56 
THE AMAZON AND MADEIRA RIVERS. 
]3ut neither there, nor higher tip in Bolivia, conhl we discover any trace 
of these “fonndlings,” even as Agassiz liimself was nnahle to discover, in 
the environs of Eio de Janeiro, the striees'’ and ^’‘7'oches moutonnees^^ 
of Switzerland, which testify to an ice-period with its immense glaciers. 
Agassiz attributes their absence to the rapid crumbling of the rocks 
under the comhiued influence of the tropical sun and rain ; but he seems 
to overlook the fact that they diminish much faster iu moderate climates, 
by the severe disintegrating operation of freezing water penetrating into 
the smallest crevices.* 
While employed as engineer on a roadf in the province of Minas 
Geraes, I had occasiou to examine numerous specimens of the spheroidic 
boulders of diorite, Avith their concentric coatings of red clay, pronounced 
to he “foundlings” by Agassiz. To me these shell-shaped crusts 
appeared to bo rather the effect of the cooling process, the more so as the 
ferruginous clay ahvays AA'as of a more intense hue, like that of burnt 
ochre, nearest the diorite ball. 
Seen from the foot of the projecting hill crowned Avith the remains of 
the Destacamento, the many breaks of the Theotonio Cataeact, indeed, 
offer a grand spectacle. It extends acro.ss the Avholc riA^er (7C0 yards), 
and has, in general, an angle of 45°. In the middle of it emerges a 
rooky cone, whose dark colour contrasts sharply Avith the dazzling Avliite 
foam and spray. Close to the right bank, Ailiere the bulk of the Avater is 
discharged, the AvaAms rise to a height of 33 feet, and we there saAV the 
gigantic trunk of a drifting forest-tree tossed and Avhirlcd about as if it 
Avere a light reed. 
From Santo Antonio to above Theotonio there is no great interval 
between the banks, there being an almost uninterrupted succession of 
hills from 20 to 40 foot high, densely Avooded, as the country generally 
is, though the vegetation is not so rich and luxuriant as we had found it 
below Santo Antouio. 
The next rapid is Moiuimnos (little hill), where we had to empty the 
* In Eio do Janeiro and otlior Brazilian towns thoro aro a groat many cupolas of 
oliurolies, ten-aces, vases, and nrchitcctiu-al ornaments of eveiy land, covered only with 
common mortar, which have successfully resisted tho sun and rain of a centiu-y or more ; 
whereas, iu our own “moderate” climate, they would not last throe years. 
f This was constructed hy the Company Uniao e ludustria (President, Marianno 
Procopio Ferreira Lage; Engineers, Joseph Keller and Bulthos) ; the first and most 
tixtousivo road in Brazil (it is 90 miles long). The difficulties of surmounting tho water- 
sheds were considerable. The iron girder bridge, 502 feet long, over the Parahyba, near 
Tres-Barras, after the plans of Josepli Keller, is a remarliable piece of work. 
