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Adriatic Sea were very confiderable, very fatiguing, 
and very dangerous. His paffion for natural hiftory, 
his particular inclination to botany, and the pleafure 
of purfuing his refearches into countries before un- 
known to obfervers, made him refolutely furmount 
thofe difficulties. 
His inquiries have enabled him to determine upon 
his own knowledge, that there is very little difference 
between the bottom of the Adriatic Sea and the fur- 
face of the nelgbouring countries. There are at the 
bottom of the water, mountains, plains, vallies, and 
caverns, juft as upon the land. The foil confifts of 
diffent ftrata placed one upon another j and, for the 
moft part, parallel and correfpondent to thofe of the 
rocks, iflands, and neighbouring continents. They 
contain ftones of different forts, minerals, metals, va- 
rious petrified bodies, pummice-ftone, lava’s, formed 
by Volcanos, 
Iftria, Morlachia, Dalmatia, Albania, and fome 
other adjacent countries, as well as the rocks, the 
iflands, and the correfpondent bottom of the Adriatic 
Sea, confift of a mafs of a whitifh marble, of an uni- 
form grain, and of almoft an equal hardnefs. It is 
that kind of marble called by the Italians marmo di 
Rovigno , and known to the antients by the name of 
marmor Tragurienfe, 
This vaft bed of marble, in many places under ' 
both the earth and the fca, is interrupted by leve- 
ral other kinds of marble, and covered by a great 
variety of bodies. There are difeovered there, 
for inftancc, gravel, fand, and earths mare or lefs 
fat. 
The 
