Mineralogy and feneay- 123 
very different from our own ; and that such, on the contrary, as we meet 
with in the most recent beds, become more analogous to the species 
which still grow in these same countries, as the geological eae to 
which they belong approaches nearer oa age 
Every thing, therefore, proves, ont e hand, that the different 
vegetable creations which have Heat — other on the globe have 
become more and more perfect ; on the other hand, that the climate of 
4. Geo logy and Topography. of the Isthmus of Panama; by Eva 
Hopaixs, C.E., F.G.S., (Mining Journal, April 8, 1848; tbelaied 
from the Bogoté Gazette of the Oth Sept. 1847. )—By reference to a 
prepared plan, it will ‘be observed that the Cordillera of mountains, form- 
ing the chain of union between the two i agereaik is curved in the shape 
of an are on the Isthmus of Panama—the c x side faces the north, 
the easterly portion runs in a south-eastern pipes towards Darien, 
is broken, and the co ntinuity of the chain interrupted by the oblialle 
intersection of the River C! agres. ‘Towards the north-east, between 
th f we 
Boqueron Principally on L bed of e river, owing to the re ani 
ag feet nature of the banks, ae numerous and deep waterfalls ied 
s, which exist near its source, render it necessary to leav 
the ese and travel along the steep sides of the surrounding mour roke 
The heads of this river consist of various branches, one 0 which arises 
nt it y tee from the oe ay union of the Pequent to half its extent. 
The river and the road being synonymous terms in this route, our road 
continued descending as before, but rather in the waters of the Cascajal . 
along its” 
Portobelo. The great difficulties and obstructions, caused 
ions, this route, and the choice made of sucha 
direc are a strong g proof that the Spaniards found insuperable ‘ob- 
saeriod to the formation of a pa road between Portobe 
From the € pass in the mountain above alluded to, ase Ri Se 1e 
chain is divided into numerous longitudinal branches ; one pew 
Portobelo, and terminates abruptly in the sg af this port Paka a 
elevation of 600 feet ; TI 9 ag Me ds 
