THE CAMEL. 
129 
^hina are distributed by means of caravans 
^^il’ough central Asia ; while, by means of the 
'^^•inel, articles sold in the market of Tim- 
“'ictoo are bartered for the commodities of 
^atnarcand and Tibet. There are caravans 
^^ading between Cairo and the interior of 
■Africa, and penetrating far beyond the limits 
European discovery, which are wholly en- 
®^ged in the traffic in slaves. 
In a journey with a caravan it is essentially 
*^®cessary to carry a considerable quantity of 
^^ter. Sometimes a number of the camels 
^ar nothing but water-skins ; but more com- 
ll^ouly each camel carries one skin in addition to 
Is Ordinary load. That animal himself often 
three or four days without water, 
A*nkit)g twenty-five or even fifty quarts when 
has an opportunity : nay, the best camels 
transport will, we are told, endure a thirst 
? ten or twelve days, though many of them 
'^'leed perish under such a prolonged priva- 
I. K 
