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to the Edinburgh Review. It is im- are parents or guardians to postpone possible in this place to do any jus- his immediate advantage to any betice to the argument; but the pre- nefits that may arise to future ages ceding extract may possibly be of from contributing their individual assome use in directing the attention of sistance in the production of two or our Scottish readers to a view of the three professors of splendid talents to subject, which they are not much ac- adorn the history of science, and becustomed to consider.
stow a temporary celebrity on the The celebrity of some systems of scene of their labours ? If there be education exclusively carried on by any truth in the position, that to propublic lectures, has been traced to the mote the boundaries of human knowlocal and peculiar attractions which ledge, and to cultivate the minds of the professorships possess for men of youth, are occupations totally disfirst-rate talents and acquirements, tinct from each other, and not unfreand the inducements which the dis- quently at variance, it must be adchargeoftheir official duties affords for mitted to be a great error and a gross the continualexertion of their powers: delusion to confound the fame of pubAnd if the principal object of a uni- lic professors in the literary world versity were the advancement of learn. with the merits of a system of eduing and science, and not the instruc- cation with which they happen to be tion of youth, those systems might connected. be allowed to claim the preference We have endeavoured to render which sacrifice the latter to the for- this account of the studies pursued mer; but if universities have been at Oxford as impartial as possible ; instituted for the pupils, and not for and have taken care not to confound the professors, the young men who what is efficient with what is nominal: frequent them for the cultivation of we fear, however, that it is in some their minds, have a right to complain, measure imperfect, as our limits will if their interests are in any instance not permit us to enlarge on the va. neglected, though the whole world rious important topics which have besides should reap incalculable bene. hastily passed before us in the course fit from the labours of their teachers. of the preceding observations. We It has been stated by Doctor Adam had intended to conclude with some Smith and other writers, that the edu- notice of the arguments by which the cation which is most likely to pro- authors quoted above have defended duce a man of solid learning and the importance which is attached to knowledge, is to impose upon him classical learning at Oxford; but we the necessity of teaching others, and, have not room for the ample consideabove all, to oblige him to teach by ration which they demand, and we compositions of his own and in pub. cannot hope to say any thing very lic; and it is an undoubted fact, that new or interesting in this place on a a large proportion of the most valua- subject on which so much has been ble acquisitions in literature and already written. One opinion is imscience have in all ages been made by plied in what has been said above, those whose talents were called into that, even admitting classical studies exertion by the instruction of youth. to possess all the merits for which But when the question is, to what their fondest advocates contend, one university a young man is to be sent, year may be profitably subtracted from the time now employed in pre. this system are too dearly purchased paration for the public examinations, by the neglect or exclusion of the and devoted to the study of natural sciences already mentioned during a and moral philosophy and political period of time so inconsistent with economy. It cannot be disputed the shortness of human life. Were that the present system is calculated the alteration made which we have vento produce habits of accurate inves- tured to suggest, there cannot be a tigation, and laborious exertion, to- doubt that Oxford would soon aftally unknown in those seminaries ford the model of a system of public where education is carried on by the education far more perfeo# than any popular mode of public lectures ; of which the world can at present though we are inclined to think that boast. these and all the other advantages of
REVIEW OF SCIENCE.
In the last volume of the Annual freedom of scientific investigation. Register, we gave a historical view Some of the most illustrious ornaof the progress of the different scien- ments of the sciences on the contices, from the first dawnings of phi- nent have been reduced to abject polosophy to the present times. This verty. Even in France, the country view, though much shorter than we which has been the instrument emcould have wished, was as extensive ployed in crushing the other nations as consisted with our limits. Our ob- of Europe, the trade and manufac. ject, at present, is to lay before our tures have been nearly annihilated, readers a view of the additions which and learning, as a necessary conse. have been made to the different sci- quence, has been discouraged and ences during the course of the year has declined. Britain, favoured by 1809-10. Though we shall confineour. its insular situation, by its naval suselves as nearly as possible to that pe periority, and by the energy of its riod, it will not be in our power to government, has hitherto escaped the do so entirely; for we cannot al. storm which has laid waste almost ways make a discovery intelligible to every other part of Europe. It is our readers, without laying before in Britain, accordingly, that the them the circumstances, or the train greatest scientific discoveries have of investigation, that led to it, which been made. may sometimes oblige us to go
far- Whoever has paid any attention to ther back than the period of which the history of the sciences, must be we professedly treat.
aware that there are certain æras warn our readers, too, that the pre- when the general attention of scien. sent period is unfriendly to science of tific men is drawn to peculiar scienalmost every description. The aw- ces almost exclusively. Thus, for ful contest in which Europe is enga- example, during the greatest part of ged has a tendency to withdraw the the seventeenth century, mathemaattention of men from the peaceful tics almost solely occupied the atten. pursuits of science, and to fix them tion of scientific men. About the upon political considerations. The middle of the eighteenth century, iron hand of despotism has crushed electricity became the fashionable stu. some of the finest regions of Europe, dy, and every person of a liberal edu. and banished from them even the cation was under the necessity of ma
king himself acquainted with that Between each pair of plates there was science. For some years past, che- a cell, these cells were filled with a li. mistry has become the prominent ob- quid, and the trough was fit for acject of investigation, and has, in tion. Various liquids were used, but some measure, supplanted the other the most efficacious was found to be sciences. It is in chemistry, there a very weak nitric acid. Very confore, that the greatest number of dis- siderable improvements were gradual. coveries are to be expected : it occu- ly introduced into the trough, both pies the fore-ground of the picture ; in the size and shape, and position of we shall therefore commence our his. the plates. The latest
and most aptory with that science.
proved form is this : The trough is 1. The most splendid discoveries made of stone-ware, and is divided inin chemistry which have been made to cells by diaphragms of stone-ware, in modern times, owe their existence about three quarters of an inch disto an apparatus invented by Volta, tant from each other. The plates an Italian philosopher of great emi- are cut square, having a slip attached nence, and first described by him in to the upper part of each, about an the Philosophical Transactions for inch high, and thicker than the rest. 1800. He found, that when plates These slips only are soldered togeof copper, plates of zinc, and wet ther, so that there is a certain distance cloths were piled above each other in between the two plates at every part, regular order, placing the copper low- except where they are soldered. est
, then the zinc, then the wet cloth, Each pair is let down into the trough, then copper again, then zinc, then so that there is a diaphragm of stonethe wet cloth, and always observing ware between the plates. The lithe same order till 40 or 50 pairs of quid is then poured in, and the the plates, with wet cloths between trough is fit for action. them, were raised into a pile, then if Almost all the discoveries in che, the finger of one hand be brought in mistry, which have resulted from the
contact with the bottom of the pile, use of the galvanic trough, have . and the finger of the other hand with been made in England. Messrs Ni
the top of the pile, an electrical shock cholson and Carlisle discovered, that is felt at the instant of contact. If if a wire of platinum or gold be at. a wire be made to pass from the bot- tached to the extremity of the trough tom to the top, so as to complete at which the zinc plate is, (which we the circuit, a current of electricity shall call the zinc end,) and a similar passes through the pile, and conti. wire to the copper end, if these two nues to pass for a considerable time; wires be introduced into a glass of wa. this pile got the name of the Galva- ter, and placed within a small distance nic Pile, because some discoveries of of each other, the water will be decomGalvani gave birth to the investiga- posed, the oxygen gas being separated tions which led to the discovery of it. from the wire attached to the zinc The galvanic apparatus soon under- end, which is the positive end, and went considerable improvements. In the hydrogen gas from the wire atstead of the pile, Mr Cruickshanks tached to the negative or copper end. substituted a trough of wood, into By the subsequent experiments of which each pair of plates, previous- Cruickshanks, Wollaston, Davy, &c. ly soldered together, was cemented. it was found that other substances besides water,-for example, nitric a- stant or two, it becomes sufficiently cid, sulphuric acid, ammonia, metal. moist on the surface to conduct elec. lic oxides, &c.—were decomposed by tricity. If, in this state, it be placed the same energy, and that the power upon a disc of platinum, connected of decomposing depended upon the with the negative extremity of the size of the trough.
galvanic trough, and a platinum wire But Mr Davy is the person to from the positive extremity of the whom we are indebted for the most trough be made to touch it, gas is important discoveries respecting the evolved, and small metallic globules, action of the galvanic trough. By similar to globules of mercury, make a most ingenious and satisfactory set their appearance. New experiments of experiments, he succeeded in de informed him, that the gas evolved monstrating that galvanism has the was oxygen, and that the potash, by property of decomposing all com- the galvanic energy, had been decompound bodies, provided it be suffi. posed into oxygen and the metallic ciently strong, that oxygen and acids substances One hundred pair of always separate at the wire in con- plates of 6 inches square form a galtact with the positive end of the vanic battery sufficiently powerful trough, while hydrogen, alkalies, to decompose potash. Soda is likeearths, and metals, accumulate round wise decomposed by the same means, the negative pole. Galvanism then, but it requires a more powerful bat, or electricity, is capable of destroying tery. Thus Mr Davy ascertained chemical affinity, however powerful, that potash and soda' are metallic and of producing repulsion and con- oxides. To the metals which constisequent separation between particles tute their basis he gave the names of of matter, however intimately com- potassium and sodium. bined. From this curious and unex. These bodies differ exceedingly pected law, Mr Davy drew, as an in- from all the metals with which we ference, that when bodies unite che- were previously acquainted. By the mically, they are in opposite states of galvanic battery, they could only be electricity, the one negative, the obtained in small globules ; but other positive ; and that when they Thenard and Guy Lussac, two are brought to the same state they French chemists, discovered a meno longer remain united, but repel and thod of obtaining them in consider, immediately separate from each other. able quantity. Into a bent gun
2. It had long been the opinion of barrel, previously coated on the outchemists, that the fixed alkalies are side with clay, a quantity of iron compounds, but all attempts to de- turnings are introduced; the guncompose them had entirely failed. It barrel is then placed in a furnace in occurred to Mr Davy, that the gal- 'such a manner that the iron turnings vanic battery, which he had found so can be raised to a very high temperapowerful an instrument of decompo- ture. To one end of the gun-barrel sition, might be successfully used to a bent glass tube is luted, containing separate the constituents of these bọ. some mercury, in order effectually to dies from each other. Various un- exclude the air. To the other exsuccessful trials were made ; at last tremity an iron stopper is ground, he found that, when a piece of potash containing about two ounces of pot. is left exposed to the air for an in. ash, previously exposed to a red