RAIN-FALL. 307 



June 27, a shower in the afternoon. 



June 28 and 29, no rain where we were camped. 



June 30, rained steadily all day, preventing any work being done. 



July 1, two showers during the day. 



July 2, 3, did not rain. 



July 4, rained hard all day. 



July 5, rained hard for half an hour in the afternoon. 



July 6, showers all around on the Hills, but did not rain where we were. 



July 7, 8, no rain. 



July 9, 10, 11, 12, 13, 14, 15, one or more showers each day, usually 

 after 2 p. m. 



From the above it will seem that it rained fifteen days out of twenty- 

 two. Eeferring to the published reports of the expedition to the Black Hills 

 under command of Gen. G. A. Custer, in 1874, I find that Colonel Ludlow 

 mentions this fact of the frequent occurrence of showers in the afternoon, 

 under date of July 27, while encamped on the head of Castle Creek, a 

 branch of Rapid Creek. 



This portion of the Black Hills never suffers from drought. No arid places are 

 seen except on the summits of the limestone ledges. Springs are numerous, and very 

 cold and pure. The soil is everywhere moist, and vegetation marvelously luxuriant 

 and fresh. The warm currents of air from the plains condense as they ascend the 

 slope of the hills, and robbed of their moisture in fog, rain, and heavy dews, which 

 occur nightly. The clouds almost invariably formed in the afternoon, and interfered 

 greatly with astronomical observations. (Report of a reconnaissance of the Black 

 Hills of Dakota, made in the summer of 1874, by Williain Ludlow, captain of Engineers, 

 &c, page 13.) 



Gen. G. A. Custer and Major Forsyth also mention, in their reports of 

 the expedition, the refreshing showers of rain which were frequently 

 encountered, and also the thick fogs, prolonged rains, and severe thunder- 

 storms experienced while in the Hills. That this remarkable rain-fall, 

 which was observed throughout the Black Hills during the progress of the 

 exploration, was not the exhibition of a peculiarly wet season, I can only 

 judge from the evidence given above by previous explorers during the 

 preceding year and by such observations as I was enabled to make on the 

 growth of plants and trees. In many places I noticed plants whose habits 

 of growth I was well acquainted with, which require a considerable and 



