AT SANTIAGO DE CHILE. 



153 



Remarks. 



There were two sharp earthquakes at an interval of 12s. about 6/t. 12m. p. in., and their effect seems to have been to change the atmospheric con 

 dition. Planet and star are at one instant steady, and before half way across the field, blurred and jumping in a most extraordinary manner. The 

 measures, therefore , could not have been very good, even had there not been the additional difficulty of endeavoring to keep Mars on the middle wire, 

 with the tangent screw, whilst the micrometer wire was moved to bisect the star. Thus only one reading of the micrometer appears, the star being 

 that number of revolutions to the north of the planets limbs. 



a The three preceding observations are not incorporated into the means. 



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