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thermometer did not raise sensibly above 20 or 22 de- 
grees of Reaumur in the month of July or August; the 
degree of heat of an ordinary summer in Europe. Du- 
ring my residence the sea-breezes reigned continually, 
the air was nearly always full of moisture, and the hy- 
grometer marked a very high degree of moisture or the 
days when the greatest heat ought to have been felt. 
I look upon the ophthalmia as the only epidemic dis- 
order of the country, and as proceeding from a purely 
mechanical cause, namely, the imperceptible grains of 
sand that the wind carries with it, and which entering 
the eye, produce a sort of itching, which causes it to be 
rubbed; and as the organ is much irritated by this pro- 
cess, as well as by the great reflection of the sun, the 
least grain of this saline sand entering into it, hurts the 
outer coat, and produces an inflammation. There are 
very few persons who escape this complaint; and being 
persuaded of the truth of this, whenever I felt any ex- 
traneous particle in my eye, I resisted the inclination I 
had to rub it, and this precaution preserved me from 
ever having the disorder. 
I did not use so much foresight in regard to the 
changes in the temperature of the climate in autumn, 
which take place so suddenly, that in the short space of 
three or four hours, 1 myself felt several variations from 
heat to cold. The usual method to prepare against 
these changes, is to make use of warm clothing; how- 
ever, notwithstanding my precautions, I was indisposed 
twice. 
I have looked upon the history of the countries I 
have visited, as an object foreign to the account of my 
travels; however, the singular political situation of 
