18 AUTOBIOGRAPHY OF FRANCIS ARAGO. 
yond the seas, and thus relieved me from the most serious 
anxiety which I have experienced in all my life. 
Brissot died after having covered the walls of Paris 
with printed handbills in favour of the Bourbon restora- 
tion. 
I had scarcely entered the Observatory, when I be- 
came the fellow-labourer of Biot in researches on the 
refraction of gases, already commenced by Borda. 
While engaged in this work the celebrated academi- 
cian and I often conversed on the interest there would be 
in resuming in Spain the measurement interrupted by the 
death of Méchain. We submitted our project to Laplace, 
who received it with ardour, procured the necessary 
funds, and the Government confided to us two this im- 
portant mission. 
M. Biot, I, and the Spanish commissary Rodriguez 
departed from Paris in the commencement of 1806. 
We visited, on our way, the stations indicated by Mé- 
chain; we made some important modifications in the pro- 
jected triangulation, and at once commenced operations. 
An inaccurate direction given to the reflectors estab- . 
lished at Iviza, on the mountain Campvey, rendered the 
observations made on the continent extremely difficult. 
The light of the signal of Campvey was very rarely 
seen, and I was, during six months, in the Desierto de 
las Palmas, without being able to see it, whilst at a later 
period the light established at the Desierto, but well di- 
rected, was seen every evening from Campvey. It will 
easily be imagined what must be the ennui experienced 
by a young and active astronomer, confined to an elevated 
peak, having for his walk only a space of twenty square 
metres, and for diversion only the conversation of two 
Carthusians, whose convent was situated at the foot of 
