506 



Mr ROTHMAN'S OBSERVATIONS OF HALLEY'S COMET. 



These differences do not depend entirely, though of course they 

 do partly, on errors of observation. They are, in several instances, 

 largest on the places that are best determined. This is the case in 

 a remarkable manner with the declination of the 19th October. This 

 is the best determined place of the whole series. It rests upon five 

 observations in good accordance with each other ; and the star of com- 

 parison is in Mr Pond's last Catalogue, and consequently is known with 

 great accuracy. 



R. W. ROTHMAN. 



London, Nov. 23, 1837. 



