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sardous livelihood did not last long. The frost of 1779 will be long remembered in the Floridas; and young Bowles, almost naked, superior to the injuries of men, found in the elements an enemy which neither strength of constitution nor fortitude of mind could withstand. He wanted shelter, and it was not long before he received it. Among the inhabitants of the town, who saw his situation, there was one, a baker by profession, who had a heart to commiserate and to relieve him. Under the roof of this hospitable stranger he remained the greatest part of the winter, who finding him a strong and robust lad, thought it but reasonable that he should assist to make the bread which he so plentifully ate.

Highly impressed, as no doubt be was, with a sense of obligation for such unmerited goodness, an aversion to labour, peculiar to the habits in which he had so lately indulged, made him reject the proposal, and he would again have been exposed to all his former dangers but for s old the Creeks.

friends extraordinary inclemency of the seasc.. had brought them down for presents, and Bowles once more returned with them, and remained near two years. The friendly character of North American savages, when not irritated by resentment, or made sanguinary through thirst of revenge, is well known. During this period, such was their mutual regard, that he strengthened the ties of friendship by marrying a daughter of one of their chiefs. Thus he became doubly united to them, both from inclination and the ties of blood; and his children were living pledges of their father's fidelity.

"Habit had now confirmed his predilection for a state of nature; and, on the commencement of hostilities between Great Britain and Spain, he was thought worthy of being enrolled among the fighting, men of this warlike nation. Nor did he discredit their choice. His conduct throughout the war was eminently distinguished for coolness and vigour in action; and the most eminent chiefs pointed him out as an example worthy of imitation."

Mr. Bowles, increasing in the favour and esteem of the Indians, was raised to be their leader. On account of his attachment to the interests of

Great Britain, he has suffered much from the court of Spain; but nothing appears sufficient, from the accounts before us, to alter the steady purpose of his pursuits. The interests of the Indians appear to engage his atten tion and his assiduity, and no doubt he will do much towards their civili zation and happiness.

This work contains not only the history of the characters, but their political connections, and extracts from their speeches in the Houses of Parliament.

VI. LETTERS of EULER on different Subjects in Physics and Philofophy, addressed to a German Princess. Translated from the French, by HENRY HUNTER, D. D. with original Notes, and a Glossary of Foreign and Scientific Terms. With nineteen Plates. Second Edition, in Two Volumes 8vo. Boards. Murray and Highley, Cuthell, Vernor and Hood.

HE design of this interesting

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Twork thus expressed by the translator, in his preface: "Euler wrote these letters for the instruction of a young and sensible female, and in the same view that they were written they are translated, namely, for the improvement of the female mind; an object of what importance to the world! I am old enough to remember the time when well-born young women, even of the north, could spell their own language but very indifferently, and some hardly read it with common decency; when the young lady's hand-writing presented a medley of outlandish characters; and when a column of pounds shillings and pence presented a labyrinth as inextricable as the extraction of the cube root. While the boys of the family were conversing with Virgil, perhaps with old Homer himself, the poor girls were condemned to crossstitch on a piece of gauze canvas, and to record their own age at the bottom of a sampler.

"They are now treated as rational beings, and society is already the better for it. And wherefore should the terms female and philofophy seem a

ridiculous combination? Wherefore preclude to a woman any source of knowledge to which her capacity and condition in life entitle her to apply?

It is cruel and ungenerous to expose the frivolity of the sex, after reducing it to the necessity of being silly and frivolous. Cultivate a young woman's understanding, and her person will become, even to herself, only a secondary concern; let her time be filled up in the acquisition of attainable and useful knowledge, and then she will cease to be a burden to herself and to every lady about her; make her acquainted with the world of nature, and the world of art will delude her no longer.

"The time, I trust, is at hand, when the Letters of Euler, or some such book, will be daily on the breakfasting table, in the parlour of every female academy in the kingdom; and when a young woman, while learning the useful arts of pastry and plain-work, may likewise be acquainting herself with the phases of the moon, and the flux and reflux of the. tides. And I am persuaded she may thrum on the guitar, or touch the keys of the harpsichord, much more agreeably both to herself and others, by studying a little the theory of sound. I have put the means of this in her power; it will be at once her fault and her folly if she neglect it." Translator's Preface, p. 18, 19, 20, 21.

For the character of this work we present our readers with an extract from the advertisement to the French edition.

"The Letters of Euler to a German Princess have acquired, over all Europe, a celebrity, to which the reputation of the Author, the choice and importance of the several subjects, and the clearness of elucidation, justly entitle them. They have deservedly been considered as a treasury of science, adapted to the purpose of every common seminary of learning. They may be studied to advantage without much previous elementary knowledge; they convey accurate ideas respecting a variety of objects, highly interesting in themselves, or calculated to excite a laudable curiosity; they inspire a proper taste for the sciences, and for that sound philosophy which, supported by science, and never losing sight of her cautious, steady, methodical advances, runs no risk of perplexing or misleading the attentive student." P. 27.

The eulogium of Euler, containing some interesting traits of his character

and events of his life, is prefixed to the letters, from which we give the following outline.

"Leonard Euler, President of the Mathematical School in the Academy of Petersburg, and previously in that of Berlin, Fellow of the Royal Society in London, and of the Academies of Turin, Lisbon, and Bâle, Foreign Associate of that of the Sciences, was born at Bâle, April the 15th, 1707, being the son of Paul Euler and Margaret Brucker.

"His father, who, in 1708, undertook the pastoral charge in the village of Riechen, in the vicinity of Bale, was his first instructor; and he enjoyed betimes the pleasure of contemplating the progress of his son's expanding faculties and dawning glory, a cordial so reviving to the heart of a parent, advance under his own eye, and gather strength from his own assiduities." P. 33.

"He prosecuted his studies at the university of Bâle, and such was his early proficiency, that he was deemed not unworthy the attention, and particular instructions of John Bernouilli, who was his father's mathematical instructor.

"When he had scarcely attained the degree of Master of Arts, his father, who intended him for his own successor, enjoined him to exchange the study of the mathematics for that of theology. Happily the effect of this act of authority was of short duration. It proved no difficult matter to per suade the father, that his son was destined to supply to the learned world the place of John Bernouilli, and not sink into the obscure parson of Riechen.

"An essay, composed by Euler in his nineteenth year, on the masting of ships, a subject proposed by the Academy of Sciences, procured him, in 1727, an addition to his academical honours, so much the more respectable, that the youthful native of the Alps could have derived no assistance from practical knowledge, and that he yielded the palm to M. Bouguer alone, an able geometrician, then at the zenith of his reputation, and for ten years before Professor of Hydrography in a maritime city." P.35.

Daniel and Nicholas Bernouilli, sons and pupils of John Bernouilli, whose friendship he secured while at the university by his application and good dispositions, had been invited

to Russia. Euler felt the sincerest regret at parting with the friends of his youth, and engaged them to promise their utmost exertions to procure him a similar invitation, to which request the brothers conscientiously attended. "Euler having stood an unsuccessful candidate for a vacant chair in the university of Bale, soon after set out for Russia under auspices the most melancholy and discouraging. It was not long before he received intelligence that Nicholas Bernouilli had fallen a victim to the severity of the climate; and the very day he set foot on Russian ground, Catharine I. paid the debt of nature. This event, at first, seemed to threaten the approaching dissolution of the Academy, whose establishment that princess had just completed, in compliance with the will of the deceased czar, her husband.

"Euler, at a prodigious distance from his native country, destitute of the advantage which Daniel Bernouilli possessed, that of an illustrious and respected name, to prepare his way, formed the resolution of enter ing into the Russian marine service. One of the admirals of Peter 1. had already promised to procure him a situation, when, happily for geometry, the storm which had lowered over the sciences spent itself. Daniel BerBouilli retired into his own country: Euler was declared Professor of Geometry, and successor to his illustrious friend, in 1733." P. 37.

At the earnest solicitation of the king of Prussia, he went from Petersburg to Berlin in 1741, and continued at the latter place till 1766.

"The princess D'Anhalt Dessau, niece to Frederic II. king of Prussia, was desirous of receiving from him some lessons in natural philosophy. These lessons have been published, under the title of Letters to a German Princess, a work inestimable for the singularly clear light in which he has displayed the most important truths of mechanics, of physical astronomy, of optics, and of the theory of sound, and for the ingenious views, less philosophical, but more sage, than those which have made Fontenelle's Plurality of Worlds outlive the System of Vortices." P. 52.

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The government of Russia had never treated Euler as a stranger. Notwithstanding his absence, part of his salary was always regularly paid;

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and in 1766, the empress having given him an invitation to return to Petersburg, he complied." P. 55.

"As long as his sight remained, (for it appears, that by close application to study he had lost that faculty) he every evening collected to domestic devotion, his grand-children, his domestics, and such of his pupils as lodged in the house; he read to them a portion of scripture, and sometimes accompanied it with an exposition." P. 60.

"Of sixteen professors belonging to the Academy of Petersburg, eight had been formed by him; and all of them, well known from their productions, and decorated with academic honours, value themselves on being able to add, to all the rest, that of disciple to Euler.

"He had retained all his facility of thought, and, apparently, all his mental vigour: no decay seemed to threaten the sciences with the sudden loss of their great ornament. On the 7th of September, 1783, after amusing himself with calculating on a slate the laws of the ascending motion of air-balloons, the recent discovery of which was then making a noise all over Europe, he dined with Mr. Jexel and his family, talked of Herschell's planet, and of the calculations which determined its orbit. A little after he called his grand-child, and fell a playing with him as he drank tea, when suddenly the pipe, which he held in his hand, dropped from it, and he ceased to calculate and to breathe.

"Such was the end of one of the greatest and most extraordinary men ever produced by the hand of nature, a man whose genius was equally capable of the greatest efforts, and of the most unwearied application, who multiplied his productions far beyond what could have been expected from powers merely human, and was, nevertheless, original in every one; whose head was incessantly employed, and his spirit always tranquil; who, finally, by a destiny unfortunately too rare, united, and that deservedly, a felicity hardly ever interrupted, to a glory which no one ever disputed with him."

"His death was considered as a public loss, even in the country which he inhabited. The Academy of Petersburg went into deep mourning for him, and voted a marble bust of him,

at their own expence, to be placed in their assembly-hall. An honour still more distinguished had already been conferred upon him by that learned body, in his lifetime. In an allegorical painting, a figure of Geometry is represented leaning on a tablet, exhibiting mathematical calculations, and the characters inscribed, by order of the academy, are the formulas of his new theory of the moon. Thus, a country which, at the beginning of the present century, we con sidered as scarcely emerged out of barbarisin, is become the instructor of the most enlightened nations of Europe, in doing honour to the life of great men, and in embalming their memory; it is setting these nations an example, which some of them may blush to reflect that they have had the virtue neither to propose nor to imitate." P. 65, 66, 67.

The contents of the first volume are comprised in 115 letters upon the following subjects:

Letter 1. Of magnitude, or extension.-2. Of velocity.-3. Of sound and its velocity.-4. Of consonance and dissonance.-5. Of unison and octaves.-6. Of other consonances. 7. Of the twelve tones of the harpsichord.-8. Of the pleasure derived from fine music.-9. Compression of the air.-10. Rarefaction and elasticity of the air.-11. Gravity of the air.-12. Of the atmosphere, and the barometer.-13. Of wind-guns, and the compression of air in gunpowder.-14. The effect produced by the heat and cold on all bodies, and of the pyrometer and thermome. ter.-15. Changes produced in the atmosphere by heat and cold.-16. The cold felt on high mountains and great depths accounted for.-17. Of light, and the systems of Descartes and Newton.-18. Difficulties attend. ing the system of emanation.-19. A different system respecting the nature of rays and of light proposed. 20. Of the propagation of light.-21. Digression on the distances of the heavenly bodies, and on the nature of the sun and his rays.-22. Elucidations on the nature of luminous bodies, and their difference from opaque bodies illumined.-23. How opaque bodies become visible. Newton's system of the reflection of rays, proposed.-24. Examination and refutation of Netoton's system.-25, 26. A different explanation of the manner in which opaque bodies illumi

nated become visible.-27. Clearness and colour of opaque bodies illumined.-28. Nature of colours in particular.-29. Transparency of bodies relative to the transmission of rays. 30. Of the transmission of rays of light.-31. Rarefaction of rays of different colours.-32. Of the azurecolour of the heavens.-33. Of rays issuing from a distant luminous point, and of the visual angle.-34. Of the supplement which judgment lends to vision.-35. Explanation of certain phenomena relative to optics.36. Of shade.-37. Of catoptrics, and the reflection of rays from plain mirrors.-38. Reflection of rays from convex and concave mirrors. Burning mirrors-39. Of dioptrics.-40. Continuation of burning-glasses, and their focus.-41.Ofvision, and the structure of the eye.-42. Wonders discoverable in the structure of the eye.-43. Astonishing difference between the eye of an animal and the artificial eye, or camera obscura.-44. Perfections discoverable in the structure of the eye.-45. Of gravity, considered as a general property of body.-46. Of specific gravity.-47. Terms relative to gravity, and their true import.-48. Reply to certain objections to the earth's spherical figure derived from gravity.49. True direction and action of gravity relatively to the earth.-50. Different action of gravity with respect to certain countries and distances from the centre. The earth.-51. Gravity of the moon -52. Discovery of universal gravitation by Newton.-53. Of the mutual attraction of the heavenly bodies.-54. Different sentiments of philosophers respecting universal gravitation. The attrac tionists.-55, 56, 57. Power by which the heavenly bodies are mutually attracted.-58. Motion of the heavenly bodies. Method of determining it by the laws of gravitation.-59, 60. System of the universe.-61. Small irregularities in the motions of the planets caused by their mutual_attraction.-69. Description of the flux and reflux of the sea.-63. Different opinions of philosophers respecting the flux and reflux of the sea.-64, 65, 66, 67. Explanation of the flux and reflux, from the attractive power of the moon.-68. More particular account of the dispute respecting universal gravitation-69. Nature and essence of bodies, or extension, mobility, and impenetrability of body.— 70. Impenetrability of bodies.—71.

⚫ of the motion of bodies, real and apparent.-72. Of uniform, accelerated, and retarded motion.-73. Principal law of motion and rest, disputes of philosophers on the subject.-74. Of the inertia of bodies: of powers. 75. Changes which may take place in the state of bodies.-76. System of the monads of Wolff.-77. Origin and nature of powers.-78. Principle of the least possible action.-79. On the question, Are there any other species of powers?-80. Of the nature of spirits.-81. Of the union between the soul and the body.-82. Different systems relative to the subject. 83, 84. Examination of the system of free established harmony. Two objections to it.-85, 86. Of the liberty of spirits, and a reply. to objections against liberty.-87. Influence of the liberty of spirits upon events.-88. Of events natural, supernatural, and moral.-89. Of the question respecting the best world possible, and of the origin of evil.― 90. Connection of the preceding considerations with religion. Reply to the objections of the philosophic systems against prayer.-91. The liberty of intelligent beings in harmony with the doctrines of the Christian religion.-92. Elucidation respecting the nature of spirits.-93. Reflection on the state of souls after death.-94. Considerations on the action of the soul upon the body, and of the body upon the soul.-95. Of the faculties of the soul, and of judgment.-96. Conviction of the existence of what we perceive by the senses. Of the idealists, egotists, and materialists.97. Refutation of the idealists.-98. The faculty of perceiving, reminiscence, memory, and attention. Simple and compound ideas.-99. Division of ideas into clear and obscure, distinct and confused. Of distraction.-100. Of the abstraction of notions. Notions general and individual. Of genus and species.-101. Of language; its nature, advantages, and necessity, in order to the communication of thought, and the culti vation of knowledge.-102. Of the perfection of a language: Judgment and nature of propositions, affirmative and negative, universal or particular.-103. Of syllogisms, and their different forms when the first proposition is universal.-104. Different forms of syllogisms, whose first proposition is particular.-105. Analysis VOL. 1.

of some syllogisms.-106. Different figures and modes of syllogisms.-107. Observations and reflections on the modes of syllogisms.-108. Hypothetical propositions, and syllogisms constructed of them.-109. Of the impression of sensations on the soul.

110. Of the origin and permission of evil; and of sin.-111. Of moral and physical evil.-112. Reply to complaints of the existence of physical evil.-113. The real destination of man's usefulness, and necessity of adversity.-114. Of true happiness, Conversion of sinners. Reply to objections on the subject.-115. The true foundation of human knowledge. Sources of truth, and classes of information derived from it.

Mr. Euler combats the system of Newton, on the reflection of rays of light: as his arguments occupy more room than we can devote to the subject, the following letter, in which the author defends his own system, is selected:

LETTER XXXVIII.

"Nature of Colours in particular. "The ignorance which prevailed respecting the true nature of colours, has occasioned frequent and violent disputes among philosophers, each of whom made an attempt to shine, by maintaining a peculiar opinion on the subject. The system which made colours to reside in the bodies themselves, appeared to them too vulgar and too little worthy of a philosopher, who ought always to soar above the multitude. Because the clown imagines that one body is red, another blue, and another green, the philoso pher could not distinguish himself better than by maintaining the contrary; and he accordingly affirms, that there is nothing real in colours, and that there is nothing in bodies relative to them.

The Newtonians make colours to consist in rays only, which they distinguish into red, yellow, green, blue, and violet; and they tell us that a body appears of such and such a colour, when it reflects rays of that species. Others, to whom this opinion seemed absurd, pretend that colours exist only in ourselves. This is an admirable way to conceal ignorance; the vulgar might otherwise believe that the scholar was not better acquainted with the nature of colours than themselves. But you will readily

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