AND CONSTRUCTION OF RAIN-FALL CHARTS OF THE UNITED STATES. 193 



CHART SHOWING THE DISTRIBUTION OF THE RAIN-FALL DURING AUTUMN. 



The curves are given for every second inch from 2 to 20. In general, the distri- 

 bution is irregular, and the areas of equal fall are much broken up. There ai-e still 

 in Louisiana 18 inches, and on the coast of Washington Territory 20 inches of rain. 

 This latter rain area, which had disappeared during summer, has now reappeared to 

 attain its maximum growth during the coming winter. In Florida the broken 

 remains of the summer rains are still persistent, but destined to disappear during the 

 winter. A notable feature in the autumn rains is the detached areas of comparatively 

 great rain-fall in the vicinity of the great lakes, rising to 12 and 14 inches; and 

 another characteristic fact is the development of a rain belt near the Atlantic shore, 

 between Florida and Maine, showing falls between 10 and 14 inches. 



If w'Ti glance once more on the chart of the yearly average distribution we notice 

 that many of the characteristic features shown by the chart for each season have their 

 traces imj)ressed upon it ; thus, we recognize the detached patches of 44 inches of 

 rain scattered, on an arc between Iowa and Pennsylvania as formed by the breaking 

 up of the vapor current, on its way north, through the influence of the westerly 

 winds. Over the winter part of the elevated area of the western section of the 

 United States the rain charts are still very imperfect for want of material, especially 

 during the winter season ; and, considering the diversified configuration of the country 

 and. the great variations in the rain and snow fall as depending on height, very much 

 labor remains to be expended before we can gain any more satisfactory knowledge 

 of the facts. 



