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In the sequel of this paper, the author explains another circumstance relating to the animal economy, which serves to prevent diseases of the heart, that would otherwise inevitably succeed obstruction in the pulmonary vessels. In subjects who had been afflicted with pulmonary consumption for some time previous to their disease, the foramen ovale was found to be open; and, in several instances, the aperture was sufficiently. large to admit the passage of a finger.

As the septum auricularum is almost constantly perfect in subjects whose lungs are healthy, (says Mr. A.) I cannot but conclude that the renewal of the foramen ovale is the effect of disease; nor will the opinion appear, on reflection, improbable; for the opening be-, comes closed by the membranous fold growing from one edge of it, till it overlcaps the other, and their smooth surfaces, being kept in close contact, by the pressure of the blood in the left auricle, they gradually grow together. But, should there be a deficiency of blood in the left auricle, and a redundance in the right, the pressure of the latter on this membranous partition will so stretch and irritate the uniting medium, as to occasion its removal; and thus a renewal of the communication between the auricles will again take place.'..

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Hence the author concludes that, in those men, or animals, who are accustomed to remain long under water, this opening will be either maintained or renewed:' but the continuance of life does not depend on this circumstance alone; for, if the blood be not oxygenated in the lungs, it is not fit for supporting the animal powers. Mr. Abernethy (in our opinion) very justly controverts the truth of an experiment related by Buffon; who says that he caused a bitch to bring forth her puppies under warm water, and then suddenly removed them into warm milk, in which state he kept them for more than half an hour, and then took them out alive; and that the submersion was repeated without injury. Questioning the truth of the fact, Mr. Abernethy immersed a puppy, soon after its birth, under water of the animal temperature. In 60 seconds, the animal lost all power of supporting itself, and would shortly have perished, if it had not been removed into the air. The experiment was repeated, but the animal could not maintain its existence by the circulation of unoxygenated blood. Animals, accustomed to remain long under water, probably first fill their lungs with air, which may, in a partial manner, oxygenate their blood during their submersion. true statement of this subject may probably be, that the circulation of venous blood will destroy most animals in a very short space of time; but that custom may enable others to endure it, with very little change, for a longer period.'

Experiments

Experiments and Observations, tending to shew the Composition and Properties of Urinary Concretions. By George Pearson, M. D.

F.R.S.

These experiments and observations are introduced by a brief historical account of the progress of discoveries in this part of science. Hence we learn that the experiments, which have been hitherto made, however considerable in the aggregate, rather afford indications of what remains to be done than demonstrations of the nature of animal concretions. Nevertheless, the subject is important; and the investigation of it, both as it is connected with chemical philosophy, and as it may lead to more efficacious and innocent practice in diseases that proceed from these concretions, cannot fail of being useful. The substance to which Dr. P.'s observations principally relate is that which he finds, by his experiments, to be very generally a constituent of both urinary and arthritic concretions. It is a substance obtained by dissolving it out of these concretions, by lye of caustic fixed alkali, and precipitating it from the solution by acids. In this way, Scheele separated this matter; but he did not consider its importance, nor of course at all investigate its properties.' Without reciting any of the numerous and well-conducted experiments, which the author made in the course of his inquiries, we shall satisfy ourselves with giving an abstract of the principal conclusions which he deduced from them.

It appears that at least one half of the matter of the urinary concretions subjected to the above experiments united to caustic soda, and was percipitated from it by acids. This precipitate does not indicate acidity to the most delicate tests; and, as it is inodorous, tasteless, scarcely soluble in cold water, does not unite to the alkali of carbonate, of potash, of soda, or of ammoniac, nor to oxide of mercury, nor to the lime of lime-water, nor decompound soap, or prussiate of iron, and, as its combination with caustic soda resembles soap, more than any double salt known to consist of an acid and alkali, this precipitate does not belong to the genus acids. As this precipitate could not be sublimed, without being decompounded, like animal matter, and also for the reasons mentioned in the last paragraph, it cannot, be the same thing as the acid sublimate of Scheele, or the succinic acid. As it does not appear to be putrescible, nor form a viscid solution with water, it cannot be referred to the animal mucilages. On account of its manner of burning in the air, under the blowpipe, and its yielding, on exposure to fire in close vessels, the distinguishing products of animal matter, (especially ammoniac and prussic acid, as well as an account of its affording a soap-like matter with caustic soda, this precipitate may be considered as a spccies of animal matter; and from its composition being analogous to that of the substances called, in the new system of chemistry,

animal oxides, it belongs to that genus. Its peculiar and specific distinguishing properties are, imputrescibility, facility of crystallization, insolubility in cold water, and, that most remarkable property of all others, producing a pink or red matter, on evaporation of its solution in nitric acid.

In his fruitless endeavours to acidify this animal oxide, the author made a discovery of the change of the most common basis of urinary concretions, (the animal oxide,) into ammoniac and carbonic acid, by the oxygen of the above acids; which discovery is curious and important, as it enables us to interpret many phænomena in a variety of cases besides the present. The 300 grains of urinary concretions, examined by the Doctor, appeared to contain 175 grains of peculiar animal oxide, 96 grains of phosphate of lime, and 29 grains of ammoniac, (and most probably phosphoric acid united to the ammoniac,) water, and common mucilage of urine.-From other experiments related by Dr. Pearson, which were made in order to obtain the acid sublimate of Scheele, or lithic acid of the new system of chemistry, he infers that there is a wide difference between this acid sublimate and the animal oxide. Accordingly, he gives to it the name, not of the lithic oxide, (agreeably to the principles of the new chemical nomenclature,) but that of ouric or uric oxide; which he conceives to be more perfectly appropriate.

For other experiments on the urinary concretions of a dog, horse, and rabbit, we must refer to the paper; and we shall conclude with observing, that the author has not found the uric oxide in the urinary concretions of any phytivorous

animal.

An Analysis of the earthy Substance from New South Wales, called Sydneia, or Terra Australis. By Charles Hatchett, Esq. F.R.S.

In consequence of the experiments of the late Mr. Wedgwood and others, this substance has been considered as a primitive earth, and has been arranged as a distinct genus in all the systematical works in mineralogy. M. Klaproth, however, in a memoir on this subject, gives his opinion that the existence of this primitive earth may be much doubted; and he apprehends that siliceous earth, alumine, and iron, are the only ingredients of which it consists. Mr. Hatchett infers, from the experiments recited in this paper, that it is composed of siliceous earth, alumine, oxide of iron, and black lead or graphite; and he does not hesitate to assert that it does not contain any primitive earth, nor any substance possessing the properties ascribed to it, and consequently that the Sydneian genus, in future, must

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be omitted in the mineral system: Mr. H. imagines that Mr. Wedgwood was led into an erroneous opinion of some of its properties by analysing it with impure acids.

ART. IX. Dissertation on the best Means of Maintaining and Employ ing the Poor in Parish Work-Houses. Published at the Request of the Society for the Encouragement of Arts, Manufactures, and Com merce having obtained the Premium offered by the Society for the best Treatise on this Subject. By John Mason Good, Author of "The Prize Dissertation on the Diseases of Prisons and PoorHouses;" published at the Request of the Medical Society of London; and of "The History of Medicine, &c." published at the Request of the General Pharmaceutic Association of Great Britain. 12mo. Pp. 151. 35. Boards. Morton, HolywellStreet, Strand.

IN a country in which millions of money are annually levied on

the community for the support of its poor, an inquiry into the best means of maintaining and employing paupers becomes extremely important. It is interesting indeed in a double view; for improvement in the system of employing and supporting them not only immediately reduces the expence, which falls so heavily on the public, but does that at which humanity feels more gratified,-it meliorates the condition of the poor themselves, and tends to render poverty less productive of vice and wretchedness. For these reasons, the dissertation before us claims a considerable share of attention;-and it is not less entitled to notice on its own account, since it treats this very important subject in a sensible, plain, and practical manner. In the first section of his, work, the author takes a general view of the origin of parochial establishments for the support of the poor. After having glanced at the different modes adopted by the nations of antiquity, in order to provide for the indigent, he mentions the first institutions of this kind which were known in England, and which he supposes to have been the three royal hospitals founded by Edward VI. in and about the metropolis, viz. Christ's and Thomas's for the relief of the old and impotent, and Bridewell for the punishment and employment of the idle and vigorous. These being found insufficient for the care of the poor throughout the kingdom, the statute of the 43 Eliz. c. 2. was enacted, which appointed overseers of the poor in every parish. From this statute, has arişen the present system of poor laws.

Mr. Good is not one of those who think that the existing poor laws are in themselves impolitic and mischievous; it is rather the manner in which those laws are executed that he

conceives

conceives to be chargeable with the evils so frequently reprobated. His observations on this subject deserve attention:

It has been said that, as the present system of laws will not permit any one to be starved, be his conduct what it may, a spirit of idleness is hereby engendered; and the man who will work is burdened with the expence and maintenance of the man who will not. That this is too frequently a fact I well know but I know likewise that it is not the fault of the law, but of the administrators of the law. So far as relates to parochial assistance the law is addressed to the impotent alone; and it authorises the overseer to compel those who are indisposed to work to labour for their own subsistence: And were this authority exercised as it ought to be; were the means of labour regularly sought after and enforced, and the impotent alone allowed relief without labour, one quarter of the two millions and half of pounds sterling, which are, at present, expended annually in support of the poor throughout this kingdom, would be amply adequate to every demand, and the poor themselves would be as much benefited as the public. But to produce this salutary alteration requires the regular attention, and unremitted assistance of the wellinformed inhabitants in every parish. It requires that vestry meetings should be frequently held, and numerously attended that the overseers, for the time being, should be selected from the most active, and the most able: that the industrious should be encouraged, the idle punished; and that one third of the public houses now existing throughout the kingdom should be prohibited.

Were exertions like these to be made in every parish, and upon the basis of the poor laws as they at present stand, we should not be perpetually hearing of their numerous defects and general irrelevancy. But while, in every parish, the present torpid conduct is exhibited by those whom it chiefly concerns, for their own interest, to be active and vigilant; while some are too rich, and some are too idle, and some are too busy to engage in parochial offices: and the important duty is hereby devolved upon the hands of those who have neither comprehension nor discrimination to perform it-it is not to be wondered at, that every species of profusion, imposition, and error, should daily take place, and be daily suffered to pass without notice. It matters not what laws, or what systems of laws are invented in a case of this kind; if those to whom the execution of those laws is entrusted, and who are deeply interested in that execution, are thus remiss, and inattentive on their part.'

Though the writer allows that the present system of poor laws is adequate to its object if rightly administered, yet he much doubts whether the prevailing mode of collecting the poor together in parish work-houses tends to any good purpose. Whenever it can be avoided, he deems the establishment of them impolitic; and therefore in villages consisting entirely of farms, and where the only inhabitants are the occupiers of those farms and their husbandmen, he believes it to be geneTally better that the overseers should attend to the poor in their

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