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violent;

exhiliration, even to the latest periods of the disease, patients affected with tuberculous phthisis have often no apprehension of their own danger.

• At the commencement of tuberculous phthisis, neither the cough nor dyspnæa are by any means urgent; and in many instances, even to the very end of the affection there hardly occurs any expectoration. The cough, in general, is of the short tickling kind, without being

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may be termed rather a tussicula than a tussis. But while it takes place without any great uneasiness, it is still troublesome from being very frequent. Notwithstanding, however, these frequently repeated efforts towards expectoration, the irritating cause is not removed, and those slight fits of coughing, terminating without the smallest expectoration even of mucus, are again speedily renewed.

• In most cases, no remarkable pain of breast attends the tubercu. lous phthisis ; and when pain occurs, it is neither fixed to any particular spot, nor is it constant.

• In many instances, no dyspnea whatever occurs in the tuberculous phthisis; or at least, difficulty of breathing is observed only upon motion or exertion. When the patient remains at rest, the breathing is perfectly free; and it is very little if at all affected by change in the position of the body. Contrary to what happens in the apostematous phthisis, the patient can lie with equal ease on either side.'

It is then remarked that the loss of strength and the wasting of the body are the first symptoms which give alarm to the friends, and the author thus concludes:

• To these slight pneumonic symptoms, even without the occurrence of any expectoration whatever, either purulent or mucaginous, distinctly marked hectic fever often supervenes. In other cases, however, after the cough has been long dry, as it is called, some degree of expectoration occurs. But in almost no instance has it the appearance either of proper purulent matter or of blood. Sometimes a slight tinct of blood is observed; but never such a degree of hæmoptysis as is often observed to precede apostematous phthisis. Most frequently, the matter expectorated is a thin watery Auid slightly tinged with blood; and it has very much the appearance of that sanies which is often discharged from scrofulous sores. When this state of expectoration takes place, hectic fever is seldom wanting to a great degree.'

The next chapter treats on hectic fever : which is stated to be a consequent disease, occurring in the latter stages of phthisis, and is sonetimes the only alarming complaint that makes its appearance. Dr. Duncan remarks that the formation of unhealthy pus in any part of the body, as well as in the lungs, is capable of producing this malady; and he adopts the opinion that it is always the consequence of ill-conditioned pus being absorbed by the valvular lymphatics, and thus introduced into the mass of blood.'. We shall not now stay to examine the

validity validity of this hypothesis, which has been much controverted. The description of the symptoms of hectic fever is well drawn up, as also that of the last stage of phthisis ; in which the extreme emaciation of the body, the great weakness, the profuse perspiration and diarrhoea, point out the near approach of the fatal termination.

After a chapter on diagnosis, Dr. Duncan proceeds to the cure; first laying down the general plan which is to be pursued, and afterward making some observations on particular remedies. The indications that are pointed out, however eligible and necessary, are, we fear, rather to be desired than expected. In the catarrhal variety, it is stated that the first object which is naturally to be aimed at in the cure, is to produce a change in that state of separation which takes place from the surface of the branches of the trachea, and of the membrane forming the air-vessels of the lungs. But it is also a second object of no less importance, to restore the natural condition and state of action of those superficial vessels from which this separation is afforded.'- In the apostematous phthisis, where the purulent matter which constitutes the exciting cause of the disease is accumulated in a considerable quantity in one or more cavities, the object is to discharge the matter collected, to prevent the formation of a new quantity, and to heal the ulcer from which it is generated. - In the last, or tuberculous variety, our endeavour must be to effect the resolution and removal of the tubercles ; which may perhaps be occasionally accomplished by the powers of the constitution, under favourable circumstances, but which, we conceive, can never be achieved by the direct interference of art.

The last chapter, containing observations on particular practices employed in phthisis pulmonalis, and which have been recommended by eminent writers,' we may regard as a compendium of the experience that has been accumulated, for a long course of years, on the powers of particular remedies or plans of treatment. It affords a favourable view of the knowlege and candour of the writer, but presents a very melancholy picture of the resourses of medicine ; since, while every person must admit that none of the remedies mentioned by Dr. Duncan can be viewed as holding out any great probability of a cure, in the largest number of instances, we feel at a loss to add to the list any that are more effectual. Bleeding, blisters, issues, emetics, refrigerants, acids, nitre, fox-glove, milk-diet, sea-voyages, a change of climate, bark, balsams, myrrh, hemlock, and inhalation of gasses, have all had their respective advocates, but have proved ineffectual in most instances in which they have been adopted by others. The remarks of the author on these different practices coincide very much with out own opinions respecting them. The observations on the several plans of regimen are equally judicious; and we also agree with the Doctor in his remark that " a greater number of cures in phthisis have been effected by regimen than by medicine, especially if under the head of regimen be included not merely diet, but air, exercise, and similar circumstances.'

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An appendix describes a process for obtaining the inspissated juice of the lettuce, as an article of the materia medica possessing many of the properties of opium, under the title of Lactucarium.

Art. V. An Account of the Basalts of Saxony, with Observations

on the Origin of Basalt in general. By J. F. Daubuisson, Member of the National Institute, and one of the Principal Engineers to the Board of Mines in France. Translated, with Notes, by P.; Neill, F.R.S.E. and F.L.S. Secretary to the Wernerian Natural History Society. With a Map of the Saxon Erzgeburge, from Petri, 8vo. Pp. 300. gs. Boards. Longman and Co.

1814. The contending partizans of the Neptunian and the Plutonian

theories of the earth require not to be apprized that the author of this treatise, in consequence of his acquaintance with the basalts of Saxony, had strenuously espoused the doctrine of their aqueous origin. Having communicated the results of his observations to some of his more fiery countrymen, they exhorted him, before they generalized his conclusions, to make the tour of Auvergne. I will do so,' he replied, and I will erect the standard of Neptune on the summit of the Puys de Dome.' To Auvergne he certainly repaired, but he as certainly returned impressed with the conviction that the basalts of that country are the products of antient volcanoes. We have not learned, however, that this opinion, which he has had the candour to avow, has shaken his belief in the humid agency to which he attributes the existence of those rocks that principally form the subject of the present volume: nor, in the nature of things, can we perceive any adequate reason for the complete dereliction of his geological creed. As volcanoes, in fact, are known to exist in districts of trap formation, ranges of basaltic rock may have been originally precipitated in a watery menstruum; and, in particular spots of the globe, portions of these ranges may have undergone igneous fusion, and have subsequently resumed their solid and stony aspect, exhibiting with more or less distinctness the traces of their former fate. By the aid of this simple hypothesis, we may at least proviRev. Jan. 1815.

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sionally sionally reconcile the conflicting arguments which have been maintained, with nearly equal plausibility, relative to the production of basalt in general. Waiving, however, at present, the discussion of this much debated question, if we convey to our readers adequate conceptions of the scheme and merits of M. Dąubuisson's publication, we shall rest satisfied with having discharged our critical duty.

In a short introduction, the author states the points of controversy between the advocates of the rival theories, glances at the intermediate opinions of Saussure and Dolomieu, and thus announces the plan and objects of his essay:

• In order to obviate any doubt as to the meaning of terms, I shall begin with explaining what is here to be understood by basalt, and by the expression volcanic production. Then, after giving a concise sketch of the position and nature of the chain of mountains, I shall particularly describe each basaltic eminence in succession. I shall next mention the conclusions which seem to me to result from my observations, particularly in regard to the formation of the basalts of Saxony: stating my reasons for believing that they are not, and sannot be, of volcanic origin. After having taken a cursory view of the extent of the great basaltic' mass which constitutes a part of the surface of the globe, I shall hazard an opinion concerning the nature. of basalt in general ; and then conclude with an examination of the volcanic hypothesis of that excellent geologist Dolomieu, whose misfortunes lately excited so much interest among the learned in every part of Europe, and whose recent loss is still generally deplored. These different matters will form the objects of the five parts into which this essay is divided.'

Without attempting to give a definition of the term basalt, he enters into a rather detailed description of its more general characteristics; which, since they do not materially differ from those that are observable in the same mineral substance as it occurs in our own island, it would be superfluous here to particularize. Under the denomination of volcanic préductions, he includes only those substances which have undergone complete fusion, and have had their nature changed by a subterranean fire,' &c. : but we can conceive rocky matters fused by volcanic heat, and subsequently consolidated, without having their stony, nature or aspect changed. Basalt, if we mistake not, is often found in this very predicament, as we may infer from the experiments of Sir James Hall, and from various undoubted lavas brought from Hecla, the Isle of Bourbon, Auvergne, &c. On this and some other points, connected with the phænomena of burning mountains, we could have listened with greater deference to the author's observations, if he had personally contemplated the process of a volcanic eruption, and not ena, deavoured to mix it up with the comparatively insignificant 3

combustion

eombustion of thin strata of coal, at a few yards from the earth's surface.

The basaltic mountains of Saxony appear to be singularly situated in a geological point of view, as they belong to the Erzgebirge, or metalliferous chain; which, running one hundred and twenty miles from N.E. to S.W., separates Bohemia from the electorate of Saxony: terminating, on the one hand, in Franconia, where its base unites with that of the Fuchtelgem bürge; and, on the other, in the great and deep valley of the Elbe. It rises to 3,600 feet above the level of the sea, and has a very rapid declivity towards Bohemia, but a very gradual descent towards Saxony. Its fundamental rock is granite, which is wrapped round, as it were, with beds of gneiss, micaceous shistus, and slate; through which, in many places, it pierces, and appears exposed to view. The numerous and rich veins which traverse some of the beds are the objects of the great mining operations in Saxony. In this chain are likewise found rocks of serpentine and quartz, strata of lime-stone, coal, clay, &c. A powerful bed of porphyry covers the whole of the eastern part of the chain, on the northern side; as, a bed of sand-stone, of equal magnitude, does on the southern.

« On a chain of hills of this structure, does the basalt rest, of which I am to treat. Under various shapes, as tables or platforms, cones, and domes, it forms the summits of about twenty mountains," some of which are isolated, but which more generally are connected by their sides to the neighbouring mountains, the basaltic top alone remaining separate. This is commonly the most elevated point in the neighbourhood ; so that when, in surveying the aspect of any part of the chain, an isolated summit is seen rising above the sur. rounding mountains, we may almost conclude that it is composed of basalt. It is principally in the neighbourhood of the ridge of the chain that mountains with basaltic summits occur. Precisely on the highest part of the chain, between Gottesabe and Irgand, there is a kind of mountain-plain, more than three miles in length, the rock of which is basalt. The back of the chain, which looks towards Bo. hemia, presents a greater number of basaltic mountains ; but I mean here to confine myself to those of Saxony.'-. All the basaltic rocks of Saxony, taken together, present a surface of little more than an English square mile, and they are dispersed over an extent of country of more than six hundred square miles, so that they do not constitute the six hundredth part of the superficies of the chain of which they form a part.

Many pages are allotted to a geological analysis of the respective hills in question, with the particulars of which we are little anxious to swell our report ; not because we are at all inclined to challenge their accuracy, or to detract from their real value, but because, with the exception of some of the accompaniments which we have already noticed, the phænomena do D 2

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