avoid altogether the operation on the bowels, the stimulant operation on the stomach and general system might be exerted by these waters, similar to that of the Bath waters, and under this form they might prove useful in diseases very different from those in which they might otherwise be employed. As they would require, too, large dilution to reduce them to this state, the temperature of the Bath water might easily be given, by adding the requisite proportion of hot water, by which a greater similarity of operation would be obtained. And the Dunblane water in particular, containing so much larger a propor tion of iron than the Bath water does, the dilution requisite to give it the same strength, with regard to the muriate of lime, would still leave an equal degree of chalybeate impregnation. If the preceding observations, therefore, are just, the Dunblane and Pitcaithly waters may be converted, in all the essential parts of the chemical composition, into a water similar to that of Bath.

"From the preceding statement of their composition, it is easy to discover how this may be done. To give the same proportion of the principal ingredient, the muriate of lime, the Dunblane water would require to be diluted with from six to seven parts of pure water; the same degree of dilution would bring it to nearly the same strength with regard to the iron; if a pint of it were diluted with this proportion of water, about 35 grains of sulphate of soda would require to be added, to render the composition, with regard to this ingredient, perfectly alike, if this were thought essential. The only remaining differences would then be, the presence of about 2.8 grains of muriate of soda in each pint of the reduced Dunblane water, the deficiency of 5.5 grains of sulphate, and 0.7 grain of carbonate of lime, and the absence of 0.2 grain of siliceous earth, differences in all respects probably of no importance whatever. The simple expedient, indeed, of diluting one part of the Dunblane water with from six to seven parts of warm water, (or if the sulphate of lime in a state of solution should be supposed to be possessed of any active power, with four or five parts), and adding, if the chalybeate impregnation were not found sufficiently active, a few drops of tincture of muriate of iron, would probably serve every purpose. And if sufficient confidence could be given to the substitution on the part of those employing these waters medicinally, the Dunblane water, thus altered, might probably be taken with as much advantage as the Bath water in the diseases in which it has been found useful.

"It is obvious, too, that if the artificial preparation of the Bath water were attempted, it could be done much more easily according to this view, than by endeavouring to dissolve the actual products of its analysis, which, indeed, it would be impracticable to do. Muriate of lime, and sulphate of soda, dissolved in water of the due temperature, with the addition of a minute portion of muriate of iron, would probably afford a composition approaching as nearly to the natural composition, as is either practicable or necessary in the imitation of any mineral water."

In the latter part of this valuable paper, Dr Murray takes a similar view of some other mineral waters.

The analysis of Cheltenham water "affords sulphate of soda, sul phate of magnesia, and sulphate of lime, with muriate of soda, mu. riate of magnesia, carbonate of magnesia, and oxide of iron. There is no just reason, however, to infer with certainty, that all these are its real ingredients. It is as probable, and, indeed, more so, that, previous to the evaporation by which they are obtained, it contains muriate of lime, which being acted on by the sulphate of soda, forms muriate of soda, and sulphate of lime. It is even not improbable, that the carbonate naturally existing in the water is not carbonate of magnesia, but carbonate of soda.

"The water of Harrowgate affords in its saline ingredients another illustration of the same views. The principal ingredient is muriate of soda, with which are present muriate of magnesia, muriate of lime, sulphate of magnesia, carbonate of magnesia, and carbonate of lime. Now, nothing is more probable, than that the two last substances are not original ingredients, but are products of the analysis, formed by the action of carbonate of soda existing in the water on portions of its muriate of magnesia and muriate of lime, whence also the quan. tity of muriate of soda is increased."

Seltzer water, "according to Bergman's analysis, contains in au English pint,

"But adopting the opposite view, the composition, so far as the uncertainty of the state of the products, to which Bergman's estimate is referred, admits of calculating the proportions, will be,

"This view of the composition of this water, accords much better than the other, both with its sensible qualities, and its medicinal powers. Its taste, after the carbonic acid has escaped from it, on exposure to the air, is rather strongly alkaline, which would scarcely be the case, if it contained only four grains of crystallized carbonate of soda in a pint, but which is to be expected if it contain eighteen grains. It operates as an antacid and diuretic, and is productive of much benefit in all dyspeptic affections, in diseases of the urinary organs, and in those general affections of the system which require a mild tonic power. There are few mineral waters, Dr Saunders observes, which have acquired a higher reputation; and there are few, he adds, that

deserve greater consideration, from the real medicinal virtues it possesses. It will be difficult to give a satisfactory account of the origin of these virtues, if we regard it as water impregnated with carbonic acid, holding in solution so minute a portion of carbonate of soda, with the larger proportions of muriate of soda and carbonates of magnesia and lime. But if we consider it as containing along with its free carbonic acid, a considerable quantity of carbonate of soda, with smaller proportions of muriate of soda, muriate of magnesia, and muriate of lime, we assign to it a composition of much greater power, and adequate to account for the effects it produces. Such is the activity of this water, that its medium dose is only half an English pint, a degree of power which accords much better with the one view of its composition than with the other."

It is impossible to read these extracts attentively, without being struck with the truth of the views they contain, and the light they throw upon many facts in regard to the action of 'mineral waters, which have hitherto remained unexplained. We have always considered the change of air, temperate regimen, freedom from care, and pleasant society, to which the advantage of residence at our various watering places has been ascribed, as inadequate to explain the effects of the waters, compared with the ingredients obtained by analysis, especially when we consider that these effects were, to a certain degree, obtained by the waters bottled, carried to a distance, and used without any of these subsidiary aids. But now, when we see that these very ingredients, which were considered as the most inert, are converted, by Dr Murray's discernment, into the most active, the cloud which veiled our conception is removed, and everything seems so plain and simple, that we only wonder that it ever escaped observation.

Dr Murray's view of the composition of mineral waters does not diminish the value of those analyses which have been accurately made; but it will require them to be subjected to such a calculation, as he has exemplified in several instances, in order to have a clear view of their constituents. It has, however, occurred to us, that the best tabular form of the composition of mineral waters would be to state the quantity of each ingredient separately, as if they existed in simultaneous combination, thus:

Carbonic acid gas.

Carbonic acid.
Sulphuric acid.

Muriatic acid.

PART II.

CRITICAL ANALYSIS.

I.

A Treatise on the Diseases of Arteries and Veins, containing the Pathology and Treatment of Aneurisms and Wounded Arteries. By JOSEPH HODGSON, Member of the Royal College of Surgeons, London. London, 1815. 8vo, pp. 603.

Engravings intended to illustrate some of the Diseases of Arteries, accompanied with Explanations. By JOSEPH HODGSON, Member of the Royal College of Surgeons, London. Folio, 1815.

THE HE Royal College of Surgeons in London proposed, as the subject of the Jacksonian Prize for the year 1811, "Wounds and Diseases of Arteries and Veins." There was much propriety in the selection of this most interesting subject; for there is not, perhaps, any other in which the superiority of modern surgery stands more highly displayed; and certainly there is no one in which the skill, enterprise, and science of British surgeons have been more successfully exerted than this. Indeed, we hardly know anything more brilliant in the history of surgery, than the improvements which have been made, in our own days, by British surgeons, on the operations and treatment of a neurisms, and of wounded arteries. So lately as when we first began our studies, surgeons still hesitated to tie up the main trunk of an artery in the extremities,-and when the necessary attempt proved successful, instead of reckoning their success a thing of course, and referable to the wise and almost unerring provision which nature had made for continuing the circulation in the limb, by the collateral and anastomising vessels, they con

jectured only the existence of a lusus, or higher division of the arterial trunk.

Of the causes of secondary hæmorrhage, of the process of nature in the cure of opened arteries, and of the effect of the ligature which they daily used, their conceptions were still crude and im perfect. We have, not long since, known tapes nearly an inch broad applied to the artery in aneurism, in the fear that such ligatures as the surgeon trusted to in his ordinary operations, should cut and ulcerate the vessel; not to speak of the serre arteres, and other ingenious pieces of mechanism for keeping the sides of an artery in compressed and flattened apposition, with which the French and Italian surgeons are still amusing themselves.

The British surgeon now knows so well the powers and resources of nature, that there is not an arterial trunk within his reach that he has hesitated to tie; and he has thus successfully thrown a slight and single ligature round the femoral, the carotid, the external, and even the internal iliac artery. He knows now, that a large, broad, and flattened ligature is the worst, precisely for that reason, on account of which it had been thought the best and most secure; and that one of the reasons, for which he now employs a small thread, is to cut and wound the artery, he was formerly so anxious to save. He has ascertained, that, by this division of the internal coats of the artery, it becomes permanently closed and cicatrized by adhesive inflammation; that everything which interferes with this process, and which, instead of it, has a tendency to produce the suppurative or ulcerative inflammation, becomes a cause of secondary hæmorrhage; and, therefore, that the vessel must be separated as little as possible from its attachments; that no foreign body must be interposed for greater security; that the ligature itself should be small, that it may, as a foreign body, offend the least possible; he cuts off one end of it to lessen its bulk still farther; he has even risked cutting away both ends close to the knot, and closing the external wound over it; and he has talked of removing the entire ligature almost as soon as he has tied it, believing that its principal use has been effected when it has divided the coats of the artery, and produced in them a disposition to adhesion. Lastly, instead of slitting open the aneurismal tumour, as was the general practice little more than twenty years ago, he simply secures the artery at some distance above the tumour, and the direct impulse of the circulation being thus interrupted, he trusts to the establishment of a new and devious circulation, and to the consequent condensation and absorption of the aneurismal contents. To all these improvements, British surgery has almost an exclusive claim; and the