I /I .'ba. 



ERRATA. 



Page 82, line 22, /or vibrate, reati oscillate. 



84, 4, /or parallelopedal, read parallopiped. 



85, 29,/or quantity, read quality. 



88, ^-tfor parallelium, read parallelism. 



— 21^ for harp-unisons, read harp, unisons. 



89, 7, /w repulsing, read repelling. 



90, 24, /or place, read plane. 



95, 6, for Baden Bowell, MA. read Baden Powell, MA. 



215, 14, from bottom, for 100 feet, read 1000 feet. 



218, 1 4, for Dex, read Dax. 



232, 15, /or New England, read Connecticut, 



299, 10, for altematis, read altemis. 

 37 1 , 6, for mean of result, read mean of his result. 



— 24, for potash, read alkali. 



The notice respecting the Correctness of the Greenwich Observa- 

 tions inserted inp, 397, and signed X, should have had the signa- 

 ture of " James South, BJackman-streetJ' 



