SMITHSONIAN CONTRIBUTIONS TO KNOWLEDGE. 



METEOROLOGICAL OBSERVATIONS 



PROVIDENCE, R.I. 



EXTENDING OVER A PERIOD OF TWENTY-EKJIIT YEARS AND A HALF, 

 FROM DECEMBER IHol TO MAY IStil). 



BY 



ALEXIS CASWELL, 



PnoFESSOR OF SATURAL PHILOSOPUV AND ASTUONOMY IS BROWN L'NlVERalTy, PROVIDENCB, RUOUE ISLAND. 



[ACCEPTED FOR PPBLICATION, ADGPST, 1859.] 



