humidity through its entire mass, is, we believe, permeable to elastic fluids, and altogether incapable of completely excluding or confining them. Animal membrane, even in the comparatively thick and dense state, for example, of a bladder is sufficiently known to be permeable to gases; and we see no force in the distinction, with regard to this effect, between the living and dead solid, since it is a property connected with mere mechanical structure and the influence of humidity, of the suspension of which, by the presence of life, we see no proof. We consider the blood, therefore, in circulating through the very minute vessels, and over the very extensive surface of the lungs, as exposed to the action of the air, nearly as freely as if the delicate membrane confining it were not interposed; especially as the passage of the air through that membrane, and its consequent approximation to the blood, must be aided by the degree of compression which it suffers in the air cells from the force exerted in inspiration; the oxygen of that air having an affinity with the carbon of the blood, will in this approximation combine with it, and form carbonic acid; and when, in the alternating abatement of that compression, expiration begins to take place, the carbonic acid, formed as we have just stated, will be disengaged, and become elastic. We agree, therefore, with Mr. Ellis, in rejecting the hypothesis, that the oxygen gas is absorbed by the blood, carried by it through the whole course of the circulation, and converted into carbonic acid, which is discharged from the venous blood when it passes through the lungs. But we see no difficulty in the supposition that the oxygen of the air may, as above explained, act on the blood in the lungs and combine with its carbon, and that the carbonic acid formed by this combination may be immediately discharged in its elastic form.

Lastly, we would remark, that the transmission of elastic fluids through the coats of the blood vessels in the lungs appears to us to be established by the effects which arise from the inspiration of various gases. By some, it is known, that death is induced more speedily than happens from the mere deprivation of oxygen, and the irritability of the heart is found to be even completely destroyed by them, effects which we do not think admit of an adequate explanation from any supposed action of these gases on the nerves of the lungs, but which must be ascribed to their action by the medium of the blood. The exhilarating effects from the inspiration of nitrous oxide gas appear to us a proof not less conclusive, which we cannot consider as much weakened by our author's observations, with regard to the uncertainty in the production of this effect, or to

effects somewhat similar being produced by the inspiration of some other gases.

On the whole, therefore, we should be disposed still to maintain the opinion, that the oxygen of the air acts chemically on the blood in the lungs, and that probably the most important final purpose of respiration is, by this action, to produce the necessary changes in the composition of the blood.

Mr. Ellis, we think, is successful in contending that in respiration there is no consumption of oxygen gas, beyond what is necessary to the formation of the carbonic acid expired, that there is none therefore absorbed by the blood so as to be retained: the apparent consumption of oxygen beyond this, when respiration is performed under circumstances which render it laborious, is probably owing, as he remarks, to the respiratory organs being unable to effect so complete an expulsion of the air as in natural respiration. He has also examined the experiments, whence it was inferred, that there is a consumption of nitrogen gas in respiration, as well as some others more recently brought forward, as proving an evolution of this gas from the blood under peculiar circumstances of respiration. We consider the conclusion for which he contends as sufficiently established that there is neither an absorption nor an evolution. That there is no absorption had been shewn by the accurate experiments of Allen and Pepys: the evolution which other experiments by these chemists appeared to prove, Mr. Ellis regards as a fallacy, arising from the operation of the residual air of the lungs; and he gives a very ingenious explanation of the fact, apparently inconsistent with this hypothesis, that in those experiments in which the evolution of nitrogen was supposed to take place, the air expired exceeded even in volume the capacity of the lungs. This he supposes to arise from the circumstance, that the air, instead of being expanded, is actually condensed by its reception into the cells of the lungs, a condensation that may arise either from a contraction of these cells, or more probably, as Mr. Ellis supposes, from the influence of that attraction or adhesion exerted between air and the surfaces of bodies, which gives rise to its condensation in other cases where it is received into the interstices of porous bodies; of which effect charcoal, in its operation on elastic fluids, affords a striking example. The influence of this condensation, which has not been before attended to, may further be important in the production of some of the effects of respiration; it may facilitate the combination of the oxygen and carbon in the lungs; and it serves to account for those variations which happen in the relative volumes of inspired and expired air, and of the oxygen and

nitrogen of that air, when natural respiration is disturbed by causes which induce a preternatural exertion of the respiratory organs.

We must now conclude our account of this work, and we cannot do so without expressing our sense of the importance of the researches it presents, and the ability with which they have been conducted. Its details throw new light, and open fresh analogies, calculated to elucidate the grandeur and uniformity of the great Creator's works; and it may serve as a valuable link in that long chain of discovery which has been reserved for the present day; and of which we hope to give some account in our next number. Nor can we withhold our approbation of the candour and liberality which distinguish Mr. Ellis's work. We have differed in some points from the author, but this lessens not our respect for his talents, nor our confidence that important results may be obtained from his further pursuit of this investigation. His plan leads him to the consideration of the effects which arise from the introduction into the vegetable and animal systems, of the caloric set free from the combination of oxygen with carbon; he intimates some intention of prosecuting this subject, and we trust that he will find, in the reception of the present volume, sufficient inducement to carry this intention into execution.

ART. VII. Memoirs of the Honourable Thomas Jefferson, Secretary of State, Vice President and President of the United States of America; containing a concise History of those States, from the Acknowledgment of their Independence. With a View of the Rise and Progress of French Influence and French Principles in that Country. Two vols. octavo, New York, 1809.

In the first number of the British Review, we had (we can hardly

say) the satisfaction of laying before our readers a detailed statement of the facilities which the French party in America have found in the principles of its constitution, for the prosecution of their schemes against the British connection, and the prosperity of their own country. Every thing which we have since seen, and read, and heard upon the subject, has tended to fortify in our minds the justness of the conclusions then drawn, and to convince us, that unless a radical change take place in the American system of politics, a crisis must at length arise in this in

teresting country, that must either dissolve the Federal Union, or lead to such an improvement of its constitution, as will allow of a steady and rational system of government. We are far, however, from imputing generally to the leaders of the French party in the United States a sordid view of sacrificing what they think to be the real interests of their country, to private considerations of profit and ambition;-we believe them to be more frequently dupes than traitors; and that the French agents have succeeded in persuading them, that the commercial advantages, springing from friendly intercourse with England, and which French connection must oblige them to forego, are the result of a false view of policy in their actual state of society. They have been taught to believe, that their country will advance faster in the career of wealth and substantial power, by turning all the energies of its population to the improvement of its extensive territory, leaving the products to be exported in the ships of the commercial nations of Europe, and confining its own exertions to the mere defence of its coasts from insult. We must in particular do Mr. Jefferson the justice to observe, that during his first residence in Paris, M. Turgot and the economists were in the zenith of their credit; and that a man of Mr. Jefferson's character and confined abilities was very likely to become the sincere dupe of their plausible theories, and to believe that he would do his country good service, by making it the subject of a practical experiment of their truth.

The Americans have also been taught to believe, that the naval power of Great Britain is the only obstacle to the establishment of an universal and permanent freedom of navigation in time of war; a claim which Great Britain has steadily and uniformly opposed, while almost every other power of Europe has at some time or other, from motives of temporary and delusive policy, acceded to it. And the Americans, although dupes to this fallacious expectation, have sagacity enough to perceive, that they would almost solely reap the advantages of the freedom of navigation, were the European powers to carry it into effect. Experience might, indeed, have taught the Americans, (and has certainly taught the wisest of them), not to put too much confidence in such a system of immunity, since the powers which were most strenuous in its support have never failed to trench upon its privileges whenever they were found inconvenient.

The Americans, under sufferance of the British fleets, might possess the carrying trade of France from all quarters of the world, while Britain carries for herself; and this may be one cause of their partiality to France. But do they suppose, if

the British fleet were out of the way, or, as the French express it, the liberty of the seas were established, that. France would permit them for one year to continue the same carrying trade? Let them coolly answer this question, and they will then clearly perceive that the advantages held out by France must escape their grasp, from the instant when the destruction or dereliction of the British supremacy at sea has, in their opinion, placed them within reach. They are, therefore, contending for a shadow, which neither the destruction or preservation of the British supremacy can enable them to realize in substance.

But, abstractedly speaking, it must be confessed that their view of territorial policy (if we may so call it) is really plausible; although we do not quite perceive what France, possessing no commercial navy, would gain by the change, beyond that of substituting one species of tie to the English connexion for another. Whether America carries on her trade, or trusts for the sale of the raw products of her territory to the commercial navies of Europe, the nation which commands the sea must equally command her friendship; for we can hardly suppose the majority of them absurd enough to fancy that a gradual separation from all foreign connections, and a reliance on internal improvements, without a foreign market, like the policy of China and Japan, can be seriously applicable to their country at this time of day, though they have been often mentioned as models for imitation. It is therefore an imposition, too gross to be carried down, even by strong French predilection, that, although the above-mentioned view of policy be just, it affords ground for supposing that the United States can safely exchange the friendship of England for that of France.

But although it be true that the Americans may safely lie supine, like the rhinoceros, and fatten under the shade of their own forests; repelling, at the same time, from their well protected exterior the shafts of hostility; it does not by any means follow that an enlightened statesman would advise them to pursue that course. An increase of brute force, unaccompanied by civilization, was never yet considered as a legitimate object of a nation's ambition; and it is only necessary to compare the moral condition of the New England States with that of Virginia, to decide upon the results of the two systems; and to be convinced of the reasons which have induced France, subsisting as it does upon the moral no less than the political ruin of other countries, to use all its means towards assimilating the whole federal union to the condition of that southern state.

It has indeed been supposed that the different mode in which trade has been carried on by the southern and eastern states of