LAPLACE, PIERRE-SIMON. 



LAPLACE, PIERRE-SIMON. 



Motion of Jupiter'* Satellite*, independent of the Eicentricitie* ud 

 luclinstioui of tb Orbit* ; chap. 3, On the Inequalities of the Motiou 

 of the Satellite*, depending ou the Excentricitie* of the OrbiU ; ohap. 

 4, On the Inequalities of the Motion of the Satellite* in Latitude ; 

 chap. 5, Ou tlie Inequalities depending on the Square* and Product* i 

 of the Exoentricitie* and Inclination* of the Orbit*; chap. 6, On the 

 Inequalitie* depending on the Square of the Disturbing Force ; chap. 

 8, the Mcond (misprint), Numerical value* of the preceding inequalities; 

 chap. 7, On the Duration of the Eclipses of the Satellite* ; chap. 8, 

 Determination of the Mat*M of the Satellite*, and of the ObUtenees 

 of Jupiter; chap. 9, On the Ezcentricitie* and Inclination* of the 

 Orbit* of the Satellite* ; chap. 10, On the Libration of the Three First 

 Satellite* of Jupiter; chap. 11, Theory of the Fourth Satellite; ohap. 

 12, Theory of the Third Satellite; ohap. 13, Theory of the Second 

 Satellite; chap. 14, Theory of the Firot Satellite; chap. IS, On the 

 Duration of the Eclipse* of the Satellites, containing the comparison 

 with observation; chap. 16, On the Satellite* of Saturn ; 17, On the 

 Satellites of Uranus. 



BOOK IX. Theory of domett. Chap. 1, Theory of tlie Perturbation 

 of Comet*; chap. 2, On the Perturbations of a Comet when it 

 approaches very near a Planet ; ohap. 8, On the Action of Comet* on 

 Plineta, and on the Mass-'* of Comet*. 



BOOK X. On Variant Pointt of Ike Syttetn of tie Universe. Chap. 1, 

 On Astronomical Refraction ; chap. 2, On Terrestrial Refraction ; 

 chap. 3, On the Extinction of the Light of Star* by the Atmosphere, 

 and on the Atmosphere of the Sun ; chap 4, On the Measurement of 

 Altitude* by the Barometer; chap. 5, On the Descent of Bodies which 

 fall from a treat height; chap. 6, On some Cases in which the Motion 

 of several Attracting Bodies can be rigorously obtaiued ; chap. 7, On 

 the Alterations which the Motion of Planet* or Comets may undergo 

 by the resistance of the media which they traverse, anil by the gradual 

 transmission of gravity ; chap. 8, Supplement to the Theories of 

 Jupiter, Saturn, and the Moon ; chap. 9, On the Masses of the Planets 

 and Satellites, and on Astronomical Tables. 



SUPPLEMENT TO BOOK X On Capillary Attraction. Section 1, 

 Theory of Capillary Attraction ; section 2, Comparison with experi- 

 ment. 



Jn vol. v. are contained 



BOOK XL On tlie Figure and Rotation of the Earth. Chap. 1, His- 

 torical Notice ; chap. 2, On the Figure of the Earth ; chap. 3, On 

 the Axis of Rotation of the Earth ; chap. 4, On the Temperature of 

 the Earth, and on the Diminution of the Length of the Day by its 

 cooling. 



BOOK XIL On the Attraction and Repultion of Spherei, and on the 

 Lavi of Equilibrium and Motion of Elastic Fluids. Chap. 1, Histo- 

 rical Notice ; chap. 2, On the Attraction of Spheres, and the Repul-ion 

 of Elastic Fluids; chap. 3, On the Velocity of Sound, the Motion of 

 Ela-tic Fluids, and on Aqueous Vapour. 



BOOK XIII. (> the OtnUationi of the Fluids which cover the Planets. 

 Chap. 1, Historical Notice, especially on the Tides ; chap. 2, New 

 Researches on the Tides ; chap. 3, Comparison with observations, as 

 to the Heights of Tides ; chap. 4, Comparison with observations, as 

 to the Times and Intervals of High Water ; chap. 5, On the Partial 

 Tides of which the period is about a day ; chap. 6, On the Partial 

 Tides which depend on the fourth inverse power of the MOOU'B Dis- 

 tance ; chap. 7, On the Tides of the Atmosphere. 



BOOK XIV. On the Motion of the Celestial Bodies about their Centres 

 of Gravity. Chap. 1, Historical Notice of and Formulae on the Pre- 

 cession of the Equinoxes ; chap. 2, Historical Notice of and Remarks 

 on the Libration of the Moon ; chap. 3, Historical Notice of the King 

 of Saturn. 



BOOK XV. On the Motion of the Planets and Cornel*. Chap. 1, His- 

 torical Notice; chap. 2, Considerations supplemental to the second 

 book On the Variation of Elements; on the Development of the 

 Mutual Distance of Two Planets ; on the Great Inequality of Jupiter 

 aud Saturn; on the Determination of the Orbits of Comets by 

 observation. 



BOOK XVI. On the Motion of Satellites. Chap. I, On the Motion of 

 theMoon Historical Notice; chap. 2, On the Lunar Theory of Newton; 

 ehap. 3, On a Lunar Inequality of loug period depending on the Differ- 

 eeoe of the Two Terrestrial Hemispheres, aud also on those depending 

 on the Elliptic part of the Earth's Radius ; chap 4, On the Law ol 

 Universal Attraction; chap. 5, Ou the Motion of the Satellites of 

 Jupiter Historical Notice; chap. 6, On the Influence of the Great 

 Inequalities of Jupiter on the Motion of his Satellites ; chap. 7, On the 

 Satellite* of Saturn and Uranus. 



SBCOHO SUPPLEMENT (the first follows the tenth book). An extended 

 Tli' ory of Capillary Attraction (no date). 



THIRD (and posthumous) SUPPLEMENT (1827). On the Development 

 of the Distance of Two Planets, aud of it* Elliptic Co-ordinate* ; On 

 the Tides of the Atmosphere. 



We hare spoken freely of the defect* of Laplace's character, both 

 political and scientific, and it is now our more pleasing task to say a 

 few word* on the ' Mccanique Celeste,' a* a whole. We might dwell 

 upon the great discoveries, such a* those of the long inequality o! 

 Saturn and Jupiter, the cause of the acceleration of the moon's moan 

 motion, the explanation of the peculiarities iu the motion of J upitcr's 

 satellites, with a long train of similar achievement* ; but this, though 



the most common method of describing the character of a philosopher, 

 is not the tort of description which should be given of the ' Mocanique 

 Celeste.' Iu bulk is about 2000 quarto page*; and, owing to the 

 omission of all the *tep* which a good mathematician tnay be relied 

 on a* able to supply, it would, if expanded to the extent iu which 

 Euler would nave written the same mutter, have probably reached. 

 10,000 pages. If all this work had been collected by one man, even 

 from the writings of others, we should have called him the Delambre 

 of the theory of gravitation, and should hare priced his writings for 

 their extent, their faithful representation of the state of the science at 

 a particular time, aud the diligence displayed iu the undertaking. 

 When to the preceding, which is forgotten in the splendour of some 

 of the results, we add that to Laplace ia due the discovery of much, 

 ihe development of more, and that by the employment of his own 

 resources iu a manner which takes all the originality aud power of the 

 investigator, and the arrangement and combination of the whole, wo 

 may begin to see how he has earned his fame. 



There is moreover another consideration which applies to the author 

 of the ' Mccanique Celeste ' more than to any other, except that of the 

 ' Principia.' NVhen an investigator produces one result after another, 

 upon detached and unconnected subjects, we may feel admiration of 

 liis skill and sagacity ; but we can never know whether he followed a 

 route with the determination of overcoming a specific difficulty or not. 

 He His m where he succeeded, but not where he failed. It is other- 

 wise when an original writer attempts a complete system, at every 

 part of which he must work, and must show the world either a result 

 or a blank. It is seldom that Laplace leaves off at the stn- 

 with hU predecessors, though obliged, as just stated, to strive for 

 pre-eminence ou every single point. Had he consulted his own glory, 

 he would have taken core always to note exactly that p.irt of Lin own 

 work in which he had a forerunner ; aud it is not until this shall have 

 been well and precisely done, that his labours will receive their proper 

 appreciation. HU mathematical style u utterly destitute of the sym- 

 metry of that of Lagrange aud the simplicity ot' that of Euler, and he 

 is frequently even clumsy. He pays little attention to extreme 

 correctness of form. Upon fundamental principles, whether of 

 mechanics or analysis, he frequently needs a commentator, at least for 

 the student. 



Laplace explained his discoveries in a work entitled ' Exposition du 

 Systeme du Monde,' of which the fifth edition bears the date 1S24. 

 The account here given is in style and clearness of a superior kind, 

 somewhat too egotistical, aud partaking of the di-pos.tiou to suppression 

 already noticed. A similar companion to the ' Theory of Probabii 

 appeared as a preface to the work itself, and was published separately 

 (fifth edition, 1825), under the title of ' Essai Philosophique sur les 

 Probability's.' A little treatise, published iu 1S21, called ' Precis de 

 1'Histoire de I'Astronuniie,' afterwards was made the fifth book of the 

 fifth edition of the ' Systeme du Monde.' His lectures ou the 

 elementary branches of mathematics ore in the 'Lecous de 1'Ecolo 

 Normale.' 



Of the ' Thdorie des Probability ' we must speak precisely as of the 

 ' Mccanique Celeste,' adding perhaps that there is no part of the latter 

 in which more original power is displayed than iu the former. The 

 subject being somewhat isolated, its results are little known; they 

 have however been extensively applied to a-trouomy, both by Laplace 

 himself, and particularly by the German writers. 



The ' Mccanique Celeste ' was partly translated into English by a 

 learned American writer, Dr. Bowditch, whose death, though it pre- 

 vented his superintending the close of his work, did not take place till 

 the whole was ready for press. The, well-known work of Mrs. Somer- 

 ville is a selection from the ' Mocauique Celeste,' involving all the 

 fundamental parts of the theory of gravitation. The 'Systumo du 

 Monde' was translated by the late astronomer-royal, Mr. 1'oud. The 

 fundamental parts of the ' Theorits des Probability's ' will be found in 

 the ' Encyclopedia Metropolitans,' article ' Theory of Probabilities,' 

 by Mr. De Morgan ; and the method of using Laplace's results, with 

 no other knowledge than that of common arithmetic, iu the ' Essay 

 on Probabilities,' by the same author, in Dr. Larduers 'Cabinet 

 Cyclopicdia.' In the article on ' Probabilities ' in the ' Kucycloptcdiu 

 Britauuica ' the same results of analysis are treated. 



It is sometimes stated by English writers that Laplaco was an 

 atheist. We have attentively examined every passage which has been 

 brought iu proof of this assertion, aud we can tiud nothing which 

 makes either for or against such a supposition. It is easy, with an 

 hypothesis, to interpret passages of an author ; but wo are quite con- 

 vinced that a person reading Laplace for philosophical information 

 would meet with nothing which could either raise or solve a question 

 as to the writer's opinions ou the fundamental poiut of natural religion, 

 unless it had been put into his head to look. An attempt to explain 

 how the solar system might possibly have arisen from the cooliug of 

 a mass of fluid or vapour is called atheistical, because it attempts to 

 ascend one step iu the chain of causes : the ' 1'riucipia ' of Newton was 

 designated by the same term, and for a similar reason. What Laplace's 

 opinions were, wa do not know ; and it is not f.iir that a writer who, 

 at a time of perfect licence on such matters, has studiously avoided 

 entering on the subject, should be state*! of one opiniou or the other, 

 upon the authority of a few passage* of which it can only be said (as 

 it could equally be said of inoat mathematical works) that they might 



