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Herschel's paper might as well have been omitted; for the observations have no tendency to increase our knowledge of the physical constitution of the planet, or of the nature of light; and both Dr. H. and his Hampstead friend are convinced the appearance was an illusion

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XIII. Hydraulic Investigations, subservient to an intended Croonian Lecture on the Motion of the Blood. By Thomas Young, M. D. For. Sec. R.S. Read May 5, 1808.

Dr. Young, having lately fixed on the discussion of the nature of inflammation, for the subject of an academical exercise, found it necessary to examine attentively the mechanical principles of the circulation of the blood, and to investigate minutely and comprehensively the motion of fluids in pipes, as affected by friction, the resistance occasioned by flexure, the laws of the propagation of an impulse through the fluid contained in an elastic tube, the magnitude of a pulsation in different parts of a conical vessel, and the effect of a contraction advancing progressively through the length of a given canal. He here communicates to the Royal Society such results of his investigations as are mathematical, reserving the physiological results for another paper. The investigation. here described is too abstruse, and some of the tables too extensive, to be susceptible of abridgement, or to allow of our describing intelligibly in small compass the principles of the Dr.'s method: but we the less regret this on the present occasion, because, though we think Dr. Y. has simplified and improved some of the theorems of Dubuat, Gesner, and others, yet we are persuaded he has sometimes proceeded upon insufficient data, and reasoned from such a paucity of experiments as can never satisfy a genuine disciple of the great inductive philosophers. The inquiry is well conducted as far as it goes; but should, we think, have received accessions from a greater variety of experiments, before it had been suffered to meet the public eye; especially in what foreigners look upon as the grand depository of British science.

XIV. A Letter on the Alterations that have taken place in the Structure of Rocks, on the Surface of the basaltic Country in the Counties of Derry and Antrim. Addressed to Humphry Davy, Esq. Sec. R. S. By William Richardson, D.D. Read March 17, 1808.

This interesting communication, which occupies 36 pages, and is accompanied by 2 fine engravings, relates to the basaltic area which comprehends the greater part of the county of Antrim and the east side of Derry. In the periphery of this area, and especially at the northern side, the basaltic appearances are extremely striking, the perpendicular façades often continuing for miles, and every separate stratum being com

pletely open for examination. Giant's causeway, and the organs, which lie in this region, have long attracted the notice of the curious; but these form a very small portion of the basaltic mass: there are many finer collections of pillars on the same promontory, and these not mere detached groups, but small parts of a grand and regular whole. Dr. Richardson here traces the progress of no less than sixteen strata which compose the promontory of Bengore; and then collects the principal facts likely to be useful in geological inquiries, as below:

1. Every stratum preserves accurately, or very nearly, the same thickness through its whole extent, with very few exceptions.

2. The upper and lower surface of each stratum preserve an exact parallelism, so long as they are covered by another stratum; but when any stratum becomes the superficial one, its upper surface is scolloped, or sloped away irregularly, while the plane forming its base continues steady, and rectilineal; but the parallelism of its planes is resumed as soon as another stratum is placed over it.

3. The superficial lines bounding the summit of our façades, and our surface itself, are unconnected with, and unaffected by, the arrangement of the strata below them.

4. Nature, in the formation of her arrangements, has never acted upon an extensive scale in our basaltic area, (at least on its northern side, where our continuous precipices enable us to determine the point with precision,) but changes her materials, or her arrangement, or both, every two or three miles, and often at much smaller intervals.

5. Wherever there is a change of material, as from one stratum to another in a vertical line; or where the change is in a horizontal direction by the introduction of a new system; or where a whyn dyke cuts through an accumulation of strata.; in all these cases the change is always per saltum and never per gradus; the lines of demarcation always distinct, and well defined; yet the different materials pass into each other without interrupting the solidity and continuity of the whole mass.

6. The façades on our coast are formed as it were by vertical planes, cutting down, occasionally, the accumulations of our strata; the upper part of these façades is generally perpendicular, the lower steep and precipitous.

7. The bases of our precipices commonly extend a considérable way into the sea; between the water and the foot of the precipice, (and especially near the latter) there is frequently exhibited the wildest and most irregular scene of confusion, by careless observers supposed to be formed by the ruins of the precipice above, which have fallen down; such, no doubt, was Mr. WHITEHURST's idea, when he describes one of these scenes as "an awful wreck of the terraqueous globe."

But a more attentive observer will soon discover that these capricious irregularities, whether in the form of rude cones, as at Beanyn Daana, and the west side of Pleskin; or towers, as at the dyke of Port Cooan and Castro Levit, at the foot of Magilligan façade, even spires and obelisks, as to the westward of Kenbaan, and at the Bull of Rathlin; yet all of these once formed part of the original mass of coast, stratified like it, and VOL. V.

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their strata still correspond in material and inclination with those in the contiguous precipice.

8. These vertical sections or abruptions of our strata are by no means confined to the steeps that line our coast; the remaining boundary of our basaltic area has several of them equally grand; and similar abruptions, or sections (though not so deep) are scattered over a great part of our area, and especially on the ridges of our hills and mountains which are cut down in many places like a stair, by the sudden abruption of the basaltic

stratum.

9. Wherever the strata are thus suddenly cut off, whether it be a mass of accumulated strata as in the façades on our coast, or solitary strata in the interior, the materials on one side of the abruption are completely carried away, without a fragment being left behind, while on its other side the untouched stratum remains intire and undisturbed.' pp. 201–203.

Dr. Richardson then enters much at large into theoretical considerations suggested by his examination. He shews that there are phænomena which cannot be reconciled to the theories of Buffon, Playfair, and others; and then makes these general inferences :

• That the hills and mountains, in the district I have been describing, were not raised up or formed as they now stand, but that they are the undisturbed remains of strata that were left behind, when stupendous operations carried away the parts that were once contiguous to them.

That the inequalities of this surface were all produced by causes acting from above, and carrying off whatever they touched, without in the least disturbing what was left behind.' p. 217.

The Doctor does not, however, acquiesce in the opinion, that these external irregularities could be produced by the agitation of superincumbent waters while they covered the earth the sudden and vertical abruptions could never, he says, be produced by any such agitation.

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We cannot quit this paper without noticing our Doctor of Divinity's use of the word nature: as if unwilling to offend the fastidious ears of the modern lovers of wisdom' by mentioning the name of the Supreme Being, as the Great First Cause, he says, "By the word nature, which frequently occurs in the course of this memoir, I always mean, according to Ray's defi nition, the wisdom of God in the creation of the world." We shall not quarrel with this definition, in this place, though we are sure it does not agree with any one of the meanings given in Aristotle's elaborate chapter on the various acceptations of the Greek word Quis; and though we are equally certain, that the notion of the poet was more correct and philosophical, who said,

Nature is but a name for an effect,
Whose cause is God.'

sages.

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But we would wish Dr. R. to try the effect of substituting his explication for the word itself, in some of his own pasFor example: The wisdom of God in the creation of the world, has been very kind, in a geological point of view. Could Dr. R. mean to speak of geologically kind wisdom? Again: The wisdom of God in the creation of the world, has condescended occasionally to withdraw the veil, and lay herself open to view,' &c. Yet according to the Doctor's own account the veil was withdrawn long after the creation of the world. Such are specimens of the absurdities in which writers become involved, who are afraid of adopting the phraseology of consistent Theists, lest they should expose themselves to the suspicion of not being genuine philosophers!

XV. A Letter on the Differences in the Structure of Calculi, which arise from their being formed in different Parts of the urinary Passages; and on the Effects that are produced upon them, by the internal Use of solvent Medicines: from Mr. William Brande to Everard Home, Esq. F. R.S. Read May 19,

1808.

Brande's Paper on Calculi.
Read May 19, 1808.

XVI. Some Observations on Mr. By Everard Home, Esq. F. R. S. Mr. Brande, in the first of these papers, describes the re sults of a chemical examination of the calculi contained in the Hunterian Museum. He treats his subject under the headsof calculi formed in the kidneys, and voided without having afterwards undergone any change in the urinary passages,--of calculi which have been retained in the kidneys, of calculi of the urinary bladders,―of calculi of the urethra,-of calculi from other animals than man, as from the horse, the ox, the sheep, the rhinoceros, the dog, the hog, the rabbit. From these examinations it appears, that calculi formed in the kidneys, and immediately voided, are almost always composed of uric acid; and that the phosphates are very frequent ingredients in calculi of the bladder, more especially in those, which, from their situation, have been exposed to a continual current of urine: they also are uniformly deposited upon extraneous substances introduced into the bladder, but appear never to form small kidney calculi. Mr. Brande next inquires into the action of solvents; which are of two kinds, alkaline and acid. The following are extracts from his conclusions:

It may therefore be asserted, that although alkaline medicines often tend to diminish the quantity of uric acid, and thus to prevent the addition of that substance in its pure state, to a calculus in the bladder; they favour the deposition of the phosphates.

It cannot be doubted that the alkalies reach the bladder, since in cases

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where large doses of sub-carbonate of potash have been exhibited, I have

seen evident traces of it in the urine.

Where the phosphates only are voided, it has been proposed to dissolve the calculus by the exhibition of acids, and more especially the muriatic acid.

During the use of the muriatic acid, the phosphates are either diminished or disappear altogether; and even sometimes the urine acquires an additional acidity: a solution of that part of the calculus which consists of the phosphates might therefore be expected; but even then the nucleus of uric acid, would remain, and thus a great deal of time would be lost without any permanent advantage.

I have also occasionally remarked, that during the use of acids, the uric acid re-appears, and even seems to be augmented in quantity.

It has been shewn that in the majority of cases, the nuclei of calculi originate in the kidnies, and that of these nuclei by far the greater number consist of uric acid; the good effects therefore so frequently observed during the use of an alkali, arise, not from any actual solution of calculous matter, but from the power which it possesses of diminishing the secretion of uric acid, and thus preventing the enlargement of the calculus, so that, while of a very small form, it may be voided by the urethra.” pp. 241-243.

Mr. Home's paper contains an account of some cases which confirm Mr. Brande's observations. We recommend both memoirs to the serious attention of such professional men, as are not yet thoroughly convinced of the great advantages derivable from chemistry in ascertaining the nature, prevention, and cure, of various maladies.

XVII. On the Changes produced in Atmospheric Air, and Oxygen Gas, by Respiration. By W. Allen, Esq. F. R. S. and W. H. Pepys, Esq. F. R.S. Read June 16, 1808.

The process of respiration being essential to the continuance of life, every investigation connected with it assumes peculiar importance. Most former experiments relative to this subject have been attended with errors, the principal of which were here prevented by the magnitude of the instruments employed. Messrs. Allen and Pepys's experiments were made with a water gasometer capable of holding 4200 cubic inches of gas; to which were annexed two mercurial gasometers, each containing about 300 cubic inches, and connected with jars standing in a mercurial trough, in order that small portions of the expired air might be saved, and examined at suitable times.

The number of experiments described here is eighteen, in which the breathing was as nearly natural as possible; the pulse was not raised more than one beat in a minute, although the respirations were deeper and fewer than in the open air; being about 58 in 11 minutes, instead of 19 in a minute, the usual rate of respiration in the same subject. It appears

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