DESERTS OF THE UNITED STATES AND MEXICO 



709 



inches in height, eventually destined to 

 become a giant cactus. The seedlings 

 of all the cacti form a favorite food of a 

 large number of small animals, being 

 juicy reservoirs of water, and containing 

 enough other material to lead to their 

 destruction before sufficient armament 

 has been formed for their protection. 



The seeds of the winter annuals of 

 the Desert of Tucson show amazing en- 

 durance. Seeds are ripened and thrown 

 on the ground in March and April. The 

 surface layers of the soil reach a tem- 

 perature of over ioo° F. during the 

 summer months. The summer rains 

 come and soak both the soil and seeds, 

 but still no activity is shown, and the ex- 

 perimentalist who attempts to use these 

 plants during the summer will find that 

 he might as well have sown so many 

 pebbles in his pans. 



PORTIONS OF the: DESERT HAVE BECOME 

 HABITABLE 



Formerly the desert was held to be 

 an uninhabitable place, but by the aid of 

 the devices of modern civilization the 

 requirements of life, comfort, and luxury 

 may be transported to the most remote 

 deserts, and large populations may carry 

 on pursuits, such as mining, uncon- 

 nected with the climate, regardless of 

 aridity. One of the most important de- 

 velopments of modern agriculture is 

 that of dry farming, in which forms of 

 economic plants are sought which will 

 produce crops under arid conditions, and 

 constant and assiduous attention is being 

 given to the development of cultural 

 methods which will facilitate the growth 

 of plants in deserts and conserve the soil 

 moisture by checking evaporation. These 

 and other individual adaptations of the 

 human animal are of extreme interest, 

 particularly when considered by the 

 archeologist engaged in the study of the 

 ancient civilization of desert peoples.* 



One of the most difficult problems to 

 solve is that of transportation in the 



*C. S. Scofield : Dry Farming in the Great 

 Basin. Bulletin No. 103, Bureau of Plant In- 

 dustry, U. S. Department of Agriculture, Wash- 

 ington, 1907. 



desert, and there are extensive areas in 

 American deserts that have not yet been 

 systematically explored by reason of 

 this condition. 



The camel is perhaps the most exten- 

 sively used of any means of transporta- 

 tion, and as such he has played an im- 

 portant part in the history of the hu- 

 man race in the arid regions of Asia and 

 Africa. This animal has also come to 

 be of great usefulness in Australia, 

 where it was introduced in 1846, and a 

 later importation of these animals, 

 brought in i860, accompanied the Burke 

 and Wills Expedition across the conti- 

 nent. 



In this same period efforts were made 

 to make use of the camel in American 

 deserts, and although the conditions 

 were undoubtedly and still seem quite as 

 favorable, the movement was a failure 

 by reason of prejudice and of the or- 

 ganization of transport of burros, horses, 

 and mules, already in a high state of 

 specialization in this region. The ex- 

 tension of railways to tap mining regions 

 and the usefulness of the modern motor 

 car, as proved in the deserts of Nevada, 

 now make any further consideration of 

 the camel unnecessary along main lines 

 of travel, while the solitary traveler or 

 the small party following personal routes 

 have available animals and supplies, so 

 that the most economical outfit is that of 

 horses, mules, and burros. A camel is 

 reputed to be able to carry a load of 600 

 pounds with ease, but the same amount 

 might be taken by three or four burros 

 at a cost of original investment and 

 maintenance only a fraction of that of 

 the camel-train. 



It is to be said, however, that a small 

 efficient camel-train would make possible 

 the scientific exploration of the deserts 

 of western Sonora and of the region 

 traversed by the Camino del Diablo with 

 some certainty of success. 



HOW LONG CAN MAN LIVE WITHOUT 

 WATER ? 



A com prehension of the part that wa- 

 ter plays in existence and travel in the 

 desert is to be gained only by experience. 



