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CHARLES HUTTON, Esq. LL.D. F.R.S.

Professor of Mathematics

In the Royal Military Academy, Woolwich:

In Testimony

Of Admiration and Esteem

For the eminent Talents and Genius

He has so frequently and usefully displayed

In his public Capacity;"

And for those generous and amiable Qualities

IVhich shed a Lustre over the Path

Of private Life;

The following Sheets are inscribed,

By his

Affectionate Friend, and obliged Sercant,

THE AUTHOUR.

PREFACE.

WHEN an authour ushers a performance into the world

on a subject that has been frequently treated upon, and often with considerable ability and success, it is natural for him to frame an apology for his undertaking, either by writing a panegyric upon the subject he attempts to discuss, or by pointing out those particulars in which his own work differs from others, and shewing how far there is a probability that his deviations from the usual modes of arrangement, or discussion, will be productive of advantage. The subject of the treatise now presented to the public, is ASTRONOMY, a science which needs no laboured eulogium; for its intrinsic excellence, and its attendant advantages, are such, that it has been studied, encouraged, and promoted, by the most learned and eminent men of all ages and all countries. Astronomy not only contributes to the improvement and perfection of Chronology, Geography, and Navigation, to the extension of Trade and Commerce, and the consequent comfort of life; but it is also of admirable use, in strengthening the mind by proper exercises, in arming the reason against the vanity of scepticism and the delusions of sophistry, and in adding fresh power to the native force and penetration of the understanding. Besides these benefits, which all are willing to ascribe to Astronomy, there are others which are not so universally acknowledged, yet ought not to be neglected or forgotten-this most delightful, this noblest of the sciences, subjects, as it were, the economy of the universe to our contemplation it enables us to obtain a nearer acquaintance with the most numerous, the most stupendous and magnificent scenes in the whole creation; to trace out their mutual intercourses, their certain and determined motions, their regular returns, their stated periods; to discover the inviolable laws which regulate the heavens, and the admirable harmony which pervades the universe: and while we are thus engaged,

while we are permitted "to scale the etherial towers, and "freely range through the celestial fields," is it possible that we should not be impressed with a sense of the unlimited power, unbounded wisdom, and infinite goodness, of the adorable Creator and Governour? The great excellence of Astronomy then, even as a promoter of morality and devotion, must be admitted, if it appear that it furnishes us with stronger arguments to prove the existence of a supreme, intelligent First Cause-shews more effectually his power and wisdom-or gives us more clear and just notions of his other attributes and perfections, than any other knowledge which is attained by the mere light of nature: and that it accomplishes this, nay, more than this, cannot fairly be denied, since many, who are no mean judges in this respect, are constantly ready to assert it, on the fullest conviction. "If we," says the pious and learned Dr. Watts, "look upward with David to the worlds above us; if we consider the Heavens as the work of the finger of God, and the moon and the stars which he bath ordained; What amazing glories discover themselves to our sight? What wonders of wisdom are seen in the exact regularity of their revolutions? Nor was there ever any thing that has contributed to enlarge my apprehensions of the immense power of God, the magnificence of his creation, and his own transcendent grandeur, so much as that little portion of Astronomy which I have been able to attain. And I would not only recommend it to young students for the same purposes, but I would persuade all mankind (if it were possible), to gain some degree of acquaintance with the vastness, the distances, and the motions of the planetary worlds, on the same account. It gives an unknown enlargement to the understanding, and affords a divine entertainment to the soul and its better powers. With what pleasure and rich profit would men survey those astonishing spaces in which the planets revolve, the hugeness of their bulk, and the almost incredible swiftness of their motions? When we muse on these things, we may lose ourselves in holy wonder, and cry out with the Psalmist, "Lord, what is man, that thou art mindful of him; and the son of man, that thou shouldst visit bim ?"

Since, then, the science of Astronomy is so powerfully recommended to our attention and regard, by its tendency to improve the understanding, to delight the imagination, and to ameliorate the heart; it is no wonder that publications, in which its principles have been laid down, its elements demonstrated, or its phenomena explained, have become very

numerous.

The Authour of the present undertaking has no wish to depreciate the character of any of these publications, or to lower their claims upon general esteem, in order to induce the public to transfer their exclusive encouragement to his own performance; on the contrary, he cannot refrain from giving his suffrage to the real value and obvious utility of the labours of several of his predecessors in this department of science. The works of Mr. Bonnycastle, Mrs. Bryan, Mr. Ferguson, and Dr. Long, are admirably calculated to convey in a popular manner, but in a manner which often unites familiarity with elegance, a clear and correct statement of the various facts which Astronomy brings to light, and ingenious explanations of the principal phenomena of the Heavens. Among the scientific treatises, those of Dr. Gregory, M. de la Caille, and Mr. Professor Vince, merit distinguished approbation: Dr. Gregory's Elements of Astronomy, Physical and Geometrical, though published at a time when the physical principles of Newton were comparatively but little known, and where known, opposed, richly deserved the esteem in which they were held by Newton himself, as a most excellent explanation and defence of his philosophy: in almost every page they display strong traits of originality, and of ripened judgment, and will remain a lasting monument of the admirable genius and profound knowledge of their authour.-The Elements of Astronomy by M. de la Caille, have also been long admired, on account of the elegance, the accuracy, and the scientific skill with which they are exhibited and The complete System of Astronomy, by Mr. Vince, is generally and justly acknowledged to be the most extensive and useful body of information on this science, which has yet been published in Britain. Other performances likewise, particularly those of Mr. Emerson and Dr. Keill, have much merit. But, with the exception of the System of Professor Vince, none of these suit the present matured state of the science: books of astronomy must, from the nature of the subject on which they treat, have a very contracted period of utility, in comparison with that which is allotted to works on pure and abstract science: the latter may be advanced to a very high degree of perfection by the exertions of an individual, and may

:

* The Authour speaks here of Astronomical works published in England; for the excellent ones published in France, and not translated, are by no means fo generally known in this country as might be wished; indeed, most of them are so expensive, that there is but little prospect of their obtaining a place in the library of every mathematician.