REPORT ON GEOLOGY, 
387 
in his journeys across these mountains in 1816 and 1820, was 
the first to throw a more accurate light on this subject (see his 
Notice on the structure of the Alps, and tabular arrangement 
of the rocks that occur in them, with their equivalents in En¬ 
gland, published in the Annals of Philosophy , June 1821); 
about the same period Brongniart published his discovery of 
green-sand on the Diablerets ; but it is to the recent investiga¬ 
tions of Mr. Murchison and of Prof. Sedgwick (who became the 
companion of the former in all his later tours), that we owe the 
satisfactory completion of this great work; and it is with their 
names that the accurate comparative estimation of the mem¬ 
bers of the secondary series as exhibited in this the grandest 
of our mountain chains, must remain associated. Boue has 
indeed ably cooperated in the same work; nor can the trifling 
difference of opinion on the age of the Gosau rocks, (whether 
belonging to the beds immediately below or immediately above 
the cretaceous group,) materially interfere with the many and 
important points of their agreement. Lilienbach on the Alps 
of Saltzbourg, Studer on the Southern Alps, and with refer¬ 
ence to other portions of the chain, Hagi’s observations on the 
Bernese Oberland, and Lusser’s section of St. Gothard, may 
also be advantageously compared with the writers before named. 
Risso has fully described the Italian portion of the Maritime 
Alps, and De la Beche and Buckland have also published on 
the environs of Nice. 
But while we justly refer to these later authorities for the 
complete development of the formations constituting this great 
chain, it must not be forgotten, that as early as 1759 Ardu- 
ino, in his description of the Alpine slopes bordering the Vicen- 
tin Veronese and Padua, had fully anticipated much that has 
been confirmed by more recent observation: his general sketch of 
the Alpine chains, as subdivided into their primitive, secondary, 
and tertiary ranges, could scarcely be improved in the present 
day, and is much more complete than the contemporaneous 
division of Lehman into primitive and secondary only; he has 
enumerated generally the characteristic fossils peculiar to the 
several beds, and seems quite aware of their constant relation 
ceous slate containing garnets, yet presenting encrinites and other transition 
fossils; the Alpine limestones, considered as equivalent to our oolites, are also 
distinguished by their containing masses of galena, and the middle portion of 
the series contains the principal deposits of rock salt. Is it too rash a speculation 
to attribute these modifications to the more continued and intense agency of 
the volcanic forces which we may suppose to have elevated these colossal ridges ? 
M. de Beaumont even considers the crystalline slates of St. Gothard as altered 
secondary rocks. 
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