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 Plea for Union, and for a free Propagation of the Gospel. Being an Answer to Dr. Jamieson's Remarks on the late Tour of the Rev. R. Hill. Addreffed to the Scots' Society for propagating the GoSpel, at Home. By Rowland Hill, A. M. &c. 8vo. Is. Williams. 1800.

Thefe two pamphlets originated from fome animadverfions made. by Mr. Rowland Hill, in his tour through Scotland, on the difcipline and various fects of the Scotifh church. Dr. Jamieson enters into an elaborate refutation of the ftrictures of the reverend tourist, who recriminates, at equal length, with many additional and fevere reflections on the bigoted and hoftile divifions of the kirk. Some inftances are given which seem to favour the accufation; but it can be of little importance for us to ftate our opinion of the merits of fuch a controversy.

The Sacred Hiftory of the Life of Jefus Chrift, illuftrative of the Harmony of the Four Evangelifs. To which is added, an Index of parallel Paffages. By the Rev. Thomas Harwood. 8vo. 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 evangelifts. It is intended chiefly for young perfons, to whom, however, we should recommend, in preference, the perufal of the gofpel of St. Luke, and a fubfequent comparison of the accounts of the other evangelists, with that writer's narrative. We met with a ftrange tale in this book, which we were surprised to see admitted on fo 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 impertinent cruelty, pierced his fide to the heart with a spear, from which blood and water iffued.' The name of this spearman is not mentioned by the evangelift; and it is not probable that any person of the name of Longinus was member of the Sanhedrim in our Saviour's time. Our author fhould at least have invented a Hebrew name to fuit his purpofe. The next thought is equally puerile. The matter of the two facraments, which he inftituted when alive, flowed from him when dead, as the last memorial of his love to his church.'

CRITICAL REVIEW.

OCTOBER, 1800.

Philofophical Tranfactions of the Royal Society of London. For the Year 1800. Part I. 4to. 14s. Jewed. Elmily and

Bremner. 1800.

I. THE Croonian Lecture. On the Structure and Ufes of the Membrana Tympani of the Ear. By Everard Home, Efq. F. R. S.'

The great object of this paper is to communicate a difcovery refpecting the nature of the membrana tympani; yet we cannot affign to it a very high value, as the principal confequence drawn from it feems, from a fubfequent paper, to be fallacious. The tympanum has been ufually confidered 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 ephelion from the Eustachian tube, and a fimilar membrane from the meatus externus over the proper membrane, on each furface, and that where he could not naturally diftinguish fibres, he had not attempted to condenfe them by heat. It may be admitted, however, that the drum of the ear is fibrous and mufcular, without any central tendon, and with its due proportion of veffels; but it is not eafy to fay what should be the confequence. The action of thefe fibres will undoubtedly ftraighten the membrane, and make it more fenfible. This action may aid that of the mufcles of the malleus, but will not fuperfede their ufe. In the following account of the utility of thefe fibres, our author apparently confounds the influence of the muscles of the malleus with the contraction of the fibril radiations.

From the explanation given of the adjustment of the membrana tympani, the difference between a musical ear and one which is too imperfect to diftinguish the different notes in music, will appear to arife entirely from the greater or lefs nicety with which the mufcle of the malleus renders the membrane capable of being truly adjusted. If the tenfion be perfect, all the variations produced by CRIT. REV. VOL. XXX. October, 1800.

K

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

The nicety or correctness of a mufical ear being the refult of mufcular action, renders it, in part, an acquirement; for, although the original formation of thefe mufcles in fome ears renders them more capable of arriving at this perfection in their action, early cultivation is ftill neceffary for that purpose; and it is found that an ear, which upon the first trials feemed unfit to receive accurate perceptions of founds, fhall, by early and conftant application, be rendered tolerably correct, but never can attain excellence. There are organs of hearing in which the parts are fo nicely adjufted to one another, as to render them capable of a degree of correctnefs in hearing founds which appears preternatural.

Children who during their infancy are much in the fociety of mufical 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 articulate founds only, would have been attained with more difficulty.

This mode of adapting the ear to different founds, appears to be one of the most beautiful applications of mufcles in the body; the mechanifm is fo fimple, and the variety of effects fo great.

Several ways in which the correctnefs of hearing is affected by` the wrong actions of the mufcles of the tympanum, that appeared to be inexplicable, can be readily accounted for, now that the means by which the membrane adjufts itfelf are understood.'

P. 12.

We must confefs that the whole of this reafoning will fuit as well the action of the mufcles of the malleus as of the fibres of the drum; but our author's cafes, which we cannot tranfcribe, are curious and well explained, though they might be equally fo on the common fyftem. It is fingular that he has overlooked the ufe of the cochlea, which is filled with water, while it is now known that water is an infinitely better medium of found than air. Fishes have it not, because the impreffion is conveyed through water: birds have it, becaufe the fenfibility of the ear is kept conftantly on the extreme, by the handle of the malleus forcing the tympanum to a convex form. The notes adapted for birds, and confequently their own notes, must therefore be acute, their compafs limited, and their intervals fmall. In the elephant, which hears moft fenfibly, 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 fide. Thus the head is all ear, as in birds the hollow part of the offeous fyftem is a part of the lungs. On the whole, though we think our author's fyftem unfounded, his paper is extremely valuable, as a collection of facts relating to the ear in man and various animals. We must, however, now ftep forward to

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

In the inftance related by Mr. Cooper, the gentleman who had a defect of the tympanum on one fide, and the membrane or muscle incomplete on the other, had a correct mufical ear, played with accuracy and tafte, and fung in tune. The only defect was, that he could hear at only about twothirds of the ufual diftance. He felt alfo the fenfation of the teeth being on edge,' which has been attributed to the vicinity of the chorda tympani, but which Mr. Cooper attributes, with more reafon, to the effect of founds on the nerve lining the labyrinth of the ear, which would convey the impreffion to the portio dura of the fame nerve, and of courfe to the teeth. Yet there is a little ambiguity on this fubject. Haller has faid, that thofe in whom the tympanum is broken are at firfl hard of hearing, and afterwards become deaf. This is not confonant to the ufual effects of deprivations; for nature rather exerts acceffory motions to fupply the deficiency, as in the cafe before us, where the external ear 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 experiments, the injury was carried farther; and, in Mr. Braidwood's fcholars, there may have been other defects, befides the abfence of the tympanum. Perhaps, as Mr. Cooper alleges, the drum may be defigned to modulate, rather than convey founds, and, when abfent, its ufe may be fupplied by the feneftra ovalis and rotunda. It is remarkable, that Mr. Home, in his obfervations on this paper, does not notice the accurately mufical ear which Mr. Cooper's friend poffeffed.

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 Wik liam Morgan, Efq, F. R, S.

6

This is connected with former papers On Contingent Reverfions, 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, Efq.'

The barometer ranged from 30.19, its height in February, to 28.21, which occurred in November; the thermometer from 84° to 51. But we fee evidently the effects of reflected heat in the afternoon obfervations, and the very low point in December was but for a fhort time; the next loweft was 13°.. The mean heat of April was 51°; the rain was 21.935.

IV. On the Power of penetrating into Space by Telefcopes; with a comparative Determination of the Extent of that Power in natural Vifion, and in Telefcopes of various Sizes and Conftructions; illuftrated by felect Obfervations. By William Herfchel, LL. D. F. R. S.'

This is a paper of fingular curiofity, truly carrying us beyond this vifible diurnal fphere.' We muft, however, first except against the conclufion from our author's experiment, that light is tranfparent. The fucceffive candles only prevented the rays from the first being soft, and thus rendered their effects more ftriking.

It is difficult to feparate our author's reafoning from his algebraical language, yet we fhall endeavour to do it, though, by rendering his obfervations more intelligible, we may lofe fomewhat of their extraordinary accuracy. Optical writers have proved that an object is equally bright at all diftances. This, our author properly obferves, is true only of its intrinfic' brightnefs, not of its abfolute' brightnefs, or the ab folute quantity of light emitted; for, as he remarks, the fun to an obferver in Saturn is intrinfically as bright as to us, but it appears 100 times lefs, and is therefore 100 times lefs abfolutely bright. This diftinction must be kept in view through the whole paper. The fame holds good in ftars: their abfolute brightnefs is in the inverfe ratio of the fquares of their distance, fo that ftars which are feven or eight times farther from us than Sirius, cannot be feen by the naked eye, and this is confirmed by obfervation.

It is furprifing that we fhould fee reflected light at the diflance of the Georgium Sidus, which is 18c0 millions of miles, when, by diftance and reflection, it must be 368 times lefs intenfe than with us; but felf-luminous bodies are seen at a much greater diftance; for the neareft fixed ftar is more than 400,000 times farther from us than the fin. If we suppose the ftars of the fecond magnitude at twice the diftance of thofe of the firft, the difference of light appears, by algebraical analyfis, not proportionally lefs. Thus the difference between