Our limits do not allow us to dilate up one very interesting department of this subsea —the prolongation of dormant vitality mid's paiticular circumstances in frogs and other reptiles. Many marvellous stories of this kin I are on record ;—such as the inclosure of thee animals in solid blocks of granite or other igneous rocks, which no well-informed person can credit. There are, however, a sufficient number of authentic cases to prove, in the esti mation of those who have fairly examined them, that toads and other reptiles may be en closed in masses of rock apparently solid, or in the substance of the trunks of trees, and that they may preserve their vitality under sucsi circumstances for a very long period. In the former instances, it would appear that the ani mal has Ellen into a chink or crevice, which has been gradually filled up by the washing-in of gravel or other materials disposed to soh dify ; and that thus the appearance of a solid mass has been given, when in reality some com munication has existed between the cavity and the external air. It is by no means impossible, moreover, that these animals might be found imbedded in the sandstones at present in course of formation in many localities; these rocks possessing considerable hardness, bist being at the same time sufficiently pore allow of the slow passage of air throu substance. Where toads have becom bedded in crevices of trees, and be rounded by new layers of wood, it is es that a direct communication with the atmo phere will probably exist by means of the or ginal crevice, although it. may be much nar rowed ; but even if this be not the case, the porosity of the wood will furnish the required condition. Some amount of access of air would seem, from the experiments of M. Ed wards and Dr. Buckland, to be essential to the prolonged vitality of toads enclosed in solid masses ; and this will probably maintain a vety feeble respiratory action upon the blood throtmli the general surface, just sufficient to prevent the decomposition of the body. Vital action cannot, therefore, be regarded as so completely extinct under these circumstances as in some of the cases formerly mentioned, where the ap plication of cold has not only completely checked it, but has also done away with the necessity for it, by completely subduing the tendency to decomposition.
In the human economy, as in that of other non-hybernating animals, it is only occasion ally that anything approaching to this suspen sion of vital action can occur. That which takes place during sleep only relates to the sensorial functions; the organic changes expe riencing but little diminution in activity. The closeness of the connection between their vital operations, and the immediate dependence of these upon external stimuli, involve the de struction of life when they are totally with drawn; and it is only under peculiar conditions of the organism itself, that we ever witness a suspension of vital action without the speedy supervention of death. Indeed it may be fairly questioned whether such suspension can ever completely take place; and whether the changes which occur in the periphery of the circulation are not continuing, however feebly, even when no action can be detected at the centre. This condition is termed syncope ; and its phenomena will be more fully detailed here , after. (See SYF.copE.) We are inclined to think that, where a state of apparent death has conti nued for some days, vital action was never r entirely suspended ; though perhaps its cessa tion may be more complete where the syncope is but transient. Such would seem to be the case where individuals have recovered from a submersion under water, which has been pro longed beyond the few minutes that suffice to produce asphyxia. It is generally supposed, and we think with reason, that the mental emo tion experienced at the moment of submersion produces a state of syncope ; and that the or ganism, being in that state less dependent on external stimuli than when in a more active condition, can bear privations which would be otherwise fatal, just as is known to be the case with hybernating animals, the pupae of insects, &c. The well-known case of Col. Townsend
appears to us to prove that an apparent cessa tion of vital action does not imply its entire extinction ' • since when no changes could be detected by his medical attendants, he was vo luntarily acting on his system both to retard and renew its usual functions. Dr. Cleghorn of Glasgow knew an individual who could control the action of his heart, so as to be able to feign death at pleasure.
Although in these cases we may be disin clined to admit the total suspension of vital action, there can he no doubt that it may occur in portions of the human body under the influ ence of cold, and that, if carefully treated, it may be again renewed. Nay more -- there is undoubted evidence that portions of the body, after being totally separated from it, may be reunited and made again to form integrant parts of the structure, if no disorganisation has taken place in the interval. That such an occurrence is perfectly consonant with the doctrines which we have maintained regarding the connection between vitality and organisation—will be at once evident; but we do not see how it can be satisfactorily explained by the advocates of the doctrine of a separate life or vital principle. Does the finger or nose which has been cut off carry with it a chip or off-shoot of the parent vital principle or organic agent? If so, when does that quit its material tenement ? There is no evidence of its existence in the separated part, which is completely dead to the general structure, and which nothing prevents from speedy decay, if its vital actions be not soon renewed. And if it be supposed to remain, it must again become merged in its parent prin ciple, when re-union of the divided parts has taken place, or must submit to it like a dutiful child. There is no end to the absurdities in which those may be involved, who adhere with pertinacity to a doctrine so useless and so un philosophical as that of a single controlling agent or power, presiding over the affairs of each organism.
It is with much satisfaction that the author of the foregoing article (which was written above a year ago) refers his readers to the re cently published Supplement on the Atomic Theory, by Dr. Daubeny, for a full discussion of the question briefly considered in § V. The conclusions at which Me learned Professor has arrived are of precisely the same character as those for which the author has here argued, and are expressed in almost the same language. The following passages may be extracted from among many of great interest.
" There is little doubt that it will eventually appear, that all the secretions or excretions of animals and vegetables are only so far de pendent upon inasmuch as, in consequence of the favourable temperature which it sustains, the constant circulation of the fluids it occasions, and their exposure to external agents in vessels of different shapes and dimensions, a mechani cal separation of the ingredients of the blood is effected in some instances, and a chemical change produced in its composition by catalytic action in others." "The putrefaction of vege table and animal matters appears to be produced, not by any sudden cessation of those affinities which had previously bound their respective elements together, but by the predominance over them of the natural forces, which we may without much difficulty conceive to have been controlled under the circumstances in which the living body is placed; nor does there seem any sufficient reason for calling in the intervention of an occult principle to explain that, to the solution of which by known causes, every fresh advance in chemical knowledge seems to bring us into closer approximation." " It is now cer tain that the same simple laws of composition pervade the whole creation ; and that, if the organic chemist only takes the requisite pre cautions to avoid resolving into their ultimate elements the proximate principles upon which he operates, the results of his analysis will show that they were combined 'precisely according to the same plan as the elements of the mineral bodies are known to be."