114 Account of the Caroline Islands. 
ness is about equal to that of fluor. Fragments, taken indiscrimi- 
nately from all portions of the rock, afford also a water cement, but 
one probably, of inferior quality. However, the discovery, simple 
as it is, is of too recent a nature to allow of my saying much beyond 
the mere fact. 
Art. XI.— Account of the Caroline Islands by the Russian expe- 
dition for exploring the Russian Coasts of Asia and America. 
From the Bibliothéque Universelle, Juillet, 1934. 
Ir will be remembered that in 1826, the Russian Government 
fitted out two corvettes, the Moller and the Seniavine, to explore 
these regions so little known, and so dangerous to navigators, on ac- 
count of: the numerous islands they contain, as well as for the pur- 
pose of describing the natural history of that interesting part of the 
world. The expedition was entrusted to the command of Capt. 
Lurxe; and C. H. Mertens was the chief naturalist. Two drafts- 
men of distinguished merit, M. M. Kirtirz, and Postrets, were 
' attached to the expedition. It has brought home fine collections in 
zoology and botany, which it is expected will soon be figured and pub- 
lished under the direction of the academy of St. Petersburgh. | 
‘Before giving some account of the only memoir relative to these 
voyages, we shall briefly notice the history of its author, Mertens, 
who, unfortunately for science, died soon after his return to St. Pe- 
tersburgh. He was born at Bremen, May 17, 1796. His father 
was director of the school of commerce at Bremen, and was one of 
the first botanists of Germany. He had devoted biineett particular- 
ly, and with the most remarkable success to the study of the Alge, 
and although he had never published upon the subject, yet he was 
the principal regulator of this complex department. At the mo- 
ment when he was about to publish his algology, the fruit of forty 
years labor, an accident deprived him of his manuscript. He died 
in 1831, about one year after his son, who gave promise by his abili- 
ties of sustaining the reputation of the family. The son commenced 
his career when quite young, by enlisting asa soldier, in the war, in 
which Germany defended its nationality against France; and he 
afterwards travelled through various countries, finally fixing hingelt’ in 
Russia, and renewing ihe pursuit of natural history, to which his 
