X CONTENTS. 



ARTICLE V. 



Observations to determine the Magnetic Intensity at several Places in the United States, 

 with some additional Observations of the Magnetic Dip. By Elias Loomis, Professor of 

 Mathematics and Natural Philosophy in Western Reserve College. - - - - 61 



ARTICLE VI. 



On the Perchlorate of the Oxide of Ethule or Perchloric Ether. By Clark Hare and 



Martin H. Boye. 73 



ARTICLE VII. 

 Observations on the Storm of December 15, 1839. By William C. Redfield, A. M. - 77 



ARTICLE VIII. 



On the Perturbations of Meteors approaching near the Earth. By Benjamin Pierce, 

 A. A., Hollis Professor of Mathematics and Natural Philosophy in Harvard University; 

 in a Letter to S. C. Walker, Esq. 83 



ARTICLE IX. 



Researches concerning the Periodical Meteors of August and November. By Sears C. 



Walker, A. P. S. 87 



ARTICLE X. 



Astronomical Observations made at Hudson Observatory, Latitude 41° 14' 40" North, and 

 Longitude 5/i. 2bm. 45s. West. By Elias Loomis, Professor of Mathematics and Natural 

 Philosophy in Western Reserve College. - 141 



ARTICLE XI. 



Expansion of F {x + h). By Pilie Powers, of the University of Virginia. - - - 155 



ARTICLE XH. 

 Description of New Fresh Water and Land Shells. By Isaac Lea. - - - - 163 



