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Remarks on the Rev. Rowland Hill's Journal, &c. in a Letter to

the Author : including Reflections on Itinerant and Lay Preaching .

By John Jamieson, D. D. &c. 8vo. Is. Ogle. A Plia for Union, and for a free Propagation of the Gospel. Being ar Answer to Dr. Jamieson's Remarks on the late Tour of the Rev. R. Hill. Addrejtent to the Sects' Society for propagating the GoSpel, at Home. By Rowland Hill, A, M. &c. 8vo. 15. Wil-. liams. 1800.

These two pamphlets originated from some animadversions made by Mr. Rowland Hill, in his tour through Scotland, on the disci. pline and various fects of the Scotill church. Dr. Jamieson enters into an elaborate refutation of the strictures of the reverend tourist, who recriminates, at equal length, with many additional and severe reflections on the bignted and hostile divisions of the kirk. Some instances are given which seem to favour the accusation ; but it can be of little importance for us to state our opinion of the inerits of such a controversy. The Sacred Hifory of the Life of Jefus Christ, illuftrative of the Har

mony of the Four Evangelijis. To which is added, an Index of parallel Palliages. By the Rev. Thomas Harwood. Svo. 35. Cadell and Davies.

This is an attempt to give, in the order of time, the events of our Saviour's life, as related by the four evangelists. It is intended chiefly for young persons, to whom, however, we would recommend, in preference, the perusal of the gospel of St. Luke, and a subsequent comparison of the accounts of the other evangelists, with that writer's narrative. We met with a strange tale in this book, which we were surprised to see admitted on so weak an authority. After our Saviour was dead, one, named Longinus, a man of wealth and honour, and a member of the Sanhedrim, by an imper· tinent cruelty, pierced his fide to the heart with a spear, from which blood and water issued.' The name of this spearman is not mentioned by the evangelist; and it is not probable that any person of the name of Longinus was member of the Sanhedrim in our Sa. viour's time. Our author should at least have invented a Hebrew name to suit his purpose. The next thought is equally puerile. « The matter of the two facraments, which he instituted wben alive, flowed from him when dead, as the last memorial of his love to his church.

CRITICAL REVIEW.

OCTOBER, 1800.

Philosophical Transactions of the Royal Society of London. For

the Year 1800. Part I. 410. 145. feued. Elmlly and Bremner. 1800.

1. THE Croonian Lecture. On the Structure and Uses of the Membrana Tympani of the Ear. By Everard Home,

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The great object of this paper is to communicate a discovery respecting the nature of the membrana tympani; yet we cannot afsign to it a very high value, as the principal consequence drawn from it feems, from a subsequent paper, to be fallacious. The tympanumn has been usually considered as a membrane, but our author examining it in the clephant has found it fibrous, the fibres converging from the circumference to the centre, where the tympanum is united to the handle of the malleus. It is a little fingular, that he has not noticed the cphelion from the Eustachian tube, and a similar membrane from the meatus externus over the proper inembrane, on each surface, and that where he could not naturally distinguish fibres, he had not attempted to condense them hy heat. Ic may be admitted, however, that the drum of the ear is fibrous and muscular, without any central tendon, and with its due proportion of vefrels; but it is not easy to say what should be the consequence. The action of these fibres will undoubtedly straighten the membrane, and make it more sensible. This acrion may aid that of the muscles of the malleus, but will not superlede their use. In the following account of the utility of these fibres, our author apparently confounds the influence of the muscles of the malleus with the contraction of the fibril ra. diations.

From the explanation given of the adjustment of the membrana tympani, the difference between a musical ear and one which is too imperfect to distinguish the different notes in music, will appear to arise entirely from the greater or less nicety with which the muscle of the malleus renders the membrane capable of being truly adjusted. If the tension be perfect, all the variationis produced by

Crit. Rev. Vol. XXX. October, 1800.

the action of the radiated muscle will be equally correct, and the ear truly musical; but, if the first adjustment is imperfect, althoughı the actions of the radiated muscle may still produce infinite variations, none of them will be correct : the effect, in this respect, will be similar to that produced by playing upon a musical instrument which is not in tune. The hearing of articulate founds requires lefs nicety in the adjustment, than of inarticulate or musical ones : an ear may therefore be able to perceive the one, although it is not fitted to receive distinct perceptions from the other.

• The nicety or correctness of a musical ear being the result of mufcular action, renders it, in part, an acquirement; for, although the original formation of these muscles in some ears renders them more capable of arriving at this perfection in their action, early cultivation is still necessary for that purpose; and it is found that an ear, which upon the first trials seemed unfit to receive accurate perceptions of sounds, thall, by early and constant application, be rendered tolerably correct, but never can attain excellence. There are organs of hearing in which the parts are fo nicely adjusted to one another, as to render them capable of a degree of correctness in hearing sounds which appears preternatural.

Children who during their infancy are much in the society of musical performers, will be naturally induced to attend more to inarticulate founds than articulate ones, and by these means acquire a correct ear, which, after listening for two or three years to articu a late sounds only, would have been attained with more difficulty.

• This mode of adapting the ear to different sounds, appears to be one of the most beautiful applications of muscles in the body; the mechanism is fo simple, and the variety of effects so great.

Several ways in which the correctness of hearing is affected by the wrong actions of the muscles of the tympanum, that appeared to be inexplicable, can be readily accounted for, now that the means by which the membrane adjusts itself are underftood.' P. 12.

We must confess that the whole of this reasoning will suit as well the action of the muscles of the malleus as of the fibres of the drum; but our author's cases, which we cannot tranfcribe, are curious and well explained, though they might be equally fo on the common system. It is fingular that he has overlooked the use of the cochlea, which is filled with water, while it is now known that water is an infinitely better mea

dium of found than air. Fishes have it not, because the im- pression is conveyed through water: birds have it, because the

Tensibility of the ear is kept constantly on the extreme, by the handle of the malleus forcing the tympanum to a convex form.

The notes adapted for birds, and consequently their own notes, must therefore be acute, their compass limited, and their intervals Small. In the elephant, which hears most sensibly, all the parts are large and perfect, and the organ of hearing extends beyond the cochleæ, between the tables of the skull communicating from each side. Thus the head is all ear, as in birds the hollow part of the offeous system is a part of the lungs. On the whole, though we think our author's system unfounded, his paper is extremely valuable, as a collection of facts relating to the ear in man and various animals. We must, however, now step forward to

• Art. VIII. Observations on the Effects which take Place from the Destruction of the Membrana 'Tympani of the Ear. By Mr. Astley Cooper. In a Letter to Everard Home, Esq. F. R. S. by whom fome Remarks are added.'

In the instance related by Mr. Cooper, the gentleman who had a defect of the tympanum on one side, and the membrane or muscle incomplete on the other, had a correct musical ear, played with accuracy and taste, and sung in tune. The only defect was, that he could hear at only about twothirds of the usual distance. He felt also the sensation of the " teeth being on edge,' which has been attributed to the vicinity of the chorda tympani, but which Mr. Cooper attri.. butes, with more reason, to the effect of sounds on the nerve lining the labyrinth of the ear, which would convey the impreffion to the portio dura of the same nerve, and of course to the teeth. Yet there is a little ambiguity on this subject. Haller has said, that those in whom the tympanum is broken are at first hard of hearing, and afterwards become deaf. This is not consonant to the usual effects of deprivations; for nature rather exerts accessory motions to supply the deficiency, as in the case before us, where the external car became moveable ; and we remember an observation of Dr. Monro on the scholars of Mr. Braidwood's academy for teaching the deaf and dumb, that in every one examined by him, there were scarcely any traces of the membrana tympani. We think, therefore, with our author, that, in Haller's cxperiments, the injury was carried farther; and, in Mr. Braidwood's scholars, there may have been other defects, besides the absence of the tympanum. Perhaps, as Mr. Cooper alleges, the drum may be designed to modulate, rather than convey sounds, and, when absent, its use may be supplied by the fenestra ovalis and rotunda. It is remarkable, that Mr. Home, in his observations on this paper, does not notice the accurately musical ear which Mr. Cooper's friend possessed.

II. On the Method of determining, from the real Probabilities of Life,' the Values of Contingent Reversions in 'which three Lives are involved in the Survivorship. By Wile lian Morgan, Erg, F. R. S.'

This is connected with former papers · On Contingent Reversions, and is incapable of abridgement.

; III. Abstract of a Register of the Barometer, Thermometer, and Rain, at Lyndon, in Rutland, for the Year 1798. By Thomas Barker, Eig.'

The barometer ranged from 30.19, its height in February, to 28.21, which occurred in November; the thermomiefer from 840 to 51. But we fec evidently the effects of reflected heat in the afternoon observations, and the very low point in December was but for a short time; the next lowest was izo, . The inean heat of April was 51°2; the rain was 21.935. , • IV. On the Power of penetrating into Space by Telescopes; with a comparative Determination of the Extent of that Power in natural Vision, and in Telescopes of various Sizes and Constructions; illustrated by select Observations, By William Herschel, LL. D. F. R. S.'

This is a paper of singular curiofiev, truly carrying us bevond this visible diurnal sphere. We inust, however, first except against the conclufioul from our author's experiment, that light is tranfparent. The successive candles only pievented the rays froin the first being lost, and thus rendered their

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It is difficult to separate our author's reasoning from his algebraical language, yet we shall endeavour to do it, thougii, jy rendering his observations more intelligible, we may lose fomewhat of their extraordinary accuracy. Optical writers have proved that an object is equally bright at all distances.

This, our author properly observes, is true only of its • intrinsic' brightness, not of its absolute' brightness, or the ab. solute quantity of light emitted ; for, as he remarks, the sun to an obierver in Saturn is intrinsically as bright as to us, but it appears 100 times less, and is therefore 100 times less absolutely bright. This distinction must be kept in view through the whole paper. The same holds good in stars: their absolute brightness is in the inverse ratio of the squares of their distance, so that stars which are seven or eight times farther from us than Sirius, cannot be seen by the naked eye, and this is confirmed by observation.

It is surprising that we should fee reflected light at the difance of the Georgium Sidus, which is 18co millions of iniles, when, by distance and reflection, it must be 368 vines less inteule than with us; but self-luminous bødies are seen at a much greater distance ; for the nearest fixed ftar is more than 200,000 tiines farther from 'us than the fijn. If we fuppofc the stars of the second magnitude ar twice the distance of those of the firit, the difference of liglit appears, by algebraical analysis, not proportionally. leís. Thus the difference between

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