The travois was a transportation device used by the nomadic Plains
Indians.  The larger ones were made from two tipi poles tied together at
one end and fastened over a horse's shoulders, with the other ends left to
drag behind.  A platform was made in the rear from short crosspoles lashed 
and covered with buffalo rawhide, often the same skins used for the 
tipi.  In this way the whole tipi could be converted into a cart and used 
to carry goods, food, and sometimes sick or wounded tribe members.  
Smaller ones hitched to dogs, like that pictured above, were made from 
two flexible wood poles and a litter constructed of willow and leather.  
These were often used to transport children or the elderly.  The scene 
shows a family of Kansas Indians making their annual winter migration.