71 



August 7 and August 22, we had much overcast and misty weather 

 nearly all the time, and on seven of tlie days rain fell in small 

 quantities. 



From August 25 to September 12 we were on the road along the 

 Platte river between Fort Kearney and Fort Laramie ; during this 

 time we had two heavy thunder storms, attended with a large fall 

 of rain. While at Fort Laramie, we had heavy frost about the 25th 

 of September. Fort Laramie has an elevation of 4,200 feet. 



From September 29 to October 19 we were on the road to Fort 

 Pierre. The weather at times was very cold, and snow fell to the 

 depth of four inches on the night of the 3d of October; for several 

 days in the first part of this month the thermometer stood, at day- 

 break, at 29°. On the 20th and 2l8t of October we had a violent 

 storm of rain^ sleet, and snow, with high winds, which covered 

 everything with ice. We were quite surprised, on reaching the 

 neighborhood of Fort Pierre, to find the grass green and abundant, 

 for it was such a contrast to its appearance in August, when every- 

 thing seemed to have perished for want of rain. Much snow fell 

 here during the winter, and in the spring there were heavy showers 

 of rain, so that a more beautiful prairie country could not be found 

 than this, as it appeared in May and June, 1856. At the same time 

 the previous year the grasses scarce gave an indication of life. 



We left Fort Pierre on the 28th of June, 1856, and reached Fort 

 Union on the 10th of July; on the passage the weather was compara- 

 tively clear, with light winds. Up to this time no rain had fallen 

 there, and in many places there was a great scarcity of grass. On 

 the 15th a heavy storm of rain and wind commenced at 9 p. m., and 

 continued till 10 p. m. on the 17th. The wind for several days 

 previous had been light, and came from the north. On the 15th, at 

 2 p. m., the thermometer was at 90°, the barometer (reduced to 32°) 

 reading 27.827. At 9 a. m., on the 16th, the barometer read 

 27.735; thermometer 58°. The wind blew with great violence from 

 the north all day on the 16th, so that it was with great difficulty 

 we kept our tents standing ; and a portion of the enclosure of the 

 American Fur Company's fort was blown down. This storm was 

 not accompanied by thunder and lightning. On the 17th the 

 weather was again clear ; wind light from the northeast ; ther- 

 mometer, at 2 p. m.^ 67°; barometer, 28.179. Fort Union has an 

 elevation of 1,900 feet above the sea. 



While at Fort Union and in the neighborhood we had after this 

 abundance of rain, so that the whole landscape in August and Sep- 

 tember wore a beautiful green, and grass was plenty in places where, 

 in July, there was not a blade of it. The highest temperature we 

 experienced here was on the 20th of July, the thermometer, at 2 p. 

 m., reading 93°. The earliest frost ever recorded to have occurred 

 here was in the month of August of 1855. 



We left Fort Union the first of September and reached Fort Pierre 

 on the fifth of October. We were again struck with the variable 

 nature of the climate on finding that but little rain had fallen here 

 during our absence and the grass had all dried up, though at this 

 place the same period of the previous year it was everywhere green. 



