252 AGRICULTURAL INDICATORS. 



East of this, only the most intense droughts will be noted as such, and the 



minimum crop production is apt to occur in years of excessive rainfall. In 



the Southwest, where the rainfall is always low, the economic effects of drought 



may occur in almost any year when the distribution or timeliness of the rain 



is at fault. The existence of a chmatic cycle coinciding with the sun-spot 



t cycle, and consisting of a dry and a wet j)hase which falls respectively at the 



\ sun-spot maximum and mininium, appears to be estabUshed beyond a doubt 



j by the work of Douglass, Huntington, and Kapteyn, as well as by the study of 



j vegetation. Much more work is required to explain certain apparent excep- 



i tions and contradictions in widely divergent climates, but none of these seem 



to invahdate the general principle. 



Significance of the sun-spot cycle. The establishment of a cycle of rela- 

 tively dry and wet periods with a usual length of 10 to 12 years is of para- 

 mount importance to the practice of agriculture, forestry, and grazing in the 

 West. Since rainfall is the Umiting factor over most of the region, a knowl- 

 edge of what can be expected in the way of variation in rainfall and changes 

 of climate will be of the greatest help. The most serious handicap to the 

 proper agricultural development of the West lies in the almost universal 

 misconception of climate and the nature of its changes. Much of this 

 arises from the mistake of the earher geographers in regarding the Missouri 

 Valley as a part of the "Great American Desert." The rapid development 

 of this region was sufficient proof that it had never been desert, but the per- 

 sistence of the old idea could be reconciled with the facts only by the assump- 

 tion that the rainfall had greatly increased as a result of cultivation. This 

 \ impression that the rainfall was increasing was further strengthened by the 

 luxuriant development of the tall-grasses as a consequence of the disappear- 

 i ance of the buffalo. This mistaken idea still persists over much of the West, 

 i where a marked and permanent increase in rainfall is confidently expected to 

 follow settlement. This error has further serious consequences in that it leads 

 to each drought period beingj-egarded as the last, and consequently prevents 

 the adoption of systems of settlement and management which will reckon 

 with drought periods as certain to recur. Even where experience made it 

 clear that droughts still occurred, the prejudice in favor of a changing cli- 

 mate, together with the general optimism and inertia of the pioneer, pre- 

 vented the recognition of the patent fact. Moreover, during the disastrous 

 drought of 1916-18, stockmen were often found who admitted that drought 

 had occurred before and probably would again, but stated that this fact 

 would be readily forgotten when the rains came. 



The meteorologists have proved repeatedly, from the weather records, that 

 there has been no progressive change in the climate of the West during the 

 settlement of the latter. This has been conclusively shown by Swezey and 

 Loveland (1896: 137) for Nebraska, the central position of which makes it 

 typically representative of the climate and vegetation of the grassland climax: 



"If we examine the precipitation for the series of years from 1849 to 1895 

 inclusive given in Appendix II, we shall find that, although the rainfall of the 

 past few years has been less than that of the earlier years of the series, so far 

 as we can judge from the rather meager records of those earlier years, yet 

 there is afforded no evidence of any considerable progressive change in the 

 climate of the State, either toward wetter or drier conditions. There have 



