The Apaches were dreaded alike by the agricultural Indians and the early Spanish. Issuing from their mountain fastnesses the Apaches would raid the unprotected villages and missions, and then retreat as quickly as they came. For many years after the American occupation prospectors had to be constantly on their guard, and many are the tragedies that have marked this remote corner of our country. THE LIFE OF THE DESERT During the blinding glare of summer the deserts of southwestern Arizona and the adjoining portions of California are forbidding in the extreme. Day after day the pitiless sun pours its heat upon the vast stretches of barren mountain and plain, until the rocks are baked brown and it seems as if every particle of life must have left the seared and motionless plants. Month after month passes without rain. Now and then light clouds float into sight, and occasionally rain can be seen falling from them, but they are so high that the drops all disappear in the dry and thirsty air long before they can reach the ground. Cloud-bursts may take place about the peaks of some of the higher mountains, but they have very little effect upon the life out on the plains. Animals and plants brought to this region from a moister climate must drink continually to make up for the rapid evaporation of moisture from their bodies; a day without water may result in death. And yet the living things that have homes in the desert can resist the dry air for many months without a renewal of their moisture. There are areas where the average rainfall is less than three inches, and sometimes two years may pass without a drop of rain. It will certainly be worth our while to find out something about these desert plants and the way in which Nature enables them to get along with so little water. Go where we will, from the moist heat of the tropics or the dry heat of the deserts to the icy north, we find that everywhere the plants and animals are suited to the climate of the particular place in which they live. Therefore we might conclude that they thrive better in those places than they would anywhere else, but that is not always true. A struggle is going on continually among plants for a footing in the soil and for a share of the sunshine. The weaker plants are generally killed, while those hardy enough to survive have to adapt themselves to new conditions of life, becoming stunted and deformed upon barren slopes; but they have plenty of room there because fewer plants are striving for the same place.