Imatges de pÓgina

much efficacy to every thing scarlet, probably from its fiery bue.

Chapter VI. is headed, ' From the fifteenth to the middle of the seventeenth century-Fire, philosophy, and the alexipharmic treatment. The author has here shown the same able discrimination of character, in his biographical sketches of the writers, whose doctrines he briefly describes, and characterizes by some pointed quotation or appropriate anecdote, as well as the same intimate acquaintance with their works. Fracastorius, Paracelsus, Fernel, Forestus, Mercurialis, Sennertus, Van Helmont, Willis, Riverius, Diemerbroek, Kircher, Sylvius, and some others, are thus passed in review, with an account of their opinions and practice in respect to the small-pox.

In the VII. Chapter, the author treats of the cold treatment-Sydenham, Boerhaave.' Between these two luminaries of medical science, he has also given brief accounts of the opinions of Etmuller and Doldus. His biographical sketch of Sydenham is short; but his detail of the particular improvements in the treatment of small-pox, which Sydenham introduced, is very copious; and he justly laments the hypothetical error, of bleeding in the last stages of confluent small-pox, into which that able physician fell

. Boerhaave admitted that the history of small-pox and measles, which Sydenham left, could rot be improved; but from bis general reasonings on febrile diseases, he had the merit of introducing two essential improvements on the practice of that author, the exhibition of aperients in the beginning, and changing the antiphlogistic for a cordial regimen towards the conclusion of the confluent small-pox.

In the three following chapters, the author has given an ani. mated account of the discovery and progress of inoculation, from the Chinese custom of sowing the small-pox, down to the improvements made by the Suttons, Dimsdale, and others; together with a detail of the controversies which it excited, and of the various pablications, religious and medical, to which it gave rise in this country. And in the eleventh, and last, chapter, he treats of the opinions of Dr Cullen, and of the final treatment in which physicians at length terminated their dissensions. Mr Moore then inquires into the result of the labours of twelve centuries to remedy this malady; and confesses that the view is rather mortifying 10 a medical philosopher. The immense general mortality, however, he jusily remarks, is not disgraceful to the art of medicine, because in individual cases the fatality of the disease has been much diminished by the improvements in practice, and especially by inoculation; and indeed in no disease perhaps has the salutary influence of medicine been more conspicuous. For in countries, where igno. rance of the disease prevailed, the small-pox has proved a most fatal pestilence; but here, a very large proportion of the community, who submitted to professional instruction, have escaped all the calamities incident to the disease. The mischief has arisen principally from the difficulty of inducing all persons to resort to inoculation; and under that impossibility, it has been increased from the want of some laws of exclusion, analogous to those of quarantine, by which those, who produce the disease by inoculation, should be prevented from exposing the inoculated persons in the way of those who are liable to the infection. A recent decision in the Court of King's Bench, however, has shown, that such an exposure, where it produces the disease in others, is a misdemeanour by common law; and a medical practitioner, and an ignorant mother, have recently been subjected to imprisonment for being guilty of this act. We submit to the most severe laws of quarantine, for the sake of evading the introduction of foreign contagion, (laws which allow any individual to take the life of a person seen in the act of breaking them); and there seems no sound reason why we should not guard against the wilful propagation of domestic contagion, by a law, which should preclude all persons infected with the small-pox from mixing with the public.

• Some opposition,' says the author, in his concluding paragraph, • might be expected from those who live by spreading contagion among the community. But there are a set of men whose immoral conduct merits rather the castigation of the magistrate, than the consideration of the legislature. And few even of them would have the effrontery to raise objections to a statute for extinguishing the most fatal pestilence that ever preyed upon man ; which, like the benign law for abolishing the slave-trade, would reflect lustre on the mover, adorn the annals of parliament, and add grace to the sovereign ; and would likewise form (though it may spoil the climax) the most agreeable conclusion possible to the eventful History of the SmallPox.'

The foregoing sketch of the contents of this work will afford some idea of the very complete view which the industry and ability of the author bave enabled him to present of the evidence which is extant respecting the progress and treatment of the small-pox; but it will afford no adequate impression of the various collateral information, connected with medical history, with which it abounds, and of the sprightliness of the manner in which it is detailed, both of which contribute to extend its interest beyond that of the medical reader.


Some Additional Experiments and Observations on the Relation

which subsists between the Sanguiferous and Nervous Systems. By A. P. WILSON PHILIP, Physician in Worcester. From the Philosophical Transactions of 1815, & M. le Gallois founds many of his opinions on the supposi

tion, that the circulation nearly ceases in any part when the nervous influence is withdrawn from it, Dr Philip made the following experiment, to ascertain how far this opinion is well founded. After destroying the spinal marrow of a frog, by a wire introduced into the

spine, and moved about in it, he brought the web of one of the hind-legs into the field of a microscope, and found the circulation in it as vigorous as in a healthy frog; and he refers to several experiments related in his former paper, to prove, that the circulation is equally independent of the nervous system in warm-blooded animals. The above opinions of M. le Gallois, therefore, he regards as unfounded, and conceives that the phenomena to which they relate, can only be explained on the principles laid down in his former paper, the principles hitherto assumed by physiologists not applying to these phenomena. Referring to this paper, he observes,

One part of the subject I left untouched, as it seemed at first sight to open too extensive a field of inquiry. It was evident, in making the experiments related in that paper, that the laws which regulate the effects of stimuli applied to the brain and spinal marrow, on the muscles of voluntary and those of involuntary motion, are very different.'

In the present paper, he relates six experiments, made with a view to ascertain the circumstances in which the effects of scimuli, acting through the nervous system on these two sets of muscles, differ.

The Ist experiment shows, that passing a wire in various directions through, or even cutting slices from the brain, does not at all affect the muscles of voluntary motion, except when we approach those parts of the brain from which the spinal marrow or nerves originate ; while the muscles of involuntary motion are affected by mechanical stimuli applied to any considerable portion of the brain, no one part appearing to affect, them more than any other.

The 2d experiment shows, that strong spirit of wine ap

plied, either to the surface or any other part of the brain, even to those parts from which the nerves originate, produces no effect on the muscles of voluntary motion; that, applied to the surface, it readily increases the action of the heart, and increases it to a greater degree when applied to the internal parts. An infusion of opium produced the same effect on the heart, but in a less degree. Under the term brain, he includes both the cerebrum and cerebellum. He could not observe that the heart was more or less affected, either by chemical or mechanical stimuli applied to the cerebellum than to the cerebrum ; nor could he affect the muscles of voluntary motion by wounding the cerebellum, unless the instrument was made to approach the origin of the spinal marrow or nerves.

It appears, from the 3d experiment, that no chemical stimulus, except the most powerful, the concentrated mineral acids, can excite the muscles of voluntary motion when applied to the spinal marrow; but that both spirit of wine, and a watery solution of opium, applied to this organ, readily increase the action of the heart.

From the 4th experiment on this part of the subject, that is, the fifth of the paper, it appears, that after the brain and spinal marrow could no longer excite any contraction in the muscles of voluntary motion, both were still capable, when stimulated, either mechanically or chemically, of increasing the action of the heart.

From experiment 6th it appears, that we cannot, by stimulating the brain, excite irregular action in the heart, which is so readily excited in the muscles of voluntary motion.

Experiment 7th shows, that the effect on the muscles of voJuntary motion chiefly takes place at the time the stimulus is first applied to the brain; that on the heart continues as long as the stimulus is applied, unless it is of such a nature as to produce the sedative, after the stimulant effect.

- The sedative effect,' he observes, was so far from being the consequence of the previous excitement, as many physiologists have supposed, that spirit of wine, and mechanical stimuli, which produced no sedative effect, but continued to stimulate the heart as long as they were applied, produced a much greater degree of excitement than tobacco, whose slight stimulant effect was quickly succeeded by a powerfully sedative one.'

From experiments 8th, 9th, and 10th, it appears that neither mechanical nor chemical stimuli, applied either to the brain or spinal marrow, affect the action of the heart, unless they make their impression on a large part of these organs. It also appears, from some of the experiments above alluded to, that the

heart obeys a much less powerful stimulus than the motions of voluntary motion do. On these two facts Dr Philip founds his explanation of all the differences obsepved in the effects of agents acting through the nervous system on the muscles of voluntary and involuntary motion, for which we refer to the paper.

The experiments by which he has ascertained that the heart is influenced by every part of the brain and spinal marrow, led him to inquire by what means the heart is so influenced. He observes,

• It appears, from the foregoing experiments, that the heart is influenced by every part of the nervous system ; and, in a former paper, I pointed out why we have reason to believe that the intestines obey the same laws with the heart, although this cannot be so directly proved. From the situation of the ganglia, compared with the whole of the experiments here alluded to, I think we cannot help believing, that their office is to combine the influence of the various parts of the nervous system, from which they receive nerves, and to send off nerves endowed with the combined influence of those parts. Without some such means, it would be difficult to conceive how any organ should be influenced by every part of the nervous system. We cannot suppose that it receives nerves from every part of this system. Indeed, we know that no organ does so. The following seems to be the state of the question.- We see some parts influenced by every part of the nervous system, others only by certain small parts of it. In the latter instances, we see nerves going from these small parts directly to the parts influenced. In the former instances, namely, where it is found that the part is influenced by all parts of the nervous system, we see no nerve going directly from any part of this system to the parts influenced ; but we see these parts receiving nerves from ganglia, to which nerves from every part of this system are sent. It is therefore evident, from direct experiment, that the nerves issuing from ganglia convey the influence of all the nerves which terminate in them, to the parts to which they send nerves ; and, consequently, that this is one tise of the ganglia: nor does there seem any reason to induce us to believe that they have any other use. Thus it would appear that the ganglia and nervous filaments connecting them, which have been called the great sympathetic nerves, are, if I may be allowed the expression, a channel of nervous influence, flowing from every part of the brain and spinal marrow, from which those organs are supplied which are subjected to the whole nervous system ; those subjected to any particular part of this system being supplied directly from that part. This view of the subject is consistent with the observations of anatomists, who remark, that the great sympathetic has by no means the character of a nerve. Nothing, surely, can be more different than this string of ganglia, and a nerve, such as it passes from the brain and spinal marrow to the muscles of the trunk or limbs. It may also be worth

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