326 OBSERVATIONS OF THE MAGNETIC DIP 



RemarJcs.'—AYediiher cloudy, light north-east wind. The temperature 

 during the observations from 51° to 56°. 



XXIII. Magnetic Dip at St. Louis, Missouri. Latitude 38° 37' 28" N.; 

 Longitude 90° 15' 10" ?F. 



Place of observation on the east side of the Mississippi River, in a grove 

 opposite Bloody Island, near Illinois Town, about one mile east of St. Louis. 



Date. Hour. Needle No. 1. Needle No. 2. 



1841, Oct. 6, 1|— 31, P. M. Observed dip, Poles direct, 69° 31'.05 69° 16'.98 



" " " Poles reversed, 24 .98 34 .08 



Mean dip, 69 28 .01 69 25 .33 



Mean dip of both needles, 69 26.67 



Remarks: — Sky clear, south-east wind, brisk at intervals. The temperature 

 during the observations from 72° to 76°. 



XXIV. Magnetic Dip at St. Louis, Missouri. 

 Place of observation in Mr. Henry Chouteau's orchard, on the west shore of 

 Chouteau's pond, about half a mile west of the Mississippi River, or one and a 

 half mile west of the preceding station. 



Date. Hour. Needle No. 1 . Needle No. 2. 



1841, Oct. 11, 2^—4^, P. M. Observed dip, Poles direct, 69^ 22'.90 69° 12'.62 



" " " Poles reversed, 29 .80 43 .18 



Mean dip, 69 26 .35 69 27 .90 



Mean dip of both needles, 69 27.12 



Remarks: — Weather cloudy and calm. The temperature during the obser- 

 vations, 67° to 65°. 



XXV. Magnetic Dip at Baltimore, Md. 

 Place of observation the botanical garden of St. Mary's college. 



Date. Hour. Needle No. 1. Needle No. 2. 



1841, Nov. 15, 11 A. M.— U P. M. Observed dip, Poles direct, 71° 46'.90 71° 49'.32 



■• " Poles reversed, 34.12 33.07 



Mean dip, 71 40.51 71 41.19 



Mean dip of both needles, 71 40.85 



Remarks. — Weather cloudy, sun shining at intervals, high south-west wind, 

 not interfering with the observations as they were made in the Magnetic 

 Pavilion recently constructed. (See the remarks No. X., above.) 



This observation, which gives nearly the same result as that found at the 

 same place on the 20th of August, before leaving Baltimore, shows that the 

 needles have suffered no material changes during my magnetic tour. 



