190 AUTOBIOGRAPHY OF FRANCIS ARAGO. 



I would not be guilty of any rudeness toward the Academy, If they 

 were to receive the declaration for which I am asked, would not the 

 savans who composed this illustrious body have a right to say to rac : 

 "How are you certain that we have thought of you? You refuse what 

 has not yet been offered to you.'" 



On seeing my lirm resolution not to lend myself to the inconsiderate 

 course which he had advised me to follow, M. de Laplace went to work 

 in another waj' : he maintained that I had not suflicient distinction for 

 admission into the Academy. I do not i^retend that, at the age of 

 thrce-aud-twenty, my scientific attainments were very considerable, if 

 estimated in an absolute manner; but when I judged b}- comparison, I 

 regained courage, especially on considering that the three last years of 

 my life had been consecrated to the measurement of an arc of the meri- 

 diaii in a foreign country ; that they were passed amid the storms of the 

 ■war with Spain; often enough in dungeons, or, what was yet worse, in 

 the mountains of Kabylia, and atxVlgiers, at that time a very dangerous 

 residence. 



Uere is, therefore, my statement of accounts for that epoch. I make 

 it over to the impartial appreciation of the reader: 



On leaving the Polytechnic School, I had made, in conjunction with 

 M. liiot, an extensive and very minute resean-h on the determination of 

 the coellicicnt of the tables of atmosi)heric reiVaction. 



We had also measured the refraction of dillerent gases, which, up to 

 that time, had not been attempted. 



A determination, more exact than had been previously obtained, of 

 the relation of the weight of air to the weight of mercury, had furnished 

 a direct value of the coefticient of the barometrical formula which served 

 for the calculation of the heights. 



1 had contributed, in a regular and very assiduous manner, during 

 nearly two years, to the observations which were m;ule day and night 

 with the transit telescope and with the mural quadrant at the Paris 

 Observatory. 



I had undertaken, in conjunction with ISI. Bouvard, the observations 

 relating to the verification of the laws of the moon'.s libration. All the 

 calculations were i')repared ; it only remained for me to put the numbers 

 into the ibrmuhx;, when I was, by order of the P>ureau of Longitude, 

 o!)liged to leave Paris for Spain. I had observed various comets, and 

 calculated their orbits. I had, in concert with .AI. Louvard, calculated, 

 according to Lai)lace's formula, tlic table of reiVaction which has been 

 ])ublished in the Rccucil dcs Tables of the Bureau of Longitude, and in 

 the ConiKiLssdiice dcs Temps. A research on the velocity of light, made 

 "With a i)rism placed befcre the object end of the telescope of the nuu'al 

 circle, had proved that the same tables of refraction might serve for the 

 sun and all tlie stars. 



Finally, 1 had just terminated, under very difficult circumstances, the 



