to pass for a considerable time; this pile got the name of the Galvanic Pile, because some discoveries of Galvani gave birth to the investigations which led to the discovery of it. The galvanic apparatus soon underwent considerable improvements. Instead of the pile, Mr Cruickshanks substituted a trough of wood, into which each pair of plates, previously soldered together, was cemented.

Between each pair of plates there was a cell, these cells were filled with a liquid, and the trough was fit for action. Various liquids were used, but the most efficacious was found to be a very weak nitric acid. Very con siderable improvements were gradually introduced into the trough, both in the size and shape, and position of the plates. The latest and most approved form is this: The trough is made of stone-ware, and is divided into cells by diaphragms of stone-ware, about three quarters of an inch distant from each other. The plates are cut square, having a slip attached to the upper part of each, about an inch high, and thicker than the rest. These slips only are soldered together, so that there is a certain distance between the two plates at every part, except where they are soldered. Each pair is let down into the trough, so that there is a diaphragm of stoneware between the plates. The liquid is then poured in, and the trough is fit for action.

Almost all the discoveries in chemistry, which have resulted from the use of the galvanic trough, have been made in England. Messrs Nicholson and Carlisle discovered, that if a wire of platinum or gold be attached to the extremity of the trough at which the zinc plate is, (which we shall call the zinc end,) and a similar wire to the copper end, if these two wires be introduced into a glass of water, and placed within a small distance of each other, the water will be decomposed, the oxygen gas being separated from the wire attached to the zinc end, which is the positive end, and the hydrogen gas from the wire attached to the negative or copper end. By the subsequent experiments of Cruickshanks, Wollaston, Davy, &c. it was found that other substances

besides water, for example, nitric acid, sulphuric acid, ammonia, metal lic oxides, &c.—were decomposed by the same energy, and that the power of decomposing depended upon the size of the trough.

But Mr Davy is the person to whom we are indebted for the most important discoveries respecting the action of the galvanic trough. By a most ingenious and satisfactory set of experiments, he succeeded in demonstrating that galvanism has the property of decomposing all compound bodies, provided it be sufficiently strong, that oxygen and acids always separate at the wire in contact with the positive end of the trough, while hydrogen, alkalies, earths, and metals, accumulate round the negative pole. Galvanism then, or electricity, is capable of destroying chemical affinity, however powerful, and of producing repulsion and consequent separation between particles of matter, however intimately combined. From this curious and unex. pected law, Mr Davy drew, as an inference, that when bodies unite chemically, they are in opposite states of electricity, the one negative, the other positive; and that when they are brought to the same state they no longer remain united, but repel and immediately separate from each other. 2. It had long been the opinion of chemists, that the fixed alkalies are compounds, but all attempts to decompose them had entirely failed. It occurred to Mr Davy, that the galvanic battery, which he had found so powerful an instrument of decomposition, might be successfully used to separate the constituents of these bodies from each other. Various unsuccessful trials were made; at last he found that, when a piece of potash is left exposed to the air for an in

stant or two, it becomes sufficiently moist on the surface to conduct elec tricity. If, in this state, it be placed upon a disc of platinum, connected with the negative extremity of the galvanic trough, and a platinum wire from the positive extremity of the trough be made to touch it, gas is evolved, and small metallic globules, similar to globules of mercury, make their appearance. New experiments informed him, that the gas evolved was oxygen, and that the potash, by the galvanic energy, had been decomposed into oxygen and the metallic substance Óne hundred pair of plates of 6 inches square form a galvanic battery sufficiently powerful to decompose potash. Soda is likewise decomposed by the same means, but it requires a more powerful battery. Thus Mr Davy ascertained that potash and soda are metallic oxides. To the metals which constitute their basis he gave the names of potassium and sodium.

These bodies differ exceedingly from all the metals with which we were previously acquainted. By the galvanic battery, they could only be obtained in small globules; but Thenard and Guy Lussac, two French chemists, discovered a method of obtaining them in consider. able quantity. Into a bent gunbarrel, previously coated on the outside with clay, a quantity of iron turnings are introduced; the gunbarrel is then placed in a furnace in such a manner that the iron turnings can be raised to a very high temperature. To one end of the gun-barrel a bent glass tube is luted, containing some mercury, in order effectually to exclude the air. To the other extremity an iron stopper is ground, containing about two ounces of potash, previously exposed to a red

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