Part 3

Optical Labours 301

LAPLACE.

Preliminary Notice 303

APPENDIX.

(A.) Brief Notice of some other interesting Results of the Researches of Laplace which have not been mentioned in the Text 368

(B.) The Mecanique Celeste 372

JOSEPH FOURIER.

Preliminary Notice 374

Birth of Fourier.--His Youth 377

Memoir on the Resolution of Numerical Equations 380

Part played by Fourier in our Revolution.--His Entrance into the Corps of Professors of the Normal School and the Polytechnic School.--Expedition to Egypt 384

Fourier Prefect of L'Isere 405

Mathematical Theory of Heat 408

Central Heat of the Terrestrial Globe 419

Return of Napoleon from Elba.--Fourier Prefect of the Rhone.--His Nomination to the Office of Director of the Board of Statistics of the Seine 430

Entrance of Fourier into the Academy of Sciences.--His Election to the Office of Perpetual Secretary.--His Admission to the French Academy 437

Character of Fourier.--His Death 438

LIVES

DISTINGUISHED SCIENTIFIC MEN.

THE HISTORY OF MY YOUTH:

AN AUTOBIOGRAPHY OF FRANCIS ARAGO.

I have not the foolish vanity to imagine that any one, even a short time hence, will have the curiosity to find out how my first education was given, and how my mind was developed; but some biographers, writing off hand and without authority, having given details on this subject utterly incorrect, and of a nature to imply negligence on the part of my parents, I consider myself bound to put them right.

I was born on the 26th of February, 1786, in the commune of Estagel, an ancient province of Roussillon (department of the Eastern Pyrenees). My father, a licentiate in law, had some little property in arable land, in vineyards, and in plantations of olive-trees, the income from which supported his numerous family.

I was thus three years old in 1789, four years old in 1790, five years in 1791, six years in 1792, and seven years old in 1793, &c.

The reader has now himself the means of judging whether, as has been said, and even stated in print, I had a hand in the excesses of our first revolution.

My parents sent me to the primary school in Estagel, where I learnt the rudiments of reading and writing. I received, besides, in my father's house, some private lessons in vocal music. I was not otherwise either more or less advanced than other children of my age. I enter into these details merely to show how much mistaken are those who have printed that at the age of fourteen or fifteen years I had not yet learnt to read.

Estagel was a halting-place for a portion of the troops who, coming from the interior, either went on to Perpignan, or repaired direct to the army of the Pyrenees. My parents' house was therefore constantly full of officers and soldiers. This, joined to the lively excitement which the Spanish invasion had produced within me, inspired me with such decided military tastes, that my family was obliged to have me narrowly watched to prevent my joining by stealth the soldiers who left Estagel. It often happened that they caught me at a league's distance from the village, already on my way with the troops.

On one occasion these warlike tastes had nearly cost me dear. It was the night of the battle of Peires-Tortes. The Spanish troops in their retreat had partly mistaken their road. I was in the square of the village before daybreak; I saw a brigadier and five troopers come up, who, at the sight of the tree of liberty, called out, "Somos perdidos!" I ran immediately to the house to arm myself with a lance which had been left there by a soldier of the levee en masse, and placing myself in ambush at the corner of a street, I struck with a blow of this weapon the brigadier placed at the head of the party. The wound was not dangerous; a cut of the sabre, however, was descending to punish my hardihood, when some countrymen came to my aid, and, armed with forks, overturned the five cavaliers from their saddles, and made them prisoners. I was then seven years old.