The camel can do yet another wonderful thing. He can tell a long way off when he is coming to a place where there is water. In the desert, after going over sand and sand for many days, a traveler sometimes finds a beautiful place called an _oasis_. It is just like a lovely little garden right in the middle of the desert, with a spring of water, and several fig trees, date trees, and other palm trees growing all around the pool. When a traveler is crossing the desert and sees nothing but sand for several days, it sometimes happens that his camel suddenly stops, stands quite still for a minute, raises his head, and sniffs the air. Then he turns a little to the right or to the left, and begins to run straight that way. His master may look ahead very hard, but he will see nothing but sand and sand, as before. But the camel, by just sniffing the air, has found out that there is an oasis within reach, though it is still too far away for him to see it. Then he runs on most gladly, and comes to the oasis in an hour, so that he and his master can rest there for some time, and drink from the pool, and eat the figs and dates growing on the trees. Of course, the camel can also eat the leaves of the trees; in fact, when he is not in the desert, but just in the ordinary country, he usually eats from the shrubs and bushes, and gets figs and dates only as a dainty, just as you sometimes have ice cream. The camel with two humps will gladly eat many more things than the camel with one hump. In fact, when he is hungry, he will eat not only any kind of vegetable, but also meat. He has even been known to chew up and eat bones, blankets, and leather! And he is perhaps the _only animal that will drink salt water_; for the country in which the Two-Humps camel lives has several lakes, the water of which is bitter and salty. So you see how useful an animal the camel is, whether he has one hump or two humps. He is so useful that people have been saying for a long time that camels should be brought into America, where there are several deserts in the western states. In fact, a strange thing has already happened. The United States Government did bring a lot of camels for use in the western states several years ago, about the time when your grandfather was a boy. But the people who can best manage such large animals as elephants and camels are the people who are born in the same countries as those animals and who understand their habits. And unluckily, when the camels were brought into America, nobody thought of bringing men also from those countries to manage the camels. So nobody seemed to know how to use these animals, and after a time they were turned loose in Arizona. The camels went into the deserts and forests there, and became quite wild, and to-day there are some of them in Arizona.