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you plough into the ground the crop which the ground has already nourished, what do you gain? The reply is, you gain the whole of the nutriment that the crop has acquired from the air, and from the decomposition of water: an amount of nutriment, probably, equal to one-fourth, at least, of what the plant can furnish by gradual decomposition. This brings us to the question, what parts of the plant does nature set to work to obtain nutriment and supply the growth?

First The Roots. There is no evidence whatever, that the roots of a plant can take in any solid matter, or any gaseous matter, unless previously dissolved in water. The sap of every tree and plant, whether ascending or descending, is a fluid; holding in solution more or less of the substances destined to become parts of the plant itself. How does this fluid ascend by means of the roots? Assuredly not by capillary attraction, which would stop at an inch or two; nor by any of Sir H. Davy's " physical agencies," which are utterly worthless to account for the phenomenon. Our mode of explaining it, is as follows: a drop of fluid, containing nutriment, comes in contact with a root fibre in search of nutriment. The mouth of the fibre, that is, the internal sides of the tube, become stimulated; they contract on the drop of fluid, and by a contraction à tergo, propel it upwards, where another part of the containing tube being stimulated in like manner, contracts in like manner, and the drop is thus propelled to the very top of its course, in consequence of the irritability of the living fibres of the containing vessels.* In its course, it undergoes the processes necessary to form it into the nutriment, and assimilate it to the substance of the plant. This is done by means of the peculiar organization of each plant, acting as the nature of the plant requires.

Were we to propose a theory, it should be, that the organization of vegetables and animals, includes and arranges a series of galvanic batteries; by means whereof, decompositions and recompositions are effected in organized bodies, which the chemistry of the laboratory cannot explain. We strongly suspect, that when two dissimilar bodies come in contact, electrical effects, chemical effects, and caloric, more or less, are always produced: whenever two dissimilar bodies, with an intervening conducting fluid, capable of acting upon one of them, come together, galvanic effects are produced. And these arrangements are certainly found in every living vegetable and animal. But the view we can as yet take, is not clear: we see as yet through a glass darkly; and, to use the language of the Poet, "the present affords but a glimpse through the gloom." However, discoveries are in progress, and in this, as in every other respect, we may cheeringly say of the march of mind, Ca Ira.

* We are aware of the theory of Monsieur Dutrochet in his late book, "L'Agent immediat du mouvement vital dévoilé dans sa nature, et dans sa mode d'action, ches les végétaux et chez les animaux."-8vo. Paris, 1826. M. Dutrochet is of opinion that the lymphatic tubes through which the sap ascends, are incontractile; but for no valid reason in support of this doubt that we can discover. If the vegetable fibre be possessed of vegetable life, it must be contractile; this being the characteristic property of living fibre. Nor can his obscure explanation by endosmose and exosmose be satisfactorily admitted, without admitting the contractile property of the cells and membranes introduced in his explanation; nor does the application of galvanism in the experiment of M. Porret, or in that of M. Dutrochet, negative the contractility of the living fibre-especially as those experiments did not succced with inorganic substances.

During the decompositions of the sap, the observations of GayLussac and Thenard, which we see nothing to controvert, will apply. Whenever hydrogen and oxygen unite in a vegetable, so that the oxygen is to the hydrogen in a greater proportion than is found in water, the result is an acid. Whenever they unite in the same proportions that form water, the produce is saccharine, or mucilaginous, or fecula, or woody fibre. Whenever they unite so that the oxygen is in a less proportion than in water, we have resins, oils, gum-resins, caoutchouc, &c. In these cases, carbon forms the third ingredient.

In Pine and Fir trees, there seems no doubt but water itself is decomposed, and oxygen is given out, during the formation of pitch, turpentine, &c. Is the common prejudice, so prevalent in South-Carolina, in favour of a summer's residence in the pine-woods, confirmed by this explanation? It seems so to us.

So much for the function of the roots. But the leaves also play their part in the business of nutriment. The experiments of Priestly, Ingenhouz, Sennebier, and Woodhouse of Philadelphia, have established the fact, beyond all doubt, that the carbonic acid of the atmosphere, is decomposed by the leaves of a plant, when the leaves are stimulated into action by the light of the sun. This, we suspect, is one of the great sources of the supply of carbon; and of course, a crop ploughed in, adds to the soil as so much gain, all that the leaves have acquired from the atmosphere. But this addition of carbon, induces also from the roots, a greater supply of hydrogen and of oxygen; which would not have been needed, had not this additional carbon been procured by the industry of the leaves. The theory of manure, therefore, by means of crops ploughed in, while in early flower, is supported by all the considerations above suggested.

Such are the observations we have thought it worth the while of our readers to consider on the leading points of practical and theoretical Agriculture. Let no one turn aside contemptuously

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from theory; for, until the theory of the art be well established and generally understood, the practice will be desultory, empirical, and unintelligible. It is to the enlightened part of our community that we are to look for useful explanations, and permanent improvements in the practice of this first of arts. suggestions of this paper, therefore, are addressed to the wellinformed class of our readers, in hopes of exciting attention and reflection among those of our citizens, who are most capable of adding to the common fund of useful knowledge.

ART. III.-1. The Campaign of 1781, in the Carolinas; with Remarks, Historical and Critical, on Johnson's Life of Greene, &c. By H. LEE. Philadelphia. 1824.

2. Letter of the Earl of Moira (formerly Lord Rawdon) to General Henry Lee, in relation to the Execution of Colonel Isaac Hayne. Written, 1813: Published, 1824.

THE work which stands at the head of this Article, is one of those controversial publications which owes its existence to Johnson's "Sketches of the Life of Greene." It is written by Henry Lee, of Virginia, son of the late General Henry Lee, who states, that he wishes it to be regarded merely as "the effort of a son to defend the memory of his father. It is not our purpose, however, to enter into the merits of the controversy between the author of the "Sketches," and of the "Campaign of 1781." We do not propose to become umpires between these literary combatants, but merely to call the attention of our readers to an incident in our revolutionary history, which is alluded to in the work before us, and which produced the letter of the Earl of Moira. We mean, THE EXECUTION of ColoneL ISAAC HAYNE.

Perhaps, no event involving the fate of an individual, ever excited deeper interest in the public mind than that execution. From one end of the continent to the other, the transaction filled every bosom with indignation, and threatened to give to the war a darker and more melancholy character. Every circumstance connected with it was fully canvassed, every minute detail was eagerly listened to, and public opinion, at least, in this country, finally settled down into a conviction, that a more barbarous and useless sacrifice of the life of an innocent and estimable man, never disgraced any age or any country. Nor was this sentiment confined to those who had taken part with the Americans in the great struggle :-We have the authority of eye and ear witnesses of the fact, that the excitement in Charleston, (then a Royal garrison) among the adherents of the British Government, was deep and profound, and the expression of their regret and condemnation by no means stifled. Even in England, the fate of Colonel Hayne, created an interest scarcely inferior to that produced by the death of André. The merits of the proceeding were discussed by the press, and within the walls of Parliament, with a boldness and freedom, which shewed, that however it might be in the power of the Ministry to prevent an official inquiry into the subject, they could not prevent the formation and expression of opinions extremely unfavorable to the conduct of the Royal commanders in South-Carolina. It is not to be supposed, that under these circumstances, any justification or apology that could have been offered for the act, was omitted. The public attention both in Great Britain and this country was too much roused, the reputation of Lord Rawdon and Colonel Balfour too deeply involved in the inquiry, to permit them to remain indifferent, or to omit to offer any defence of which the act was susceptible. Accordingly, we find that the grounds on which they pretended to justify their conduct were immediately after the execution of Colonel Hayne, explicitly stated and publicly avowed, and every thing they had to urge in their defence was submitted to the judgment of the world. Public opinion was formed on these full and authentic materials, and when the transaction came finally to be recorded in the histories of the day, the proceedings, documents and arguments in relation to it, were all referred to, as the basis of the judgment which the impartial historian felt himself compelled to pronounce. We venture to say, that if there be a single event connected with our revolutionary history, on which a fixed and settled opinion has been entertained by all classes of men, it is, that the execution of Colonel Hayne was an illegal and barbarous act of vengeance, executed by Lord Rawdon and Colonel Balfour, without even the shadow of excuse or apologyand, that this opinion rested not on the prejudices and passions

of the day-not on loose rumours or doubtful allegations-but on well authenticated, notorious and admitted facts. Under these circumstances, it was certainly calculated to excite no little astonishment, that an attempt should have been made upwards of thirty years after the transaction occurred, and when almost all the contemporaries of the parties had been "gathered to their fathers," to give an entirely new aspect to the affair.The author of the "Campaign of 1781," attempts to excuse the course he has pursued in publishing the letter of the Earl of Moira, by suggesting, that "it will afford a fair opportunity to such of his (Colonel Hayne's) surviving friends, as may be best acquainted with the facts, to give a definite and categorical refutation of whatever incorrect opinions or inaccurate statements it may contain, and to satisfy, not their countrymen, but the world, that the doom of this lamented patriot was as unmerited, as the fortitude with which he met it, was touching and heroic."

But it does appear to us, that in publishing the letter of Lord Moira, (if there was any propriety in publishing it at all) Mr. Lee would have done but a simple act of justice to the memory of Colonel Hayne, and we think to the reputation of his own Father, if he had turned to the histories of the day, and demonstrated from them, that the facts of the case afford no support for the apology now offered by one of the perpetrators of the deed. If he had taken this course, one of the most interesting events in our history would not have been subjected to suspicion, the memory of one of the most distinguished of our martyrs, would not, even for a moment, have been sullied by the breath of calumny, and we should have been saved the trouble of exposing the misrepresentations of the Earl of Moira.

The author of the "Campaign of 1781," speaks of the letter of the Noble Earl, as distinguished for "its calm and elevated tone, its lucid and modest sratements, its mild sensibility and noble moderation," and expresses his regret "that the liberal and enlightened were induced to entertain opinions so injurious to the character of its author." "It is plain (adds Mr. Lee) from this document, that many of the circumstances previous to the Execution have been misunderstood in this country; and, that in so far as the resentment and abhorrence which the calamity occasioned, received aggravation from them, it was unfounded;"and he concludes by charging Judge Johnson with "re-echoing, amplifying and distorting the prevailing misapprehensions regarding it." Now, we regret extremely that we are not informed, which are "the many circumstances," connected with the execution of Colonel Hayne, that have been "misunderstood

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