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Ampère, in his first trials, failed in his endeavours to render it sensible; but on persevering in the attempt, his success, at last, was complete and unequivocal.
It will be seen that the theory of Ampère has the advantage of explaining many anomalous appearances in the induction of magnetism, much more readily than any other; as, for instance, the occasional co-existence of south poles at each end of a magnetic bar, and of a single north pole at the centre. It explains very simply and naturally the consequences observed on the fracture of a magnet; for the opposite polarities are supposed to arise from the same currents, and only take place on the different sides of those currents. It also assigns a reason for various practical rules which are to be observed in making artificial magnets, and of which no other theory could furnish an explanation. It accounts satisfactorily for the want of success in all the attempts which have been made to obtain any of the ordinary electrical or galvanic effects, from whatever form or combination of magnets has yet been devised, and teaches us why no such effects are to be expected.
It may be urged as an objection to Ampère's theory, that the assumption on which it is founded-namely, the perpetual circulation of electric currents among the particles of magnetic iron, is hypothetical in the extreme, and violates every analogy and semblance of probability. But to this it may be answered, that the facts to be explained are themselves so much at variance with all the known laws of ordinary corpuscular action, that they necessarily imply the operation of agents which are governed by laws peculiar to themselves. That hypothesis deserves the preference, which, while it is itself most simple, is also most comprehensive in its applications; which unites together the greatest number and variety of facts;-which leads to the discovery of new facts, and suggests the invention of new combinations, and which perfectly accords with all the observed results. Another criterion of a true theory, is its capability of furnishing elements of analytical investigation, by which the numerical relations may be determined that connect together facts, in their nature apparently remote and disjoined.
In all these respects it will be found, that no theory of electromagnetism hitherto devised can at all enter into competition with that of Ampère. It is impossible to deny that a great advance will have been made in the philosophy of nature, if it can be shown, or even rendered probable, that all the phenomena usually referred to the operation of magnetism, as a principle totally distinct from electricity, are mere electrical effects; that the former is, in fact, included in the latter; and that, instead of two agencies, there exists but one.
It must, however, be confessed, that much still remains to be done before the theory can be regarded as satisfactorily established. The new discoveries which are continually making in electro-magnetic science will subject it to a severe ordeal, and must soon either give it decisive confirmation, or produce its complete overthrow. The curious facts lately brought to light by Arago, Barlow, Christie, Babbage, and Herschel, relative to the magnetic effects induced on iron, and the magnetism manifested by other metals, during their rotation, are yet to be explained consistently with Ampère's theory. The recent discovery of the influence of the solar rays in inducing permanent magnetism on iron, under certain circumstances, a fact announced by Morichini, and now completely established by the ingenious and successful experiments of Mrs. Somerville,* indicates the existence of some hitherto unsuspected connexion between magnetism and light, and cannot fail eventually to extend our knowledge in this highly interesting department of natural philosophy.
ART. XI.-1. Report on the Trade in Corn, and on the Agriculture of the North of Europe. By W. Jacob, Esq. (Printed by order of the House of Commons.) London. 1826. 2. A Letter to the Electors of Bridgenorth, upon the Corn Laws. By W. W. Whitmore, Esq., M.P. Edinburgh. 1826.
N the observations which we feel it necessary to make on the subject of the expected alteration in the corn-laws, we shall abstain from offering any remarks in detail upon the practical modifications in them, which we might think it expedient to be suggested; because we are content to leave their arrangement in the hands of the government, whose position of neutrality between what are called (as we think, erroneously) the conflicting interests of agriculturists and manufacturers, enables them to suggest a change with unimpeached impartiality, and whose sources of information supply them with the most adequate means of executing such change, with due consideration for the interests of all parties, separately or collectively.
The leading principle of the changes effected by the late parliament in our commercial policy was founded in the substitution of a free importation, subject to adequate protecting duties, instead of a system of absolute prohibition. We are surprised to find that there are so many persons both of the agricultural and manufacturing classes who are disposed to
See Philosophical Transactions for 1826, p. 132.
protest against this change of policy. For in what does it consist ?-in protection to the home-producer, whether of corn or manufactured goods, though not to the extent of forming a monopoly, which has only the effect of stimulating production beyond safe limits, and of throwing on the consumers the pressure of maintaining and supporting that unnatural stimulus. Wherever prohibition exists with respect to manufactured articles, illicit importation-smuggling-must exist in a proportionate degree. Under such a system, it is not only the revenue that suffers,it is not only the morals of those parties who are directly tempted by law to outrage the law that suffer-but the morals of all classes of the community;--for how few are not accustomed to reconcile it to themselves to encourage acts of spoliation punishable by law, through the purchase of articles surreptitiously introduced; and to imagine that they make a sufficient apology, when they state that the articles in question are not to be obtained in any other manner! The whole of the measures of government with respect to the changes of our commercial law will be found to be based on these simple principles; principles in themselves not only defensible, but utterly unassailable, and which are obtaining, and will obtain, signal triumph over their adversaries.
There are persons belonging to the agricultural interest who say very little on this subject of free trade in manufactures, but protest, in the most loud and unmeasured terms, against any change whatever being made in the present corn-laws, and inculpate the government for their presumption in entertaining even the question of modification. Does the agriculturist of this class ever recollect the time when his commodity sold for an infinitely lower rate in the market than it now obtains, when taken with a ratio to the taxes then paid by him--and this even making full allowance for the possible effect of the fluctuations of currency upon prices? Does it ever suggest itself to him, that, in proportion as the manufacturing population of this country increased, a greater demand existed for his peculiar production, and that he has literally to thank the existence of that population for his rents and his advantages? Does he suppose that he has sold his commodity abroad? The answer must be-Certainly not: it is notorious that there has not been any exportation of corn. Does he suppose that the non-manufacturing part of the community is in the habit of consuming such an extra degree of produce as to have occasioned that increased demand which has raised his commodity in the market? He cannot entertain such an opinion. He must, then, be compelled to admit that it is the manufacturing part of the population which has swelled his rents and made him what he is. And how have his rents been increased?
Is there any mystery in the process? Does he not know that, if the demand for corn is greater than the supply, more corn will be grown? Does he not know that lands of the first class of fertility will be first occupied ?-that, as the production of corn progressively increases, inferior lands must be brought into cultivation? If brought into cultivation, does he not know that they must, ex vi termini, repay, with the ordinary profits of stock, the expense incurred in their cultivation? Does he not know that his own tenant, occupying land of a superior quality, is only led to expect to make the same profits which a man cultivating land of an inferior quality is found to make? Does he not know that the difference of the money-price of the produce raised by these two parties is, in the present circumstances of this country, the measure of his rent? Does he not know that, consequently, every succeeding inferior quality of land brought into cultivation has the effect of increasing his rent,-not (as is frequently but most invidiously contended) through any tricks of combination on the part of the landlords as a body, but by the inevitable course of things, arising out of the relations of property subsisting between the proprietor of land and the proprietor of capital employed upon land? Does he not perceive now the puerile imbecility of those meetings in Norfolk, which were holden at the period of the highest prices, when libations in claret were offered up to the tutelary genius of England, under whose patronage corn was found to grow where it had been said that a rabbit could not find a blade of grass to conceal itself from its natural enemies? What, when analysed, was the history of all this extraordinary prosperity? Why, simply, that the consumer was called upon to pay a price which would remunerate the capitalist for raising wheat on these rabbit-warrens, and which, in its re-action, had the effect of raising the rent of every acre of land of superior quality throughout the United Kingdom.
What then is the moral of this reasoning? That the agriculturist should not be protected, and adequately protected, and permanently protected? The minister who should act upon such principles would abandon his most sacred duty. But is there no protection short of monopoly?
The agriculturists of these islands should be careful, and consider well what they are about at this crisis. Do they, seriously weighing all the circumstances of the case, think it possible that, if the price of corn be sustained in this country at a preposterous height, our present manufacturers can continue to sell their produce to foreign states? Undoubtedly, reasoning selfishly, if the agriculturists could secure these two conflicting alternatives-high prices
of corn at home, in consequence of the existence of a large manu facturing population, and the maintenance of that manufacturing population in full employment, under the circumstance of high prices, they would be insane not to endeavour to accomplish measures that would secure the high price of corn; but even under that supposition, they must be told that their present corn-laws would not execute their purpose. These alternatives, however, are notoriously incompatible. If the price of corn be to be maintained to suit the exclusive purpose and pocket of the agriculturist, foreign countries, where not only the necessaries of life are cheaper than in England, but the scale of comfort is lower also, will be able, at no distant period, to undersell the manufacturers of this country; and can the agriculturist contemplate with satisfaction that period, when his own thirst for present profit will have greatly diminished the comforts of the very population whose power to purchase gives the value to his own production? What, then, does common sense or common instinct dictate? What else, but that proportions should be preserved,—that a perpetual demand should be secured for agricultural produce, by allowing the importation of foreign corn so far to operate upon price in this country, as to enable the manufacturer to maintain, at least, if not to increase, his transactions with the civilised world, as a seller of those commodities which the different nations of the world, his customers, are prepared to buy? and we have to add, that to endeavour to strike out that mean, which is here shadowed in theory, is the duty of the government of the country, and a duty from which, it is to be hoped, they will not be induced to flinch under any conceivable combination of circumstances.
But are the present corn-laws calculated to secure the present purpose of the agriculturists, or, we should rather say, of one particular sect of our agriculturists? So far from it, that the government of the country have been compelled, in more than one instance, to recommend a direct violation of the existing law, from an unwillingness to expose the community to the consequences of a strict maintenance of that law. And a noble sort of legislation for a great country must that be, which constantly requires the screw of the executive, to extend or contract it as circumstances may make necessary! It would be precisely as rational to allow the executive to settle the standard of currency, from period to period, at their own will and pleasure. Although we may give government credit for the purest and best motives, and for the soundest discretion, yet if they are permanently to exercise the duty of admitting foreign corn contrary to law, there is not a transaction in the country, from one end to the other, which can fail to be more or less affected (pecuniarily