OF THE ATMOSPHERIC TEMPERATURE. 



313 



The second type-curve is made up from the stations: Fort Snelling, Minn., 

 Muscatine, Iowa, St. Louis, Mo., Fort Leavenworth, Kan., and Fort Gibson-, Indian 

 Ter. These series have 19 years in common (1839 to 1857 inckisive), for each of 

 which the means from the five values were set down, the observed annual tempera- 

 tures for years before and after were first referred to the same mean series by the 

 reductions +7°.9, +4°.7, — 3°.2, — 0°.8, and — 8°.6 to the stations respectively 

 (these numbers were deduced from comparisons of each series with every other). 

 We have the foUowine- tables : — 



Table of consolidated mean annual temperatures at Fort Snelling, Ifuscatine, St. Loiii 

 Leavenworth, and Fort Gibson. 



Fort 









I 



2 



3 



4 



5 



6 



7 



8 



9 



1820 



S°-9 



50.8 



SI. 6 



Si-3 



50-7 



S5-0 



52-3 



54-6 



54-6 



52-4 



1830 



55-6 



48.9 



52-7 



S4-I 



S3-I 



50.2 



49-7 



51-7 



49.6 



53-6 



1840 



52.0 



511 



52-1 



49.0 



52.1 



53-2 



54-1 



49.6 



50.8 



50-7 



1850 



Si-7 



52-9 



51.2 



51.8 



54-2 



52.0 



49-5 



49.9 



53-1 



SI-7 



i860 



53-7 



53-2 



Si-9 



Si-7 



51-7 



52.8 



51.0 



Si-3 



Si-4 



50.6 



1870 



53-6 





























General mea 



1. SI-9S- 











From the above table we derive the followin<^ successive means of the 4th order: — 









I 



2 



3 



4 



s 



6 



7 



8 



9 



1820 



.._ 



(SI- 1) 



Si-3 



Si-4 



52.0 



53-0 



S3-6 



S3-9 



S3-9 



53-6 



1830 



52-9 



52-1 



S2-3 



S2-9 



52-3 



51-1 



5°-S 



S°-7 



SI-4 



52-1 



1840 



52-1 



5t.6 



Si-i 



51.0 



51.8 



52.6 



52.4 



Si-3 



50.8 



Si.o 



1850 



51.6 



Si-9 



52.1 



S2-3 



S2-S 



51.8 



So-7 



50.8 



SI. 8 



52-5 



i860 



52.8 



52-7 



52.2 



Si-9 



51-9 



51-9 



Si-5 



SI-3 



51-3 



(5 1. 6) 



1870 























Table of differences from the mean 52°.o. 









I 



2 



3 



4 



5 



6 



7 



8 



9 



1820 







(-0-9) 



—0.7 



_o.6 



0.0 



+ 1.0 



+ 1.6 



+ 1-9 



+ 1-9 



+ 1.6 



1830 



4-0.9 



+0.1 



+0.3 



H-o-9 



+0-3 



—0.9 



—1-5 



—1-3 



— 0.6 



+0.1 



1840 



+0.1 



—0.4 



—0-9 



■ — i.o 



■ — 0.2 



+0.6 



4-0.4 



—0.7 



— 1.2 



— 1.0 



1850 



— 0.4 



— 0. 1 



+0.1 



+0-3 



+0-S 



■ — 0.2 



—1-3 



— 1.2 



— 0.2 



+°-S 



i860 



+0.8 



+0-7 



-fo.2 



— 0.1 



— 0.1 



— 0.1 



— o-S 



—0-7 



—0.7 



(-0.4) 



1870 























[This table can be used to obtain normal temperatures at places in the Mississippi valley, as 

 explained above.] 



40 June, 1S75. 



