this account, they are not refponfible Those who take the trouble to prepare this publication are aware, that in this fubject theory is good for nothing till fanctioned and confirmed by experience; that old modes of husbandry ought to be held in refpect and changed with caution and moderation, and that farming by books merely, is juftly derided. At the fame time they are convinced that Agriculture derives aid from the difcoveries and labours of the philofopher, the naturalist and the chemist; that principles grow out of practice; and that inquiry is the road to improvement. They have no more refpect for a bigoted attachment to injudicious cufloms, than for a rafh fpirit of innovation; nor can they afcribe wifdom or modesty to The different refults of the experi- "Nor thou the rules, our fathers taught, defpife, ally excite attention, and probably put The obfervations on the progrefs of vegetation in the next paper, comprise a part of natural hiftory, which is evidently applicable to the use of agricul ture. A fufficient number of notices of this kind would afford the best fort of almanac for regulating feed time. It is hoped gentlemen in various parts of the country will frame and fill up fimilar tables. "Where the feveral trees, shrubs and plants, here mentioned, are wanting, they may be supplied by other kinds. The field or the wood will compenfate the deficiency of the garden. We publish a new confirmation and illuftration of Mr. Cooper's doctrine and practice, refpecting feeds, as related in a letter of his in a former number, and it is to be wished that every farmer will endeavour to teft and be able to verify them for himself. The sketch of foils and manures muft be useful to all who would have the habit of difcriminating the several species of each, and adapting culture accordingly; and the analysis of lime and marl requires fo much knowledge of chemistry only as can be learned and applied by the common farmer. The treatife on the culture and preparation of hemp being intended for the inhabitants of Canada, is of courfe applicable to our inftruction. The efficacy of falt in curing clover is proposed to the ferious attention, and the careful experiments of farmers. The documents here published will show how much reafon there is to expect it will be found highly beneficial; and the premium offered by the trustees, is added to other inducements, for giving it further trials. The files of the Society contain a number of fets of answers to Agricul tural Questions fent out by the trustees fome years ago. They delay making ufe of what they have, in hopes of more. Will farmers, into whofe hands they are put, favour them with their answers that they may proceed to give the public the information received either entire or digested? For this and other affiftance in fulfilling their office, the trustees look not only to intelligent individuals, but to the agricultural affociations in different parts of the state, to fome, or most of which they are already indebted; and to one for the first document in this pamphlet. In the name of the Society, the trustees repeat their request to thefe affociations for original communications, and their affurances of ability and readiness to publifh for their and the general benefit whatever novel, interesting or feasonable matter, they fhall put at their difpofal. THE interesting phenomena of refpiration, and the production of animal heat, have of late years clofely engaged the attention of philofophers; and the difcoveries of the modern chemical fchool have much enlightened this curious and important fubject. But thefe phenomena, like most others of the animal economy, are ftill enveloped in an obfcurity which the most accurate obfervations and the most industrious experiments have not perfectly diffipated. The learned Dr. Black remarked that animals which have lungs are warmer than all others; and that there is an intimate connection between the frequency of refpiration and the degree of animal heat. Hence he naturally suspected, that the lungs inftead of being, as was then believed, a pair of bellows for cooling the body, were themselves the He producing caufe of heat. purfued and investigated this idea. Many others following him have difplayed fuch a multitude of facts to prove this opinion, that it has become the received doctrine through the learned world. A few philofophers, either ftaggered by fome oppofing facts or attached to the old fyftem, still reject this theory, and offer in its place fome one, and fome anoth er. Among these we must class the author of this difcourfe ; whofe ideas appear to be in part novel, and partly coincident with the ancient opinions. The origin of animal heat is by him believed to be quite diftinct from the refpiratory procefs; and dependant on a fubtle, incomprehenfible, and unintelligible principle. Animated bodies, (fays he,) from their particles, poffefs the property of the nice and peculiar arrangement of maintaining that action, which the first impulfe of motion commences, and of longer refifting the perpetual nifus for an equilibrium. Animal heat is an efrion of the existence of this diftinguishfect of this property, and is the crite ing characteristic. The fucceffive expanfions and contractions, then, of the animal fibres, conftitute those vibrations which we call life, and they are equally fame univerfal caufe, which first gave dependant upon the fame principle, the motion to matter. Vain and prefumptuous is the attempt to discover this principle, by anatomical inveftigation or chemical analysis; for its evanefcent existence waits not their refults, and the its escape. moment of research is but the signal for As thefe "fucceffive expansions and vibrations" are dependant on a principle, which the author thinks it improper to investigate, we cannot ask him for facts; and we may be excufed for declining the refutation of an unfupported cpinion. But furely it might as juftly have been faid at once, as fome one has faid on another fubject, "That the animal heat exifts becaufe the Creator has fo willed it." After thus combating the idea that heat is derived from the lungs, the author proceeds to confider the use of refpiration, and commences with an account of the manner in which he conceives it to begin. Immerged into the atmosphere (the animal at birth) immediate evaporation is the effect of the first contact of air upon its delicate furface. A fudden contraction is the neceffary confequence. This is the firft ftimulus, and like the electric with which it may the caufe of the first contraction of the mufcles of infpiration to be evaporation from the surface of the fkin which covers them; and that of the first contraction of the mufcles of expiration to be evaporation from the internal furface of the lungs. Supposing the first to be true, the fecond is inadmiffible. For the lungs have no contractile power of their own, and there is no reafon why the diaphragm and abdominal muscles fhould not be contracted by the us, as well as by the internal ; propagation of the external ftimuand as the former exifts first, it muft operate firft. Nor do we know any fact to prove that mufcles are dependant on each other identified, it immediately pervades the for their powers. They are all whole fyftem, although we obferve it dependant on the nerves. But is only, where fome obvious effect is pro- it true that evaporation is the duced. In confequence of this evapo- caufe of the first contraction of ration, the intercoftal mufcles are contracted, the ribs are raifed, and the dia- fhows that it is not. For if an the mufcles of infpiration? Fact phragm is drawn down; thus is the cavity of the thorax enlarged, and thus infant be covered at the inftant it are the lungs expanded. Then, and not emerges into the air, it will not till then, is the air admitted, and the cry the less infpire. On the contrary, which fucceeds is no more than the index of when in the new born infant, the this occurrence. The undiquaque preffure action of refpiration does not of the atmosphere would preferve an equilibrium, and thus expanded would commence of itfelf, it is fomethe lungs remain, did not the infpired times promoted folely by plungair deftroy the balance by producing ing the infant under warm water, evaporation, and there again exciting, where no evaporation can take place from its furface. After fome remarks on the changes which air undergoes in the lungs, the theory is thus concluded: be contraction. The ftimulus is inftanta-" neously propagated, and the abdominal mufcles with the diaphragm, by their reaction become the ready and efficient auxiliaries in the office of expiration. Thus the fucceflive application of the fame ftimulus produces the alternate expanfion and contraction of respiration, thus are the blood veffels on the furface, and in the lungs fucceffively excited to propel their contents, and thus is life maintained by the reciprocal abstraction of its effential principle. If we rightly understand this piece of theory, the author thinks The function of refpiration then is to originate, and maintain a certain motion of the animal fibre effential to vi tality, and the effect is produced by the contraction from evaporation, excited by atmospheric air, which from its particular compofition, and the eafy and various change of its application, is peculiarly fitted for this purpose. But it fhould feem, that the originating a "certain motion of the animal fibre" were quite a ufelefs office for the lungs, if we believe, what is before afferted, "that the expanfions and contractions of the animal fibres, which conftitute thofe vibrations we call life, are equally dependant upon the fame principle, the fame univerfal caufe, which first gave motion to matter." We might adduce many facts, which make it appear improbable that evaporation from the lungs is the ufe of the refpiratory function. As this feems unneceffary, we will offer only one of the fimpleft. According to this theory, whatever increafes evaporation from the lungs ought to increase the facility of refpiration. As heat promotes evaporation, hot air fhould be better for refpiration than cold : But this is contrary to fact; for every one has felt that it is more laborious to breathe during the violent heats of midfummer, than in the cool breezes of autumn, or even the fevereft colds of winter. the licentioufnefs of political publications, with which our newipapers abound. But it fhould be remembered that philofophy demands the feverity of argument and the accuracy of fact. The truth is, that the diftinctive characters of fenfible and latent heat were observed by Dr. Black before the existence of this theory of refpiration; that many philofophers and chemifts have made experiments on this fubject, entirely diftinct from and without any reference to refpiration; that the whole body of modern chemifts agree in the general experiments on this matter; and that fuch a number of clear and deci five facts and experiments have been made upon it, as fcarcely any other chemical doctrine poffelles. We must believe that the author has not fufficiently adverted to thefe things. The difficulties attendant on an accurate examination of the gafeous fluids concerned in refpiration, have attracted fome re"A few remarks" afe occa- marks. It is obferved that tho' fionally made by the author "on a quantity of oxygen disappears the received fyftem, which," in in the lungs, there is no proof his language," feems, if not to that it is abforbed by them. have fatisfied, almoft to have This is true; but it is also true, filenced inquiry." He however that we have no proof of the prepares the way for an eafy and whole quantity being employed in entire fubverfion of this formida- the formation of water and carble theory, by a bold affertion bonic acid gas.-Here we are that the diftinctions of fenfible for once forced to relinquifh exand latent heat were invented for periment and reafon from analthe exigencies of their employers. ogy. The process of refpiration We lament for the fcientific repin many respects refembles that of utation of our country, that fuch combuftion. The latter cannot expreffions fhould be put forth by exift without air: nor can the a literary and a medical charac- former. They both vitiate the ter. General and unfupported air which they ufe, and destroy affertions are not uncommon with its power of fupporting them. us. They take their origin from They alfo equally vitiate the air for each other. Both are incapable of being carried on in the noxious gafes. In fine, it appears that a certain principle of air is alone capable of fupporting combuition. Abstract this principle, no combustion can take place, nor can refpiration go on. This principle is oxygen. This is the principle which supports combuftion; and when ufed pure, increafes it to a violent degree. We must acknowledge, then, a clofe analogy between combuftion and refpiration. In the former procefs, we can prove that oxygen is abforbed. Is it not probable that it is fo in the latter? It would be abfurd to affert that combustion is carried on by evaporation. Perhaps it is fo of refpiration. If evaporation is the only effect neceffary to be produced by ref pirative air, any gas having a fufficiently ftrong affinity for moif troy facts, fupported by the clearest and most beautiful experiments In the practical part we find, that the author difapproves inflation of the lungs with the breath of another perfon. Though atmofpheric air is certainly preferable when it can be conveniently thrown in; we could inform him of numberless cases of new born infants in a state of asphyxia, who have been eafily recovered by inflation from the human lungs. Thefe would many of them have perifhed, if left for a few minutes in order to prepare a better apparatus. The ftyle of this production is eafy and agreeable; and fome parts of the theory poffefs confiderable ingenuity and marks of an original and unfettered genius. ture, fulphurated hydrogen gas LITERARY INTELLIGENCE. for example, would be as proper for respiration, as atmospheric air. We have room for only one more remark on this new theory. In one place, (p. 12) we find it obferved, that the difappearance of oxygen in the lungs may be accounted for by its combination with the carbon and hydrogen, which we know come from the blood in the lungs. At the fame moment it is denied, that oxygen can be absorbed by the blood becaufe the coats of the lungs intervene. Why fhould carbon and hydrogen país out, more eafily than oxygen can pafs in? Afterward, however, (p. 15) it is queftioned whether there is any decompofition of air in the lungs, Here we again remark, that neith er affertion nor queftion will def Late Publications. At Philadelphia.-A Commercial Dictionary, published by James Hum phreys. A handfome edition of Pinkerton's Geography, in 2 vols. 8vo. with a 4to. volume of maps executed in a mafterly manner. This edition may rank with the best that has iffued from the prefs in this country. The Hiftory of Mexico, collected from Spanish and Mexican hiftorians, from MSS. and ancient paintings of the Indians, illuftrated with charts and engravings in a fuperiour ftyle, with critical differtations on the land, animals, and inhabitants of Mexico; by Abbé D. Francefco Saveria Clavigero. The Refuge, by the author of the "Guide to Domeftic Happiness.” At Boston.-A valuable work on the Truth and Excellence of the Chrif tian Religion, by Hannah Adams. |