BAROMETRICAL AND METEOROLOGICAL OBSERVATIONS. 187 



C— Table of daily oscillations of the force of vapor, in inches (Eii(ilish), of the mercurial column. 



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loi,. in »;--■-, 



T).— Table of <l ■ relative hu nullify. Satn 





No. I C and D was deduced from 11 days' observations at Fort Kearney, Ne- 

 braska, from June 19 to 30, 1858, at an elevation of 2,200 feet above the level of 

 the sea. 



The mean temperature was 77°.5 Fahrenheit. The mean force of vapor was 0.628 

 inch; the relative humidity, 68.4. and the mean weight of vapor in one cubic foot 

 of air, 6.75 grains troy. (See Table E.) No. I C and D corresponds to No. I B, 

 and very nearly also to No. 11 A, which may be considered as forming together one 

 set. It rained on five occasions altogether during 28 hours, bur the aggregate quantity 

 of rain was only 1.40 inches. Dew was observed on 3 mornings. Of the 12 nights 

 which this mean includes sheet-lightning was observed on 7, which on one occasion 

 terminated in a thunder-storm, of which there were two. The cloudiness of the sky 

 between the hours of 6 a. m. and 10 p. m. averaged 3.66, the whole sky being 10, and, 

 including the hours of the night by interpolation, 3.35. The clouds were mostly 

 cirro-cumuli, or cirro-stratus, except when it rained. The 190 hourly observations of 

 the wind during that time, between 5 a, m. and 10 p. m., give the following results, 

 the strength being expressed by the numbers from to 10: 



