180 



Nos. 1 & 2, by Mr. James Ferguson, Astronomer to the American Commis- 

 sion for determining the Northern Boundary. Dollond, 2£ feet, 

 power 00. Latitude 47° 58' 34"; long. 5/t 59m 58s.0 West of Green- 

 wich. 



Nos. 3—5, by Mr. Nicollet, at St. Mary's College, Baltimore. Lat. 39° 17' 

 55" ; long. 5/i 6m 30s. Dollond, p. 100. Nos. 4 & 5, very correct. 

 Time recorded by the Rev. Mr. A. Verot, Professor of Mathematics 

 and Natural Philosophy, in St. Mary's College. 



Nos. 6 — 11, good observations. No. 7, with power 75; No. 8, power 100; 

 Nos. 9 & 10, power 30. Time noted by Professor Ducatel; No. 11, 

 power 100. 



Nos. 17— 19, by Mr. Nicollet, at Milledgeville State House— Senate Hall. 

 Lat. 33° 4' 30" ; long. 5/t 33m 20s. The telescope was procured by 

 Mr. Nicollet of Dr. Milton Antony. Mr. Nicollet was assisted by 

 Drs. Dugas and Ford, of the Medical College of Augusta. 



Nos. 24 & 25, time by chron. Therm. 55°, 



7A 5m 9s, by obs. sun's centre alt. 25° 42' 32."7. 

 8 39 39 43 52 35.1. 



Correction of index error additive 15" to sun's alt. 



No. 26, by Mr. Nicollet, at the " Red Pipe Stone Quarry," on the " Coteau 

 des Prairies," Sioux Indian Country, Iowa Territory. Latitude 44° 

 0' 52"; long. 6h 25m 17s; assisted by Lieut. Charles Tremont, of the 

 U. S. Topographical Engineers. 



No. 32, by Mr. Nicollet, power 100, Dollond, clear sky, on the east shore of 

 Ti Tanka Taminan Lake, Lahontan River, Sioux Country, Iowa 

 Territory. Lat. 44° 16' 41" ; long. Qh 13m 23.s0. 



Nos. 33 & 34, by Dr. Goebel, at his residence near Newport, Franklin Coun- 

 ty, Missouri, power 40. Lat. 38° 33' 58" ; long. 6h 4m 28 s6. 



No. 35, by Mr. Nicollet, at his encampment on the " Coteau du Missouri," 

 Tanktonan Indian Country. Lat. 44° 51' 11" ; long. 6h 36m 18s. 



No. 36, by Mr. Nicollet, at the garden of the Cathedral, St. Louis, Missouri. 

 Lat. 38° 37' 28" ; long. 6h \m 0.s7. 



Prof. Bache read a communication from Lieut. J. M. Gilliss, 

 U. S. N., director of the Magnetic Observatory at Washington, 

 containing a description of the Observatory and of the declina- 

 tion instrument, with the means of the observations for 1840, 

 at the different magnetic hours. This communication was re- 

 ferred to a Committee. 



Dr. Hare communicated orally an experiment, showing that 

 foggy air is not a conductor of electricity. 



He adverted to the well known influence of moisture in paralyzing 

 the efficacy of electrical apparatus. When the dew point is so high 

 as to deposite moisture on the walls within doors, the most powerful 

 machines were found incompetent to generate electrical excitement. 



Dr. J. K. Mitchell having expressed the opinion, founded on some 



