SOUTHERN AFRICA. 15 
of Linnaeus) commands attention to its clear melodious note. 
It sings delightfully in the cage, but is reared with great diffi- 
culty, and lives entirely on sugar and water. 
The mountains that form the eastern boundary of the valley 
are eminently grand, their upper regions being masses of 
bare rock destitute of a single shrub, or even a blade of grass. 
They are a part of that great chain that stretches from False 
Bay to the northward, and to which a French naturalist ha-s 
given the name of the Back-bone of the Earth ; a name, how- 
ever, that is much more appropriate on account of their 
singular appearance than great extent. Their naked summits 
are pointed and jagged, and divided like the vertebrae of the 
back-bone of an animal. They consist of a number of sand- 
stone strata, placed in a horizontal direction, contain a great 
deal of iron, being in places perfectly red, and they rest upon 
beds of granite, clay, and slate. This range of mountains, 
like an immense wall, shuts out entirely from the Cape the 
countries that lie beyond it ; so complete a bulwark, indeed, 
is this chain of mountains, that a few men in possession of the 
passes would always be able to cut off all communication 
between the sea-coast and the interior. Of these passes, or 
, kloofs as they are called by the colonists, there are but three 
that are ever crossed with wheel carriages : Hottentot Hol- 
land's Kloof near False Bay, which opens a communication 
with the district of Swellendam and the eastern parts of the 
colony along the sea-coast : Roode Sand, or red sand, Kloof, 
opposite to Saldanha Bay, leading to Graaf Reynet, and the 
remotest parts of the colony ; and Eland s Kloof, still farther 
