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1819.] of the Nean Density of the Earth.
7 rities in attraction, occasioned by pro- might be wished ; and a committee was tuberances and depressions on the sur- in consequence appoiu.ed, among whom face of a planet, will in some cases be were Dr. Maskelyne and Dr. Hutton, perceptible and appreciable: and hence “to consider of a proper hill on which it has been naturally inferred, that, where to try the experiment, and to prepare mountains are of a favourable magnitude, every thing necessary for carrying the shape, and position, their attraction may design into execution.” Mr. Charles actually be determined by experiment. Mason, (well known for his astronomical Newtou himself gave the first bint of tables,) and Mr. Smeaton, were among such an attempt in his “ System of the the most active in making the inquiry; World,” (Principiu, lib. 3,, where he and the latter, at length, informed the remarks, " that a mountain of an bemi- committee, that, in his opinion, Mount spherical figure, three miles high, and six Schehallien, one of the Grampian bilis in broad, will not, by its attraction, draw the north of Scotland, possessed the dethe plumb-line two minutes out of the sired properties in a very eminent deperpendicular.” In truth, the effect of gree; * being a very lofty and narrow its attraction would not exceed 1' 18".
ridge, very steep, extending a great The first actual attempt to determine length east and west, and very narrow the attraction of a mountain, was made from north to south." by the French academicians, who mea. Mount Schehallien being thus detersured three degrees of the meridian near mined upon, it became necessary to proQuito, in Peru, and wbu found Chim. vide for the expense of the undertaking, boraçı, . a very high mountare in that and to appoint duly qua thed persous to vicivity, to draw the plumb-lree 8" from conduct it. As to the expense, it was the vertical, by its actractionira This re- defrayed out of a surplus remaining from sult, however, fell far short Infohat the the benefaction of his Majesty, that ens ory might lead us to expech Said, there- abled Dr. Maskelyne to observe the fore, M. Buuquet expreseonstio wish that transit of Venus in 1769; and no filler the experiment might bree kinated in person could be wislied for to superinother places, and in nur pet murable tend the proceedings chan Dr. Maske circumstances.
lyne himself, provided he could obtain Nearly forty years after, namely, in leave of absence from the Royal Obserthe year 1772, 3, and 4, the confirmation vatory, for a sutficient time to take all that such an experiment properly con. the vicer and more delicate observations. ducted, would furnish to the theory of the “ This permission," says the Doctor, universal and mutual attraction of all“ his Majesty was graciously pleased to matter, was the subject of frequent dis- grant;" and, accordingly, the Astronoquisition arnong the tellows of the Royal mer Royal iminediately prepared for the Society of London, at their meetings; operations. He had two assistants, Mr. and it was at length determined, that an Reuben Burrow, who had previously been extensive experiment should be under assistant astronomer at Greenwich; and taken under the superintendence of a Mr. William Menzies, a land-surveyor person suitably qualified, both for the in Perthshire. These gentlemen meapurpose of ascertaming che etect of the sured all the lines, angles, elevations, allraction of a bill, and, if possible, of sections, &c. which were judged necesinferring from thence, the mean density sary; and Dr. Maskelyne made a few of of the earth. The first business was to the nicer astronomical observations, as fix upon a bill favourably situated for well as determined the deflection of the the purpose. Dr. Maskelyne, in a paper plummet from the vertical line, at conpublislied in the Phil. Transactions for venient stations, on both sides of the 1775, recommended two places which hill. This business being accomplished, he thought would be found very conve- he returned to Greenwich, and prepared nient; the one, on the confines of Lan, the general account of the imeasuremenis cashire and Yorkshire, where, within the and observations, which is inserted in compass of twenty miles, are four re- the Philosophical Transactions for 1775. markable hills, Pendle-bill, Pennyganit, From this memoir, in the Transaccions, Ingleborough, and Whernside; the other we learn that the sum of the deflections a valley, two miles broad, between the on both sides, occasioned by the attracWil Helwellin and Skiddaw, in Cumber- tion of Schiehallen, was 11":6. Dr. land. It was found, however, on closer Maskelyne adus, * The attraction of the examination, that neither of these loca- hill, computed in a rough manner, on hlies possessed all the advantages that supposition of its density being equal to
the mean density of the earth, and the deviation by the hill in comparison with force of attraction being inversely as the the perpendicular direction of gravity, square of the distances, comes out about which comparison of the computed and double this. Whence it should follow, observed effects, would give the ratio of that the density of the hill is about half the densities, namely, of the hill and the the mean density of the earth. But this earth. point cannot be properly settled till the “ The magnitude and novelty of these figure and dimensions of the hill have nice calculations, ihe requisite portion been calculated from the survey, and of science and ingenuity for making them Hence the attraction of the hill, found with effect, were such as appalled every from the calculation of several separate mind, and every one shrank from the parts of it, into which it is to be divided, task; when, at the request of the Prewhich will be a work of much time and sident and Council of tlle Society, I unJabour.” After this, Dr. Maskelyne dertook the performance; and after inpresents a few general corollaries; but cessant labour, during the course of a year, leaves the main difficulty to be sure produced the result of the whole, to the mounted, and the grand and much-looked. entire satisfaction of all the Society. for result to be presented, either by him. The account of these calculations was self or some otber person, at a future published in the Philosophical Transtime.
actions for the year 1778, and in volume The person who first effected this, xiv. of my Abridgment of these Transthen, is clearly entitled to the principal actions ; icand, though in a very conhonour arising from the solution of this densed 'I'm, occupied no less than a intricate and interesting problein. And hundrer Fanarto pages in that work, conthat this honour is due to Dr. Hutton, taining o is the results of many thousands and to bim alone, is evident from his of intric bsd alculations." elaborate paper published in the Philo Indee ingenuity called into exsophical Transactions for 1778. Such ercise in urse of those computaof your readers as have not an oppor- tions and is 5:21 bour requisite to carry tunity of consulting the Transactions, ther Editorlgh, are greaier than have will not be displeased to see the Doctor's been manifested by any one man, since own account of his labours, as given in the invention of logarithms, and the comthe 88th volume of the Philosophical putations that were required to ensure Magazine.
the utility of that admirable invention. « The next consideration was, whether The conclusion inferred by Dr. Hut. and how these observations and mea ton from the complete investigation, was, surements could be employed, in com- that the mean density of the whole mass parison with the magmitude and effects of the earth is to that of the mountain as of the whole globe of the earth, to deter. 9 to 5. Assuming this as the correct mine its mean density, in comparison ratin, and at the same time assuming with that of the mountain. This indeed the mean density of the hill as agreeing was the grand question, a point of the will that of common stone, or being highest importance to natural philosophy, about 24, the doctor by compounding ot" novel and of the most delicate and the two ratio's, obtained 4 to 1, for the intricate consideration, as well as a work ratio of the densities of the earth and of of immense labour. Here were to be rain water; and from the whole made calculated, mathematically, the exact this deduction : " Since then the mcan magnitude of the hill, its shape and density of the whole earth is about double form, in every respect, the position and that of the general matter near the suro situation of all its parts, the various ele- face, and within our reach, it follows, vations and repressions, and the attrac that there must be somewhere within the tion on the pluinmets, by every point earth, towurds the more central parts, and particle in the bill, as well as of the great quantities of metals, or such like neighbouring in:»untains on every side of dense 'inatter, to counterbalance the it. Then there was to be calculated, in lighter inaterials, and produce such a conlike manner, the altraciion of the whole siderable mean density.”—Phil. Trans. magnitude and mass of the earth, on the 1778. This notion, then, of the much same plunimets. La-ils, i la proportion greater density about the central regions of these twii compuied altractions was to of the earth, or indeed io nearly 1HOde compared with that of the observed thirds of the earth's diameter, was orie effects on the pluinucis, vit, the lateral ginally the suggestion of Dr. Hutton; M.
1813.) Mr. Lucas, in reply to an Anonymous Critic. 9 Cuvier, and many other persons, err his science, his labours, and investigain ascribing it to Dr. Maskelyne or to tions, ascribed, however unintention Mr. Cavendish.
ally, to another. I cannot conclude without remarking
OLINTHUS GREGORY. that, though Dr. Hutton had no reason Royal Military Academy, Woolwich, to doubt the accuracy of his computa
Dec. 14, 1812. tions, he expressed in the paper, from which I have last quoted, some doubts To the Editor of the Monthly Maguzine. as to the correctness of the assumption SIR, of the density of the hill, and pointed I has often aftreed to an anthor assaila
AM induced, by that liberality which out methods by which that assumption might be corrected. He went farther. ed by some bandit of literature, a small Feeling constantly a desire to give the space for defence and triumph, to ask finishing and correcting stroke to these the like favour for one, who knows not computations, I very well remeniber (exclusive of the advantageous respectahearing him, about nine or ten years ago, bility, independence, and great circu. urge the learned Mr. Professor Playfair, lation, of the Monthly Magazine) where of Edinburgh, either to make, or to pro. else to apply. I will strictly confine myo cure and communicate to him, such more self to his wretch's discomfiture, and accurate observations upon the geolo. my charge shall be single, clear, and cons gical structure of the hill, as would ena- cise-that, the British Critic's Review ble him to give the utmost precision to (in February 1812, which by chance I his results, of which they were suscep- heard of) of JosePs, a religious Poem, aible. From the information transmitted is False. by Mr. Playfair, the doctor infe..ed that The work is of considerable extent, the mean specific gravity of Schehallien and aims to embrace the whole of the is about 2.7 or 2.8, its constituent va- Jewish dispensation; the Pretace clearly rieties being reduced to three kinds, the defines the plan; yet the Reviewer, specific gravity of one heing 2.4, of ano. (what an incongruous name, and yet
it ther about 2:75, and some parts as high is the only one be ever dare own,) after as 3, and even 3.2. Thus, then, taking a few desultory remarks, 9.notes part 2.75 as the mean, he obtains f X 24 of a short speech, so as to destroy both tis. or almost 5, for the mean tien. sense and grammar, and then cries,sity of the whole mass of the earth; a “ Here certainly is no rival to Moses." result which was first given, I believe, Rival to Muses! I suppose then be by the doctor himself in part 55 of the reckons Million a successful rival-and New Abridgment of the Philosophical Louth likewise of Isaiah--and Klapstock Transactions, published in 1808, and and Cumberland victorious over' Male repeated in the re-publication of the thew, Mark, Luke, and Jolin! whole paper, in the second volume of But, in iny case, sir, it happens that his his 8vo, Tracts.
quotation is not even the paraphrase of a Professor Playsair has recently gone Mosean passage: it is Josepli's supposed over all che computations necessary to introductory account of himself to Poridetermine this point, de novo, making phar. Was the critic only ignorant that use of his own observations as to the there is no such scene in the Bible? I mineralogical constitution of the bill; know not: the false view of the work, and his results confirm, in a remarkable which he immediately adds, cannot so manner (see Phil. Transac. for 1811) easily be excused. “ Alterwards (con. the accuracy of the calculations and de- tinues this critic) we find bim writing ductions made by Dr. Hutton,
what Moses, without a very extraordia I have dwelt longer upon this subject nary gift of prophecy, could not have than might otherwise have been neces written; and, it may reasonably be sary, in order that here, as well as upon doubted, whether he would if he could." other topics, “ llonour should be given He then quotes three lines, chiefly names where honour is due." One of the of modern missionaries. Now, sir, I strongest incitements to men of science beg leave to ask, does not this critique is, “ihe quiet and peaceable possession" (without further troubling you or your of the fame accruing from their inven. readers) draw the direct inference that I tions and discoveries; and one of the speak in the name of Moses, or of some greatest mortifications to which a man of person of that period, or that I have virtue and ingenuity can be subjected, made a prophetical attempt, ur, at least, must be to see the result of his learning, been guilty of an anachronism? It is MONTILY MAG. Nu, 237.
neither of the cases, sir, but a plain sitive et negative d'ou coulent presque apostrophe in my own character to the tous les maur de la vie sociale." missionaries; and,'out of iny respect for Before I otler any reoiarks on these their labours, I introduce their names, sentiments, I would preinise that, in all though of different churches, and “ 1100 probabiliiy, and from what we have formed for metre."
lately seen and heard, the science of It is remarked in the Preface, " critics education is yet in its infancy; and that not only condemn an author for what he the way in which it has been conducted has and has not done, but for what in Europe for many centuries, is not ibat he does not proiess or wish to do.” which is calculated to produce the best These reviewers, I truse I have shown; and most permanent impression upon the go beyond this strong accusation, and human mind. I am the inore willing to falsely insinuate that I do that, which I enter into a disquisition concerning ibe Deither directly nor indirectly have done, propriety of the stimulus of emulation in If it were to be asked, what could pos. our schools, from hasing observed, that ibly induce any writers su to commit a worthy friend of mine, whose writings themselves? I answer, that they are are well known and esteemed by the anonyinous, -that they have no idea I public, bas hinied, that such a feeling can rep'y to them,—and that their nar. ought to be discouraged ; now, although mw anit bigotted nutions are doubly of I may be disposed to allow a due weight fended; first, that in my Pretace I should to his opinion, yet we are not, I think, trent reviewers lightly-and, secondly, called upon to sacrifice our judgment that I, a clergyman of the Church of against the evidence of facts: it will be England, should write a work profeg. well therefore to examine a little into sediy religious, upin che broad basis of the nature of the case. Calinlic Christianity, and not to the If there be any truth in the doctrine of inclusive honour and praise of our own motives, of cause aud effect, of praise establishment, and to the anathema of and blame; and, if the human mind be all other.
governed by motives; if, from one end of To expose these inalaperts will nid, I ihe carth to the other, we constantly see hope, the cause of crery independent the same causes producing the same auihor, and gra:ily every reuder, who effects; and that, consequently, without has it mind ot bis own; and, -uill further motives, man cannot act at all; so, we In show their worthicssnese, I could re must admit, that the minds of children, fer to half a dozen other articles in the which are simply full-grown minds in game Review, which (I know not if will ininiature, must have some motive preare alike false, but one concerning lienry sented to them to stimulate them to exKirk Whileis,) are yet more illiberal, ri. ertio.). I say stimulate them to exerfling, and erroneous, ihan thit which tion: now, if emulation be taken away, has required an exposition from
what stimulus are we to apply in its drebury, Bills, CHARLES Lucas, place? “Aitacia pleasure to their learne Dec. 2,*1812.
ing," says St. Pierre: and so, munibus
pedibusque, say I: unil where will you be To the Editor of the Monthly diugazine. able to find any motive tu apply to the SIR,
human mind with more pleasure and N looking over the works of Bernar. force than emulation? The pleasure of ailention was arrerted by his l'ocva d'un lead to excellence; and I am of o;inion Solitaire ; and partichlarly boy se cu- that, as long as that feeling is not pressed titleet, Poeur pour une Education Nati co the injury or retardinion of viher boys, Onule. Amning some pertinent obser- (and bere only lies the difficulty, such as. väsimme the following, to which I am pirations to jame and texçıle ace ought Due disposed to assent; le previously ob to he encouraged: but I am ready to serves.' Thai emulation should be banished adinit, what il, instead of producing its from our schools. L'Iimulation: (-avs proper object, Emulation become a mei1g he) est la cause de la plupart des maur ol introducing envy, bickerings, and strite, ou genre humain. Elle est la rucine de
115 proper object is lost, and it becomes, Tambition ; car Icomulution produit le of course, a mischiet. llence, it is crią cesir d'eire le premier; et le désir d'utie dent, that the wcilling of this powertul le premier, n'est cuire chose que l'aide auxiliary requires mucho skill, and the bition, qui se purtuge, suivant les posin hami uf an wbie master; and here it will livigs at les chupucices, eu umbilions poo bene cessary that the master slould take
11 into the account the capacity of his pu- of men's being ambitious to outsie each pil his disposition for this or that par. Other in deeds of prowess, and, what is cicular study-the length of time it is falsely termed, military glory, let us intended he should pursue it; and, in. imagine men only ambitious to do good deed, a variety of et cetera to be known ambitious to excel one another in deeds only by application in individual cases, of charity, benevolence, and love-amwithout all which, much valuable time bitious to listen to that still small voice will be irrecoverably lost. But, says of wisdom, which at times is heard, even St. Pierre, “ Emulation is the root of by our heroes of blood-ambitious to asAmbition," and therefore it must be torn sist in the progression of intellect and the up! It is an unfortunate circumstance diffusion of truth; let us imagine, I say, for mankind, that Ambition is so often sucli ambition, and I am very much deused in a bad sense, and in a bad cause; ceived if it would not be accounted vira and to a benevolent mind, such as St. tuous, praiseworthy, and sublime. Pierre's appears to have heen, it is no If there be any truth in these reinarks, wonder that the only method which I think it will follow, that emulation struck him as desireable, was to eradicate and ambition, when applied to the pro80 base a passion as, in its worldly exem- gression of intellect, and the happiness plification it is, I am sorry to say, too and well-being of men, are qualities of Cormonly found to be. However, we the human inind by no means to be din must noi despair: St. Pierre might be spiserl or superseded :--that our rules mistaken; and so bave been myriads of for judging of the propriety of their ар, minds as benevolent as his. It is the plication are to be formed by the effects province of true philosophy not to at which the use of them produces, as in tempt to overturn, but to direct aright other moral qualities; that, where the the powers of the human mind: if, upon effects are bad, it is to be presumed that investigation, it should be found ihat the use of them is bad, as in war, colie Emulation, or, if you please, Ambition, quest, and desolation : that, where the be a part of our nature, as I am effects are good, as in instruction, bea inclined to think it is, the question nevoletice, and happiness, their assista will then he, not whether it should be ance is sanctified, and their induence eradicated or no, because if it be a part and use incontrovertibly gowd. of our nature, that cannot be done ; but,
JAMES JENNINGS, in what way may it be best directed Huntspill, Dec. 22, 1812. and that it may be directed both in youth
P.S. Your readers will oblige me by corand, mantiood, to the happiness and recting the following errors in my paper of well-being of inan, I entertain no shadow
your Magazine, for September last, page 10k, of doubt. Ii we could see this moral column 2, line 11, for were read ave-line quality of the human mind, this scare.
23, for propitious read monstrous-column 1, crow for the benevolent, the timid, and
line 38, for referred read deferredo the well-meaning; this powerful steamengine of intellect-employed only for To the Editor of the Monthly Maguzine, the welfare, the good, and the happiness, SIR, of mankind, how different would it then
T is not difficult to analyse the causes appear ! Instead of carrying fire and sword into the divellings of our neigh. societies of Men; but to expose errors hours—instead of laying waste a country, is dangerous, because, being engendered and rioting in the blood of our fellow by deep-rooted prejudices of education, creatures, let us imagine Ambition and forstered by self-interest, they are pruinpting mankind in the glorious career maintained by active a!!d vindicrive of truth, justice, and benevolence : in. Passions. stead of our exclaiming “ Bebold an
An experienced Philosopher expressAlexander, a Cæsar, a Charles the ed his apprehension of those pasTwelfth, or a Bonaparte;" imagine such sions and prejudices when, be declared, characters held up to our execration, or
That, if his band were full of Truths, le at least in our pity, and the heroes of would not open it!
Such an inperfect mercy, of peace, and of benevolences being is man-ihat Truth must always be sach men as Milton, as Jocke, or as
exhibited in a way calculated in humour, Howard, crowned with the laurels of and not to oppose, his prejudicesWisdom and of Peace, then may we hail those who are bardy enough to maintain Ambition with delight, as its deeds should it, must run the chance of being saclia shine furth as the morning! Instead ficed to their temerity!